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Background and Aims: The intercropping has great advantages in production gain, resources use and soil quality improvement. However, the effects of perennial forage legumes intercropped with annual grain crop on soil alkali-salinity was not well revealed. This study aimed to propose a spring wheat (Triticum aestivum L.)/alfalfa (Medicago sativa L.) intercropping and reveal whether this cropping system could ameliorate soil salinity. Methods: A two-year field experiment was conducted under 3 cropping systems at 3 irrigation amounts in the inland arid area of northwestern China. The cropping systems were sole spring wheat cropping (W), 12 rows spring wheat/4 rows alfalfa intercropping (W12A4) and 8 rows spring wheat/4 rows alfalfa intercropping (W8A4), and irrigation amounts included 450 (full irrigation amount, If), 360 (moderate irrigation amount, Im) and 180 mm (low irrigation amount, Il). Results: The intercropping system, especially W8A4, could more decrease soil salinity, pH and topsoil bulk density, and increase soil water content, topsoil porosity, and Ca2+ and Mg2+ contents, compared to W. Soil electrical conductivity was positively correlated with topsoil bulk density and negatively correlated with topsoil porosity, which were enhanced by intercropping and irrigation. There was weak correlation between soil electrical conductivity and soil water content. W12A4 and W8A4 led to reduction in contents of Na+, K+, Cl−, and SO42−, while Ca2+ and Mg2+ accumulated in the soil. Conclusion: Intercropped alfalfa and spring wheat could reduce soil salinity, improve soil structure and ions balance. It was recommended that W8A4 with 360 mm irrigation could be extensively used in the arid area of northwestern China, gaining grain and forage production, and helping reduce salt accumulation. [ABSTRACT FROM AUTHOR]

Cultivated grasslands are an important part of grassland ecosystems and have been proven to be major carbon sinks, then playing an important role in the global carbon balance. The effect of cultivated grassland type (Medicago sativa, Triticum aestivum, Secale cereale, and Vicia villosa grasslands) on carbon flux (including net ecosystem CO2 exchange (NEE), ecosystem respiration (ER), and gross ecosystem productivity (GEP)) downstream of the Yellow River was studied via the static chamber technique and a portable photosynthetic system. Bare land was used as a control. The results showed that the four cultivated grassland types were mainly carbon sinks, and bare land was a carbon source. The cultivated grassland types significantly affected carbon flux. The average NEE and GEP of the grassland types were in the following order from high to low: Medicago sativa, Secale cereale, Triticum aestivum, and Vicia villosa grassland. Stepwise regression analysis showed that among all measured environmental factors, soil pH, soil bulk density (BD), soil organic carbon (SOC), and soil microbial carbon (MBC) were the main factors affecting CO2 flux. The combined influence of soil BD, SOC, and pH accounted for 77.6% of the variations in NEE, while soil BD, SOC, and MBC collectively explained 79.8% of changes in ER and 72.9% of the changes in GEP. This finding indicates that Medicago sativa grassland is a cultivated grassland with a high carbon sink level. The changes in carbon flux were dominated by the effects of soil physicochemical properties. [ABSTRACT FROM AUTHOR]

This research evaluated several methods to help reduce pivot ruts or wheel tracks on pivots. On-farm trials were established at nine site-years with corn (Zea mays L.), alfalfa (Medicago sativa L.) and wheat (Triticum aestivum L.) during 2020–2022 in Utah and Idaho. The eight-boom design (i.e., Advantage booms) had mostly positive crop responses but did not reduce wheel track depth. The part circle (PC) method provided much shallower tracks at one site, but it also lowered crop yield. At other sites there were minimal effects to yield and quality with the PC method, but the early-season, shallow wheel tracks did not usually last through the heaviest time of irrigating. The low energy precision application (LEPA) method was the most reliable method for maintaining crop yield and quality, while improving wheel tracks. The single boom method often maintained crop quality, but it also often reduced yield, and did not improve wheel tracks compared with the nontreated controls. The polyacrylamide had few effects on crop yield and quality, or wheel track depth. There was no approach in the study that maintained yield and reduced pivot track depth compared with no treatment in every scenario, but the LEPA method displayed the greatest potential for uniformly irrigating the area near the wheel track to maintain crop yield and quality, while minimizing water entering the track, to help reduce burdensome pivot ruts. Thus, LEPA may be one of the most effective sprinkler modifications for reducing pivot tracks and adequately irrigating the area around the track. This research evaluated how several sprinkler modifications and a soil conditioner help reduce pivot ruts or wheel tracks on pivot irrigation systems. On-farm research trials were established at six fields with corn, alfalfa, and wheat during 2020–2022 in Utah and Idaho. The eight-boom sprinkler modification had mostly positive crop responses but did not reduce wheel track depth. The part circle (PC) sprinkler method sometimes reduced wheel rut depth but came at the expense of lost crop production. The low energy precision application (LEPA) sprinkler method was the most reliable method for maintaining crop yield and quality, while improving wheel tracks. The single boom method often reduced yield and did not improve wheel tracks compared with the nontreated tracks. The polyacrylamide soil conditioner had few effects on crop yield and quality, or wheel track depth. There was no approach in the study that maintained yield and reduced pivot track depth compared with no treatment in every scenario, but the LEPA method displayed the greatest potential for uniformly irrigating the area near the wheel track and maintaining crop yield and quality. Thus, LEPA may be one of the most effective tools for reducing pivot tracks and adequately irrigating the area around the track. [ABSTRACT FROM AUTHOR]

Soil organic carbon was measured after surface application of equal C amounts from various C sources to fallow soil or a winter wheat crop for five consecutive years. Municipal biosolid produced the largest gain, followed by manure and alfalfa (Medicago sativa L.) foliage. Wheat (Triticum aestivum L.) straw, sucrose, and wood sawdust were not different than no addition. These effects were additive to and independent from the effect of fallow soil versus cropped soil. Soil cropped to winter wheat increased in C comparable to the biosolid application or to plots planted to perennial grass. Measurements 4, 6, and 12 years after a return to normal farming practices produced no change in relative or quantitative differences. These results illuminate the durability of above‐ and below‐ground contributions to soil C. Core Ideas: Increased soil organic carbon (SOC) produced by crop roots or amendments is still present 12 years later.The effect of wheat straw and sucrose on SOC was not significant, but biosolids, manure, and alfalfa increased SOC.Five years of wheat or perennial grass produced a substantial gain in SOC compared to fallow. [ABSTRACT FROM AUTHOR]

We evaluated the impact of weather and fertilization treatments (Control, PK, NPK1, NPK2, and NPK3) on winter wheat grain yields in a long-term trial in Ivanovice, Czech Republic, established in 1956. A total of 15 seasons were evaluated. The mean, maximal, and minimal temperatures in Ivanovice have been significantly increasing since 1961, with annual increases of 0.04 °C, 0.03 °C, and 0.05 °C, respectively. Precipitation has been decreasing annually by −0.54 mm (trend is insignificant). Four significant correlations between weather and grain yield were recorded. There were positive correlations between mean (r = 0.7) and minimal (r = 0.5) temperatures in November and negative correlations between mean temperatures in May (r = −0.6) and June (r = −0.6). The combination of naturally fertile chernozem soil and a beneficial preceding crop (alfalfa) enables sustainable cultivation of wheat, even without mineral fertilizers. The application of mineral nitrogen (N) significantly increases wheat grain yield and yield stability. Without mineral N or with high doses of mineral N, yield stability decreases. According to two response models (quadratic and quadratic-plateau), a reasonable dose of fertilizer is 107 kg ha−1 N for modern wheat varieties, corresponding to a yield of 8.1 t ha−1. [ABSTRACT FROM AUTHOR]

The use of acid soil‐tolerant annual legume pasture species and liming to raise soil pH can have legacy effects that improve subsequent wheat crop growth in acid soils. We established a two‐year experiment in a semi‐arid environment with and without historical lime application to investigate how acid soils (±lime) influence the legacy effects of annual legume pastures. We measured legume and cereal growth and yield, soil‐borne disease incidence, rhizosheath organic acid type and amount, legume biological nitrogen fixation (BNF) and soil moisture in Year 1, and soil microbial biomass carbon (MBC) and wheat yield and quality in Year 2. Minor differences in soil moisture and soil‐borne diseases occurred between cereals and legumes, and the poor BNF contribution of all pasture legumes improved in lime treatments. Pasture legumes produced more organic acids than cereals, which increased in limed treatments. Soil MBC in Year 2 was greater following legumes than cereals. Year 2 wheat grain yield increased following pasture legumes, more so in limed treatments. The contribution of organic acid exudation by annual legume pastures to microbial community legacy effects warrants further scrutiny in semi‐arid environments, particularly when acid soils limit typical rotational benefits. [ABSTRACT FROM AUTHOR]

This review describes the role of silicon (Si) in plants. Methods of silicon determination and speciation are also reported. The mechanisms of Si uptake by plants, silicon fractions in the soil, and the participation of flora and fauna in the Si cycle in terrestrial ecosystems have been overviewed. Plants of Fabaceae (especially Pisum sativum L. and Medicago sativa L.) and Poaceae (particularly Triticum aestivum L.) families with different Si accumulation capabilities were taken into consideration to describe the role of Si in the alleviation of the negative effects of biotic and abiotic stresses. The article focuses on sample preparation, which includes extraction methods and analytical techniques. The methods of isolation and the characterization of the Si-based biologically active compounds from plants have been overviewed. The antimicrobial properties and cytotoxic effects of known bioactive compounds obtained from pea, alfalfa, and wheat were also described. [ABSTRACT FROM AUTHOR]

The research aimed to study the production, consumption, and determinants of the food balance of wheat, to study the most important factors affecting wheat consumption, and to study the most important means of narrowing the wheat gap in Egypt. The results show an increase in both the area of wheat and wheat production, the price of farmed wheat in Egypt increased annually, statistically, by an amount of about 52.61 thousand faddans, 128.81 thousand tons, and 196.33 pounds per ton, respectively, the results of estimating each crop available for consumption are shown, wheat, the wheat gap, and the average per capita share increased during the study period by a statistically significant annual amount of 0.55, 0.4 thousand tons, and 1.1 kilograms per year, respectively, a statistically significant decrease was found in the annual self-sufficiency ratio, which amounted to about 0.94. The results show that an increase in the population, per capita income, and consumer price by 10% leads to an increase in the consumed quantities of wheat by about 5.9%, 1.7%, and 1.8%, respectively. It turned out that the most important means of reducing the wheat gap in Egypt is to follow a stimulating price policy for farms that works to increase the cultivated area of wheat, and to make silage from an area of 500 thousand acres of maize without cobs, it is possible to dispense with 635 thousand acres of alfalfa area, and thus lies the increase in the total output of wheat is about 1.6 million tons, which fills about 22% of the average size of the wheat gap in Egypt during the period (2000-2020), which is about 7.394 million tons. Estimating the amount of wheat lost, it was found that the average amount of loss amounted to 2.794 million tons during the period (2015-2020), with an estimated value of about 9748.796 million pounds, and that the average amount of lost wheat was produced from an area estimated at 1,085 thousand faddans, and that this the area consumed an amount of irrigation water amounting to about 1574.623 million m3, and it is clear that the average amount of wheat lost could have been sufficient to feed about 10.28 million people of Egypt's population. Based on the results, the research recommends the necessity of: Work to reduce waste by using modern technology in harvesting, transportation, storage and manufacturing. Adopting a stimulating price policy for farms that works to increase the cultivated area of wheat. Working to spread the technology of making silage from maize without cobs to preserve corn grains and reduce the area of alfalfa [ABSTRACT FROM AUTHOR]

The PLATZ family is a novel class of plant-specific zinc finger transcription factors with important roles in plant growth and development and abiotic stress responses. PLATZ members have been identified in many plants, including Oryza sativa, Zea mays, Triticum aestivum, Fagopyrum tataricum, and Arabidopsis thaliana; however, due to the complexity of the alfalfa reference genome, the members of the PLATZ gene family in alfalfa (Medicago sativa L.) have not been systematically identified and analyzed. In this study, 55 Medicago sativa PLATZ genes (MsPLATZs) were identified in the alfalfa "Xinjiangdaye" reference genome. Basic bioinformatic analysis was performed, including the characterization of sequence lengths, protein molecular weights, genomic positions, and conserved motifs. Expression analysis reveals that 7 MsPLATZs are tissue-specifically expressed, and 10 MsPLATZs are expressed in all examined tissues. The transcriptomic expression of these genes is obvious, indicating that these MsPLATZs have different functions in the growth and development of alfalfa. Based on transcriptome data analysis and real-time quantitative PCR (RT-qPCR), we identified 22, 22, and 21 MsPLATZ genes that responded to salt, cold, and drought stress, respectively, with 20 MsPLATZs responding to all three stresses. This study lays a foundation for further exploring the functions of MsPLATZs, and provides ideas for the improvement of alfalfa varieties and germplasm innovation. [ABSTRACT FROM AUTHOR]

Both from the environmental and economical perspective, reducing the use of mineral nitrogen and herbicides is one of the future challenges in cereal production. Growing winter cereals on perennial legume living mulch such as white clover (Trifolium repens L.) or lucerne (Medicago sativa L.) is one of several options to reduce the need for mineral nitrogen fertilizer and herbicides in winter cereal production. Given the importance of winter cereals in the world, adopting this technique could greatly improve the sustainability of crop production. Through competition with the crop however, the living mulch can negatively affect cereal yield. Here, we (i) review how living mulch can be introduced in the system, (ii) synthetize potential advantages and disadvantages of that system, and (iii) explore different strategies to control the competition between the crop and living mulch. The major findings are that (i) competition between cereals and mulch can lead to significant yield reductions if not controlled properly and (ii) perennial legume varieties used as living mulch so far are varieties bred for forage production. We hypothesize that a dedicated breeding program might lead to living mulch varieties with a smaller impact on cereal yield compared to forage varieties, allowing to grow cereals with reduced nitrogen and herbicide inputs. We propose the main characteristics of an ideotype for such a perennial legume variety. [ABSTRACT FROM AUTHOR]

Several studies have shown the potential of using mycorrhizal fungi in increasing the plant yield by simultaneously reducing damages caused by pathogens. Plant parasitic nematodes (PPNs) are among the most feared pathogens for crops. This study aimed to evaluate the effects of Funneliformis mosseae as a mycorrhizal fungus on the population abundance of three world widespread species of nematodes from the family Criconematidae: Mesocriconema xenoplax, Mesocriconema antipolitanum, and Criconemides informis. Pure and highly abundant populations of each species were collected from Urmia city in Northwestern Iran, after the identification morphological and morphometric characteristics. The experiments were carried out in greenhouse conditions on three different rhizospheres of alfalfa, sugar beet, and wheat. After five months, the final population of nematodes and fungus, and the root surface on host plants inoculated and non-inoculated with the fungus F. mosseae, were evaluated. The results showed that the population of nematodes was increased in the presence of the fungus. It could be assumed that the extension of the host surface level of roots by the fungus resulted in more feeding sites for nematode activity and, consequently, higher population densities. In this study, the fungus did not seem to play a suitable role in controlling ectoparasitic nematode growth. However, since there are still many open questions about mycorrhizal fungi's role in agriculture, more research should be conducted. [ABSTRACT FROM AUTHOR]

Cropping systems are one of the most important living components affecting the surface soil spatial variability. Composite disturbed and undisturbed soils were collected (intersections of the grid system, 50 x 50 m) at 0-20 and 20-40 cm depths under maize (Zea mays), wheat (Triticum aestivum), and alfalfa (Medicago sativa L.) cropping systems from the farmer’s field, in the Igdir Plain, eastern Turkey. Soil spatial variability was based on clay, silt, and sand, calcium carbonate (CaCO3) and organic matter, the pH, electrical conductivity, bulk density, aggregate stability and penetration resistance of the soil were determined. The data was analysed using both statistical and geostatistical approaches and suggested that the spatial distribution model and spatial dependence level varied significantly within the farm soils. Exponential, Gaussian, and spherical semivariogram models were found to be the best models to explain the spatial structure of the soil properties. Clay and sand, electrical conductivity, soil organic matter, bulk density, aggregate stability, and penetration resistance were found to be significantly different between the soil depths. The soil property ranges of the variogram were between 58.5 and 305.9 m and showed a moderate to strong spatial dependence. The development of spatial distribution maps for the soil variables analysed provided for a comparison to be made between the various soil properties and raises the possibility of understanding heterogeneity within the farm in the form of a regional representation. It may be concluded that these maps will assist in determining site-specific soil use and identifying the impact of soil management. [ABSTRACT FROM AUTHOR]

This study evaluates UVC light as an alternative to improve the microbiological quality of seeds intended for sprouting. UVC treatments with light exposure times up to 120 and 180 min were tested to reduce native bacterial population (NBP) in alfalfa, wheat, and chia seeds. The effects of the UVC light treatments on germination yield and rate, growth kinetics and antioxidant activity of sprouts were also evaluated. Results demonstrated that reductions of NBP after 180 min of UVC light exposure were dependent on the type of seed and their physical characteristics. The Weibull model demonstrated good fitness to experimental data (R2 >0.96) for the concave upward inactivation kinetics (n <1). Besides, the tested UVC light treatments did not affect the germination yield of the studied seeds and decreased the germination time to attain the commercial height of alfalfa and chia sprouts. The UVC light treatments applied on the studied seeds influenced positively the antioxidant properties when sprouting. The application of UVC light to alfalfa and wheat seeds destined for sprouting might be an alternative to improve their microbiological quality of seeds, without affecting their germination properties; while the nutritional benefits of its application, primordially focused to enhance its antioxidant properties of sprouts can be considered for chia and alfalfa seeds. • Effective inactivation of native microbiota of alfalfa and wheat seeds by UVC light. • UVC light treatments improves germination rate of alfalfa and chia seeds. • Antioxidant activity is enhanced by UVC light treatments of seeds when sprouting. [ABSTRACT FROM AUTHOR]

Simple Summary: A common nutritional strategy to reduce heat stress on dairy cows is to provide a more slowly degradable starch source that reduces the amount of heat generated during digestion. The aim of this experiment was to investigate the responses of late lactation dairy cows to cereal grain-based diets in a short-term heat challenge. Cows were offered a diet of alfalfa hay supplemented with either wheat grain (fast rumen degradable) or corn grain (slow rumen degradable). Individual cow measurements of feed intake, milk yield and composition, respiration rate, and body temperature were taken daily before, during and after a 4-day heat challenge, during which the cows were in individual controlled-climate chambers and exposed to air temperature up to 33 °C with 50% relative humidity. While exposed to the heat challenge during late lactation, cows that were offered corn grain had greater feed intake and tended to produce more energy-corrected milk but had lower respiration rates and similar body temperature to the cows offered wheat grain. The economic impact of feeding corn in place of wheat grain needs to be assessed before any comparative value of feeding corn grain or wheat grain can be determined. Cereal grains that differ in the rate and extent of ruminal fermentation differ in heat increment and may be used to improve thermoregulation during heat stress. This experiment investigated the responses of dairy cows in late lactation to a heat challenge when offered wheat-grain or corn-grain. Eighteen lactating cows, 220 ± 94 (mean ± standard deviation) days in milk, 3.7 ± 0.17 years of age and 558 ± 37 kg bodyweight, were allocated treatments containing 6 kg dry matter (DM)/day of wheat grain or 6 kg DM/day corn grain (9 per treatment) plus 14 kg DM/day of alfalfa hay. Measurements were made during a 7-day pre-challenge period at ambient conditions in individual stalls, during a 4-day heat challenge (temperature humidity index of 74 to 84) in individual controlled-climate chambers, then during a 7-day recovery period at ambient conditions in individual stalls. During the heat challenge, cows offered corn had lower respiration rates (p = 0.017) and greater feed intake (p = 0.021) but energy-corrected milk (p = 0.097) was not different to that of cows offered wheat. Feeding corn grain to dairy cows during a heat challenge reduced some of the negative impacts of heat stress, enabling the cows to consume more forage compared with supplementing with wheat grain. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the effects of vegetation type (Alfalfa and Wheat) and slope (5% and 20%) on runoff and drainage pollution in clay loam soil. Sampled soils were repacked in the box with one soil drainage outlet and one surface flow outlet and were cultivated by wheat or alfalfa. A solution containing 0.05 M KCl was poured quickly and uniformly, over the surface of each box, after plant growth. Simulated rainfall was applied to the soil box with the intensity of a constant rate of 64 mm h-1 for 2 hours immediately. Then the concentration of Cl- and K+ were measured in the collected samples of runoff and the drainage outlet. Results showed that the measured concentration of K+ was lower than the Cl- concentration as a result of its absorbable property. The breakthrough curves (BTCs) of Cl- and K+ showed that slope and vegetation type affected the transport of Cl- and K+. The peak of the BTCs for Cl- and K+ in runoff ranked in the order of wheat and 20% slope> alfalfa and 20% slope> wheat and 5% slope> alfalfa and 5% slope, and in the drainage changed to alfalfa and 5% slope> wheat and 5% slope> alfalfa and 20% slope> wheat and 20% slope. For each slope, the intensive vegetation cover of alfalfa than wheat considerably reduces Cl- or K+ pollution in runoff; whereas drainage development of larger and deeper root systems was the cause of higher leached concentrations for both tracers. Based on our research changes in soil surface vegetation cover from wheat to alfalfa are suggested in slope land to prevent surface water pollution; although other factors such as the climate, soil texture, and structure should also be considered. [ABSTRACT FROM AUTHOR]

Within Mediterranean cropping systems, legume forage crops that last up to 6 years or more (e.g., alfalfa) are replaced with cereal crops (e.g., wheat). The change from forage to cereal crops has negative climate and environmental impacts that must be addressed with mitigation actions. This study evaluated the synergies and tradeoffs between the ecosystem services provided by three management systems after forage legume. A field trial was set up from October 2017 to September 2019 on a 6-year-old alfalfa field subjected to the following management systems: (i) alfalfa termination followed by wheat for 2 years (WW, control); (ii) alfalfa termination followed by single amendment with 60 Mg ha−1 recalcitrant biochar and then by wheat for 2 years (WWB60); and (iii) extension of alfalfa for 2 years (AEXT). A range of regulating, supporting, and provisioning ecosystem services were assessed during the 2018 and 2019 cropping seasons. The results highlight that WWB60 can guarantee carbon sequestration without causing tradeoffs with other services, while AEXT can enhance soil conservation while not increasing soil greenhouse gas emissions. Future policies should support the WWB60 system if the goal is to increase the supporting services. Conversely, the AEXT system should be used if the goal is to increase the regulating and provisioning services. [ABSTRACT FROM AUTHOR]

Intercropping pasture with grain crops provides a strategy for diversifying cropping systems and establishing a foundation for mixed crop-livestock farming systems. Investigating the effects of strip design and nitrogen (N) application on interspecific interaction, crop yield, N use efficiency (NUE), and land equivalent ratio (LER) in dryland wheat/alfalfa intercropping. We conducted a four-year field experiment, which tested three intercrops, namely, 2-row wheat with 1-row alfalfa (I21), 4-row wheat with 2-row alfalfa (I42), and 8-row wheat with 4-row alfalfa (I84), as well as sole wheat (SW) and alfalfa (SA). N rates of 150 (HN) and 75 kg ha−1 (LN) were applied for wheat. Winter wheat exhibited earlier spring green-up than alfalfa and maintained dominance during co-growth. Over the four seasons, I21, I42, and I84 resulted in wheat yield (based on the wheat strip area) increases of 19.0%, 16.7%, and 24.0%, respectively, under HN, and 34.1%, 31.9%, and 43.4% under LN. Alfalfa growth was constrained during co-growth but recovered after the wheat harvest. Alfalfa in I42 and I84 maintained forage yield (based on the alfalfa strip area) as high as SA. Intercropping increased wheat NUE under both N conditions but did not significantly affect alfalfa NUE. I84 attained the highest LER of 1.01–1.14 and 1.11–1.25 under HN and LN respectively. Net revenue of I84 was lower than SA but three times higher than SW. Wide-strip wheat/alfalfa intercrop with low-N showed the best performance, which is promising in diversifying farming system and improving agricultural sustainability. • Wheat yield improvement was more significant under low nitrogen. • Intercropping increased both wheat ear density and 1000-grain weight. • Land equivalent ratio of wheat/alfalfa intercrop ranged in 0.79–1.31. • Wheat/alfalfa intercropping had higher yield and land advantage under low nitrogen. • Intercrop of 8-row wheat and 4-row alfalfa with low N was suggested for application. [ABSTRACT FROM AUTHOR]

The research presented in this paper was carried out during three years of study (2018-2020) and aimed at studying soil erosion and losses of humus and major macroelements (nitrogen, phosphorus, potassium) based on the precipitation regime that produced runoff on the slope. The research was carried out on a stagnic vertic preluvosoil with a slope of 4%, with a moderate acid reaction and a medium supply of nitrogen and potassium, and weak supply of phosphorus from Balota de Sus area, Dolj County, comprising 3 crops practiced in the area: wheat, corn, alfalfa compared to the field black (uncultivated) and spontaneous vegetation (natural). Following the researches, it was found that the most significant runoff on the slope was recorded in black fallow 471.98 mc/ha and corn 252.62 mc/ha, and the lowest were recorded in wheat 183.43 mc/ha and alfalfa 118.87 mc/ha (25.14% compared to the black fallow). Soil erosion, or soil losses, recorded high values also in the case of corn cultivation 6.84 t/ha (39.42%) and in the case of black fallow 17.35 t/ha (100%). The humus in the soil was lost in the largest quantities also in the corn crop 198.19 kg/ha (40.56%) and black fallow 488.58 kg/ha (100%) and in quite small quantities in the case of alfalfa 89.20 kg/ha (18.25 %). Nutrients in the soil have been lost, both by runoff water on sloping soil and by eroded soil, with higher amounts lost through eroded soil. [ABSTRACT FROM AUTHOR]

Purpose: Precrops exhibit vigorous deep root growth, especially when grown perennially. However, their contribution to accumulate essential nutrients derived from deeper soil layers in the topsoil has not been quantified. We determined the vertical distribution of phosphorous (P) and potassium (K) affected by contrasting root systems of 3 precrops and their effects on subsequently grown spring wheat. Methods: Three precrops (lucerne, chicory and tall fescue) were grown for 1, 2 and 3 years prior to spring wheat cultivation. We measured plant available soil P and K from 0 to 30 cm to 75–105 cm of soil depth after precropping. Root growth and crop performance of spring wheat as affected by precropping were measured in two repeated trials. Results: We observed maximum 22-fold higher root-length density (RLD; cm cm− 3) of taprooted chicory compared with fibrous-rooted tall fescue in the subsoil. There were significant increases in plant available K in the topsoil by 27 mg kg− 1 over the precrop duration between 1 and 3 years. Grain yield of subsequently grown spring wheat was significantly increased by 10 % and 14 % from 1 year to 3 year-treatments of lucerne and chicory, respectively. Similarly, significant increases in P uptake (7 % and 19 %) and K uptake (21 and 14 %) of spring wheat was noted for the same treatments. Conclusions: Our data suggest that there is potential for the yield of short-season cereals to be improved by increased soil nutrient bioavailability in the topsoil derived from deeper soil layers by the deep roots of perennial precrops. [ABSTRACT FROM AUTHOR]

Agricultural land management may influence crop nutritional quality. However, few studies have explored potential connections between crop quality with different land management strategies. We analyzed mineral and crude protein concentrations in spring wheat grain (Triticum aestivum L.) samples from a study in Mandan, ND conducted from 2006 to 2014. The study introduced a perennial forage phase into an annual spring wheat cropping system, in three to four replicates, and previously found yield benefits and enhanced soil parameters in the perennial forage treatments. We determined whether integrating a perennial forage phase into continuous wheat would also affect crop nutritional quality by measuring wheat grain mineral and protein concentrations. Crude protein concentration was greater (p <.05) when wheat followed alfalfa (Medicago sativa L.) and increased linearly after 2–5 yr of established alfalfa. We observed comparable wheat grain crude protein and mineral concentrations between continuous annually fertilized wheat and unfertilized wheat following perennial forages. Negative correlations (p <.001) were observed between wheat grain yield and crude protein, potassium (K), magnesium (Mg), nickel (Ni), phosphorus (P), sulfur (S), and zinc (Zn) concentrations. Discriminate multivariate analyses showed, with 96% predictive accuracy, that differences in crude protein and mineral concentration were largely driven by year of wheat harvest. Differences between harvest years were likely due to timely precipitation at critical Growth Stage 3, during spikelet development. Study outcomes highlighted the important role of perennial forages and environmental factors to influence protein and mineral concentration in spring wheat grain. Core Ideas: Perennial forages benefit annual cropping systems. Wheat grain samples were analyzed for mineral and protein concentration. Protein was greater when wheat followed alfalfa versus intermediate wheatgrass. Grain quality was similar between annual cropping and wheat following perennials. Grain mineral and protein concentrations were influenced by environmental factors. [ABSTRACT FROM AUTHOR]

The assessment of soil suitability for sustainable intensive agriculture is important for the selection of land suitable for agricultural production with the least economic and environmental costs. This study was directed to evaluate agricultural soil suitability in the south of Hail province, Saudi Arabia to suggest alternative crops of alfalfa using the Agricultural Land Evaluation System for arid regions (ALES-Arid) model and Geographic Information System (GIS). The study area covers about 77558 ha and 111 soil samples were collected from 37 profiles and 37 groundwater samples were analyzed for physical, chemical and fertility properties. To evaluate land suitability for selected crops, the FAO guideline was used and also to analyze and map soils within the study area, the GIS was employed. The main research goals were to characterize the soil and water resources of the study area, in order to plan the best alternative crops of alfalfa using land evaluation facilities for different purposes (capability and suitability). The results indicated that the soils of the area are characterized by sandy loam texture, low fertility, low total carbonate and most of the area have moderate to high salinity soil. Capability classes of the area are C3 and C4 which covers about 89.19% and 10.81% of the total area, respectively. The most fertile classes were situated in C2 and C3 which covers 37.84 and 40.54% of the area with phosphorus and potassium limitation. The land suitability results show that 99.68, 97.18 and 85.37% of the area is classified as S1 (highly suitable) for wheat, barley and alfalfa, respectively; while 98.91% of the area is classified as S3 (marginally suitable) for maize. From the obtained data, growers are advised to cultivate barley or wheat in winter and maize in summer instead of alfalfa, in order to save irrigation water. This is also because the expected productivity of either wheat or barley is high. It is important for decision makers to determine the best way of using land for agricultural purposes, since it serves as a decision and planning support. [ABSTRACT FROM AUTHOR]

The intercropping system has shown great advantages in adverse environments due to balanced use of diverse resources and promotion of sustainable productivity. However, identifying an optimal intercropping practice is still urgently needed in resources-limited areas, i.e., some perennial legume crop and annual cereal crop intercropping in arid areas. This study tested a hypothesis that spring wheat/alfalfa strip intercropping under irrigation could improve land and irrigation water uses compared to sole spring wheat or alfalfa, and, therefore, would ensure reliable agronomic and economic benefits in the arid areas. A three years field experiment was conducted to investigate the yield performance, resource use and economic benefit of irrigated spring wheat/alfalfa strip intercropping in the inland arid area of northwestern China. The intercropping systems with different intercropping ratios were established, including four rows of alfalfa intercropped with twelve rows of spring wheat (W12A4) and with eight rows of spring wheat (W8A4), both of which were compared with sole spring wheat (SW) and sole alfalfa (SA). All these cropping systems were provided with irrigation at four levels: 450 (I450), 360 (I360), 270 (I270), and 180 mm (I180). The grain yield of spring wheat first increased and then decreased with the decrease in irrigation amount, with maximum yield achieved at I360. However, dry matter yield of alfalfa decreased with decreasing irrigation amount. Land equivalent ratio (LER) of the intercropping system was 0.72–1.05, suggesting this intercropping may not effectively save farmland. The W12A4 had higher grain yield, total dry matter accumulation, LER, and irrigation water use efficiency than W8A4. Except for the establishing year, the intercropping system produced 3.37–39.82% higher net income than SW in the other two years. There were no difference in net income and output/input ratio between W12A4 and W8A4. Spring wheat/alfalfa strip intercropping can be used as a productive and sustainable strategy in the arid areas, which can improve irrigation water use, produce higher grain and forage yield, and increase net income. The W12A4 with 360 mm irrigation could be extensively used in the inland arid area of northwestern China. It is recommended that this spring wheat/alfalfa intercropping should be adopted in this and similar arid areas in the world to promote sustainable development of agriculture and animal husbandry in the context of increasing population, resource constraint and climate change. • More intercropping practices are still urgently needed in resources-limited areas. • Spring wheat/alfalfa intercropping had higher irrigation water use efficiency than sole spring wheat. • The intercropping system produced more net income than sole spring wheat. • This intercropping system had less advantage for farmers in saving farmland. • Strip intercropping of 12-row spring wheat and 4-row alfalfa with 360-mm irrigation was recommended in arid areas. [ABSTRACT FROM AUTHOR]

Landscape complexity influences soybean aphid suppression by generalist predators in North America, but the role of adjacent habitats as sources of these predators has not been studied directly. We quantified movement of aphidophagous predators between soybean and five adjacent habitats common in Manitoba using bi-directional Malaise traps. To test the contribution of predators from neighboring habitats to soybean aphid suppression, we performed experimental manipulations in adjacent soybean and alfalfa fields and monitored the movement of sevenspotted lady beetles, Coccinella septempunctata, using mark-release-recapture experiments. The identity of adjacent habitats affected the net movement of predators into soybean. The most abundant predators were hover flies (Diptera: Syrphidae), moving from woodlands to soybean. Similar (but non-significant) trends were found for lady beetles, minute pirate bugs, and green and brown lacewings. There was also a net movement of hover flies and green lacewings from soybean to canola. Lady beetles showed higher bidirectional movement in alfalfa and wheat borders than in woodland and canola borders in a high lady beetle abundance year. Soybean aphid populations in predator exclusion cages were 21- to 122- fold higher than populations exposed to predators, both in alfalfa and soybean fields. Aerial predators provide similar levels of aphid suppression as aerial and epigeal predators combined. Mark-release-recapture experiments showed high dispersal of C. septempunctata between soybean and alfalfa, with a net movement towards alfalfa, probably due to the lack of aphids in soybean. These results demonstrate that predator assemblages from both soybeans and alfalfa can suppress soybean aphids. Our findings indicate that the type of adjacent habitat and predator identity affect the directionality of predator movement into soybean. This study suggests that information on predator movement can be used to design the distribution of crops and natural habitats in agricultural landscapes that maximize pest control services. [ABSTRACT FROM AUTHOR]

Maintaining soil available nitrogen levels in organic systems is a particularly large challenge in the semiarid inland Pacific Northwest. This study compared the nitrogen fertility effects of alfalfa forage, winter pea green manure, and poultry manure for organic wheat production. Soil inorganic nitrogen and wheat yields were the greatest following poultry manure application and the least following winter pea green manure and alfalfa forage, but winter pea biomass production was positively correlated with wheat yields. Soil total nitrogen (TN) was the greatest following alfalfa, but more research is needed to identify practices that increase the release of nitrogen from legume residues in semiarid organic systems. [ABSTRACT FROM PUBLISHER]

Integration of perennial forages in annual cropping systems can expand ecosystem service benefits to agricultural landscapes. Such benefits are frequently derived from changes to soil properties. Unfortunately, there is limited guidance for agricultural producers regarding the length of time needed to accrue soil condition improvements under perennial forages, particularly for semiarid regions. The objective of this study was to quantify soil responses to perennial grasses, legumes, and grass–legume mixtures over a 5-yr year period in a semiarid region. Select soil physical and chemical properties were measured within five perennial forage treatments and under annual cropping over a 5-yr period on a Parshall fine sandy loam near Mandan, ND. Treatment effects on soil properties were limited to the surface 10 cm. Differences in soil properties between spring wheat (Triticum aestivum L.) and perennial forages were most frequent following the fourth stand year. Compared with spring wheat, perennial forages mitigated soil acidification (by 0.26–0.65 pH units), reduced soil bulk density (by 0.04–0.08 Mg m–3), and increased particulate organic matter (POM) (by 0.41 g C kg–1) and water-stable aggregates (by 3.8%). Among perennial forages, intermediate wheatgrass (Thinopyrum intermedium L.) and intermediate wheatgrass–field pea (Pisum sativum L) mixture followed by alfalfa (Medicago spp.) reduced soil bulk density (by 0.06–0.11 Mg m–3) and increased POM (by 0.24–0.92 g C kg–1) compared with alfalfa following 4- and 5-yr perennial forage stands. While these outcomes suggest perennial forages can improve the near-surface soil condition, accrual of improvements may be slow and subtle in semiarid regions. [ABSTRACT FROM AUTHOR]

The long-term understanding of the carbon budget of cropping systems needs to consider varying meteorological conditions, site/soil conditions, crop selection, and management decisions. On the Canadian Prairies, a variety of crops are used in yearly rotation, often not repeating the same crop within a 3-year period. We measured net ecosystem production (NEP) in two cropping systems in southern Manitoba, Canada, for the 2006–2016 period. One system had continuous annual crops, whereas the other had a perennial phase for 4 years. NEP was calculated using the flux-gradient method, where the carbon dioxide gradient was measured with a tunable-diode laser analyser and the transfer coefficient was based on momentum similarity theory with inputs from sonic anemometer-thermometers. NEP varied from −100 (source) to +300 (sink) g C m −2 y −1 among four adjacent 4-ha fields and 10 years, depending on annual crop (corn, faba, spring wheat, barley, rapeseed, soybean) and environmental conditions. There was no period of 3 years or greater when NEP in the continuous annual crop rotation was different from carbon neutral. Inserting a 4-year perennial phase of an alfalfa/grass mix created a statistically significant carbon sink for NEP (P = 0.04), but the perennial period itself was carbon neutral. Enhanced ecosystem respiration was observed following termination of the perennial crop. Harvest practices varied from no harvest (in the establishment year of the perennial crop), grain removal only, grain + straw removal, and straight cutting of green biomass for silage. Once harvest removals were included, 3 of the 4 fields were carbon neutral, but one annual field had net carbon losses for some periods. Ecosystem respiration averaged about twice as large as harvest removals. Net carbon (mean ±S.E.) over the 11-year period for the annual cropping system (−78 ± 51 g C m −2 y −1 ) was not different from the annual-perennial system (−48 ± 47 g C m −2 y −1 ). [ABSTRACT FROM AUTHOR]

Our previous study showed that smoke derived from alfalfa (Medicago sativa) caused different germination responses compared with that from prairie hay (Festuca hallii) and wheat straw (Triticum aestivum), but the mechanism remained unclear. In this study, we used Salad Bowl lettuce (Lactuca sativa) as a quick bioassay to trace the active compounds in each of these three smoke solutions. Column chromatography and high performance liquid chromatography (HPLC) were used to separate and identify active fractions. Seeds of four species from Fescue Prairie were primed for 24 h at room temperature in darkness using serial dilutions of separated active fractions, as well as karrikinolide (KAR1). After priming, seeds were dried at room temperature in darkness for 7 days and subsequently incubated at 10/0°C or 25/15°C in 12 h light–12 h dark or 24 h darkness for 49 days. KAR1 was in the smoke made from prairie hay, and wheat straw, but was absent in alfalfa smoke. Priming in KAR1 solutions increased germination of three native species. Priming in highly concentrated KAR1 reduced radicle length of Cirsium arvense, the only non-native species. Even though KAR1 has the potential to enhance regeneration of native species in the Fescue Prairie, KAR1 is not universally present in smoke derived from different plant materials. Unknown compound(s) in smoke derived from legumes remain to be identified. [ABSTRACT FROM AUTHOR]

Land suitability assessments can provide useful information to help optimize agricultural land use. Due to the current lack of appropriate land management practices in the Fakkeh region, southwest Iran, a land suitability evaluation study for key agricultural crops, including wheat, alfalfa, maize and barley, covering 43,700 ha was undertaken. Qualitative evaluation was carried out using two methods, the simple limitation and parametric methods (Storie and square root method), to compare land and climate characteristics with crop needs. The most important limiting factors in wheat, alfalfa and barley production included the physical properties of the soil, especially light soil texture. The major limiting factors in maize production were low relative humidity and high n/N ratio during the plant growth period, light soil texture, soil salinity and alkalinity. [ABSTRACT FROM AUTHOR]

The effect of cropping system on the distribution of organic carbon (OC) and nitrogen (N) in soil aggregates has not been well addressed, which is important for understanding the sequestration of OC and N in agricultural soils. We analyzed the distribution of OC and N associated with soil aggregates in three unfertilized cropping systems in a 27-year field experiment: continuously cropped alfalfa, continuously cropped wheat and a legume-grain rotation. The objectives were to understand the effect of cropping system on the distribution of OC and N in aggregates and to examine the relationships between the changes in OC and N stocks in total soils and in aggregates. The cropping systems increased the stocks of OC and N in total soils (0–40 cm) at mean rates of 15.6 g OC m-2 yr-1 and 1.2 g N m-2 yr-1 relative to a fallow control. The continuous cropping of alfalfa produced the largest increases at the 0–20 cm depth. The OC and N stocks in total soils were significantly correlated with the changes in the >0.053 mm aggregates. 27-year of cropping increased OC stocks in the >0.053 mm size class of aggregates and N stocks in the >0.25 mm size class but decreased OC stocks in the <0.053 mm size class and N stocks in the <0.25 mm size class. The increases in OC and N stocks in these aggregates accounted for 99.5 and 98.7% of the total increases, respectively, in the continuous alfalfa system. The increases in the OC and N stocks associated with the >0.25 mm aggregate size class accounted for more than 97% of the total increases in the continuous wheat and the legume-grain rotation systems. These results suggested that long-term cropping has the potential to sequester OC and N in soils and that the increases in soil OC and N stocks were mainly due to increases associated with aggregates >0.053 mm. [ABSTRACT FROM AUTHOR]

The increasing demand for high-quality animal protein calls for parts of cereal cropping systems converting to forage or forage-livestock integrated systems. This study aimed at evaluating potential environmental impacts of this transition at the farm level on the Loess Plateau of China through a life cycle assessment (LCA) approach. Four dominating crops: alfalfa, wheat, grain maize and silage maize were studied based on the ten impact categories. Based on standard unit land area (1 ha) and timestamp (2018–2020) settings, alfalfa production indicated the lowest environmental impact in nine categories compared to other crops, while wheat indicated better performance in seven of ten impact categories than other crops except alfalfa. With respect to the environmental loads of grain maize and silage maize production, both systems were very comparable. Because of the common adoption of open-land burning of straws (mainly for fuel and winter heating) in the local region, the respiratory inorganics and photochemical oxidant formation potential impact of alfalfa and silage maize per hectare produced is much lower than those of wheat and grain maize. Great differences in environmental impacts between the two types of cropping systems (cereal vs forage) indicate that transitioning from cereal to forage production should effectively reduce air pollution and enhance environmental sustainability on the Loess Plateau. Besides, uncertainty and variability of LCAs results were analyzed in this study. [Display omitted] • Environmental impacts of four types of cropping systems were compared by land unit. • Impact variability among farms was analyzed through 607 LCAs. • Performance of most impact categories was alfalfa>wheat>silage maize>grain maize. • Forage cropping systems incurred less air pollution than cereal systems. [ABSTRACT FROM AUTHOR]

The increasing demand for high-quality animal protein calls for parts of cereal cropping systems converting to forage or forage-livestock integrated systems. This study aimed at evaluating potential environmental impacts of this transition at the farm level on the Loess Plateau of China through a life cycle assessment (LCA) approach. Four dominating crops: alfalfa, wheat, grain maize and silage maize were studied based on the ten impact categories. Based on standard unit land area (1 ha) and timestamp (2018–2020) settings, alfalfa production indicated the lowest environmental impact in nine categories compared to other crops, while wheat indicated better performance in seven of ten impact categories than other crops except alfalfa. With respect to the environmental loads of grain maize and silage maize production, both systems were very comparable. Because of the common adoption of open-land burning of straws (mainly for fuel and winter heating) in the local region, the respiratory inorganics and photochemical oxidant formation potential impact of alfalfa and silage maize per hectare produced is much lower than those of wheat and grain maize. Great differences in environmental impacts between the two types of cropping systems (cereal vs forage) indicate that transitioning from cereal to forage production should effectively reduce air pollution and enhance environmental sustainability on the Loess Plateau. Besides, uncertainty and variability of LCAs results were analyzed in this study. [Display omitted] • Environmental impacts of four types of cropping systems were compared by land unit. • Impact variability among farms was analyzed through 607 LCAs. • Performance of most impact categories was alfalfa>wheat>silage maize>grain maize. • Forage cropping systems incurred less air pollution than cereal systems. [ABSTRACT FROM AUTHOR]

Polycyclic Aromatic Hydrocarbons (PAHs) are diverse organic contaminants released into the environment by both natural and anthropogenic activities. These compounds have negative impacts on plants growth and development. Although there are many reports on their existence in different parts of plant, their uptake and translocation pathways and mechanisms are not well understood yet. This paper highlights the uptake, translocation and accumulation of PAHs by wheat, sunflower and alfalfa through an experimental study under controlled conditions. Seeds were cultivated in a soil containing 50 mg/kg of phenanthrene and fluorene and their concentrations in plants roots and shoots were determined using a gas chromatograph after 7 and 14 days. The results showed that phenanthrene and fluorene concentrations in the treated plants were increased over the time. PAHs bioavailability was time and species dependent and generally, phenanthrene uptake and translocation was faster than that of fluorene, probably due to their higher Kow. Fluorene tended to accumulate in roots, but phenanthrene was transported to aerial parts of plants. [ABSTRACT FROM PUBLISHER]

Ractopamine is a beta adrenergic agonist used as a growth promoter in swine, cattle and turkeys. To test whether ractopamine has the potential to accumulate in plants grown in contaminated soil, a greenhouse study was conducted with alfalfa ( Medicago sativa ) and wheat ( Triticum aestivum ) grown in two soils having different concentrations of organic matter (1.3% and 2.1%), amended with 0, 0.5, and 10 μg/g of ractopamine. Plant growth ranged from 2.7 to 8.8 g dry weight (dw) for alfalfa, and 8.7 to 40 g dw for wheat and was generally greater in the higher organic matter content soil. The uptake of ractopamine in plant tissues ranged from non-detectable to 897 ng/g and was strongly dependent on soil ractopamine concentration across soil and plant tissue. When adjusted to the total fortified quantities, the amount of ractopamine taken up by the plant tissue was low, < 0.01% for either soil. [ABSTRACT FROM AUTHOR]

Background: Polycyclic aromatic hydrocarbons (PAHs) are widespread organic pollutants releasedinto the environment by both natural and anthropogenic processes. PAHs can negatively affectdifferent aspects of plant growth and development. However, the mechanisms of PAHs effects andphysiological response of plants to PAHs have not been adequately studied. Accordingly, the aim ofthis study was evaluation of the germination, growth and physiological responses of wheat,sunflower and alfalfa to phenanthrene toxicity. Material and Methods: This experiment was conducted as a pot culture of plants using a completely randomised design (CRD) with four replications. Plants were cultivated in soil containing 50 and 100 mg kg-1 of phenanthrene for 14 days under greenhouse conditions. All biochemical assays were performed spectrophotometrically after the determination of growth parameters.Results: Soil contamination with phenanthrene differently decreased seed germination and the subsequent seedling growth of plants. Alfalfa showed the highest resistance at both the seed germination and seedling growth phases. Wheat and sunflower were the most sensitive species at the seed germination stage and seedling growth phase, respectively. Phenanthrene contamination induced oxidative stress in plants and POD was determined to be the important enzyme involved in ROS detoxification.Conclusions: Phenanthrene effects on seed germination, seedling growth and physiological parameters of plants are species-dependent. The induction of oxidative stress and decrease in photosynthetic pigments content are two of the reasons for lower plant growth in phenanthrenecontaminated soil, and POD was an important enzyme in the detoxification of ROS. At least in some species, the higher resistance at seed germination could be followed by the higher resistance of seedlings to PAHs. [ABSTRACT FROM AUTHOR]

Non-destructive biomass estimation of vegetation has been performed via remote sensing as well as physical measurements. An effective method for estimating biomass must have accuracy comparable to the accepted standard of destructive removal. Estimation or measurement of height is commonly employed to create a relationship between height and mass. This study examined several types of ground-based mobile sensing strategies for forage biomass estimation. Forage production experiments consisting of alfalfa (Medicago sativa L.), bermudagrass [Cynodon dactylon (L.) Pers.], and wheat (Triticum aestivum L.) were employed to examine sensor biomass estimation (laser, ultrasonic, and spectral) as compared to physical measurements (plate meter and meter stick) and the traditional harvest method (clipping). Predictive models were constructed via partial least squares regression and modeled estimates were compared to the physically measured biomass. Least significant difference separated mean estimates were examined to evaluate differences in the physical measurements and sensor estimates for canopy height and biomass. Differences between methods were minimal (average percent error of 11.2% for difference between predicted values versus machine and quadrat harvested biomass values (1.64 and 4.91 t·ha-1, respectively), except at the lowest measured biomass (average percent error of 89% for harvester and quad harvested biomass < 0.79 t·ha-1) and greatest measured biomass (average percent error of 18% for harvester and quad harvested biomass >6.4 t·ha-1). These data suggest that using mobile sensor-based biomass estimation models could be an effective alternative to the traditional clipping method for rapid, accurate in-field biomass estimation. [ABSTRACT FROM AUTHOR]

Salt accumulation has a negative effect on microorganisms, but plant residues may enhance the microbial activity and biomass. An experiment was conducted over 50 days to evaluate the effect of wheat and alfalfa residues on microbial activity and biomass and nitrogen (N) and phosphorus (P) availability in sandy and clayey soils at different salinity levels. Equivalent amounts of calcium (Ca+2) and sodium (Na+) salts were added to both soils. Values of electrical conductivity (EC1:5), denoted S1, S2, and S3 in each soil, were 0.16, 1.10 and 1.98 dS m−1in the sand and 0.19, 0.82 and 1.75 dS m−1in the clay. Residues of wheat and alfalfa were added at 2% (w/w). Cumulative respiration and microbial biomass decreased with increasing salinity, but with residue addition they increased with a greater rate in amended sandy soil than in clay soil, with a more pronounced effect for alfalfa than for wheat residue. After 10 days, with wheat residue available N values were 113, 86, and 71μg in the clay and 144, 114, and 94μg g−1soil in the sand in S1, S2, and S3, respectively. Relative to wheat residue, alfalfa residue increased N availability by 9, 13, and 19% and 22, 24, and 24% in the clay and in the sand in S1, S2, and S3, respectively. Compared to the control, in the clay P availability increased by 33, 57, and 100% with wheat residue and by 58, 128, and 175% with alfalfa residue, whereas in the sand it increased by 92, 45, and 40% with wheat residue and by 130, 145, and 280% with alfalfa residue in S1, S2, and S3, respectively. Availability of N and P increased from day 10 to day 50 in both soils, but with different magnitudes. Residue addition can increase microbial activity and nutrient availability in saline soils, particularly in coarser textured soils. [ABSTRACT FROM AUTHOR]

Slow pasture growth rates during winter limit the potential gross margins from autumn and early winter lambing in southern New South Wales (NSW) by limiting stocking rates and/or increasing supplementary feed requirements. Dual-purpose crops can reduce the winter feed gap in mixed-farming systems by increasing the available feed in winter. The simulation software AusFarm was used to model a mixed-farming system at Wagga Wagga with Merino ewes joined to terminal sires and grazing lucerne-subterranean clover pasture over a 41-year period. A paddock of dual-purpose wheat was then added to the system, and ewes were allowed to graze the wheat crop when feed on offer reached 850 kg DM/ha and before GS31. Weaned lambs were sold after late August if lamb growth rates fell below 20 g/head.day, mean lamb weight reached 45 kg or production feeding of lambs was required. Lambing in June resulted in the highest median gross margin whether or not ewes were able to graze the wheat crop during winter. Grazing of a dual-purpose wheat crop resulted in greater proportional increases in gross margins as stocking rate was increased, increased lamb production and reduced supplementary feeding costs, and reduced interannual variability in gross margin returns. Grazing dual-purpose wheat provides high quality feed for livestock at a time of year when pasture growth rates in southern Australia may be slow, and farmers may therefore consider changing their time of lambing to exploit this. Simulation modelling of a Merino ewe flock producing first-cross lambs and grazing lucerne-based pastures identified that the optimal time of lambing, in terms of highest median gross margin over the long-term, was not changed by inclusion of crop grazing in winter. Allowing ewes to graze a wheat crop in winter increased producer returns and reduced supplementary feeding requirements and the variability of returns. [ABSTRACT FROM AUTHOR]

• Including alfalfa forage with cereal forage diets increases dietary Ca, Mg and Na • In all treatments, plasma Mg, Na, K and P decreased throughout the study, but Ca increased • Supplementation with Na and Mg is required, including when alfalfa is provided. The development of perennial wheat is proposed to increase resource-use efficiency and sustainability of crop production. Annual dual-purpose winter wheat and perennial wheat offer grazing potential, however they both have mineral imbalances due to excess forage K and deficient Na, which may lead to metabolic diseases such as hypocalcaemia and hypomagnesaemia. Notwithstanding a low forage Na concentration, it was hypothesised that the addition of forage lucerne (alfalfa), high in forage Ca and Mg, may overcome calcium and magnesium deficiencies of the wheat varieties. A pen feeding study was conducted using 10-month-old Poll Dorset × Merino ewe lambs (46.4 ± 1.8 kg) to test the effect on plasma and urine mineral status with the addition of lucerne to perennial wheat or annual wheat forage. The lambs (n = 48) were individually fed one of four diets, including perennial wheat (PW), annual wheat (W), perennial wheat + lucerne (alfalfa) (PW + L) or annual wheat + lucerne (W + L) and feed intake was calculated daily. Individual blood and urine sampling commenced on entry to the pens and were repeated at 7-day intervals for 3 further weeks. The addition of lucerne increased the dietary supply of Ca, Mg and Na and decreased K and P. When compared to W, PW offered more Ca, Mg, K, and less Na and P. There were mineral intake differences over time (P < 0.001) for all minerals. All diets offered high dietary cation anion difference (45.0 – 94.9), K: (Na + Mg) (7.3 – 12.8), K: Na (305 – 1137) ratios, while the addition of lucerne increased the Ca: P ratio and improved the K: (Mg + Ca) (Tetany index). Plasma Mg, Na, K and P declined significantly throughout the study, under all diets, to varying degrees. In Week 1, plasma Mg was significantly lower in PW lambs when compared to all other diets, but no further diet effects were observed thereafter. By contrast, plasma Ca increased throughout the study, but without dietary effects. The urinary excretion of Mg was higher with the addition of lucerne in the PW + L and W + L diets after 1-week, although this effect declined in subsequent weeks. The excretion of Ca, Na and P was very low in urine and decreased, while K excretion increased during the study. Taken together the results indicate that the greater dietary intake of Ca, Mg and Na due to the addition of lucerne was insufficient to overcome the primary mineral imbalance of high dietary K and low Na in the cereal forages. Furthermore, the addition of lucerne to the diet further decreased P intake and greatly increased the Ca: P ratio. Our calculations suggest lambs grazing any of the diets in the present study still required supplementation with Na and Mg, but the addition of lucerne alleviated the need for Ca supplementation. The need for supplementation with a source of dietary P requires further investigation. [ABSTRACT FROM AUTHOR]

To investigate the effect of plants on soil water repellency (SWR), two column experiments with wheat ( Triticum aestivum) and alfalfa ( Medicago sativa) with a growing period of three months had been carried out under constant and near-natural climatic conditions. Model soils with defined wettability were created by mixing a natural sandy loam subsoil with different proportions of a wettable and a hydrophobized pure quartz sand, resulting in a wettable model soil and three model soils with increasing level of subcritical SWR (initial contact angle CA > 0° and < 90°). Results showed a significant decrease of the mean CA after the experiments compared to the initial CA while the mean CA was constant for plant free columns used as a reference. CA as a function of depth in some cases showed a depth dependent variation with decreased CA at the bottom or as well at top and bottom. The deviation from the initial CA was most pronounced for wheat under constant climatic conditions. Changes in CA could be related to changes in pH, i.e., CA was decreased and pH increased. Subcritical WR at the beginning of the growth period affected significantly the moisture content profiles during the entire growing season as well as plant dry mass production. We expect that plant root exudates of plants widely used for foot production cause directly or indirectly pH-related modifications of the WR level in the root zone dependent on plant species and the ambient climatic conditions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Lithium and bromide transport in soil columns and saturated condition were studied. [•] Pore networks in soil under alfalfa resulted in accelerated solute transport. [•] The breakthrough sequence justified the macropore flow in the treatments. [•] The strength of preferential flow can be measured by the relative 5% arrival time. [ABSTRACT FROM AUTHOR]

The sustainability of winter wheat (Triticum aestivum L.) − summer maize (Zea mays L.) rotation (W − M), which is commonly practiced in the North China Plain (NCP), is threatened by severe groundwater deficits and environmental pollution due to excessive nitrogen (N) applications. Considering the need for protein-rich forages by local livestock operations and the environmental benefits of growing perennial legumes, we propose that an alfalfa (Medicago sativa L.)-based system is worth introducing for field practice in the NCP. An integrated evaluation was used in this four-year study to compare the agronomic, economic, and environmental performances of the following four cropping patterns: alfalfa monoculture (AA), alfalfa and silage maize intercropping with or without N input which is designed for local climate condition, maize monoculture with or without N input which is much-discussed as a resources-saving substitution and commonly practiced W − M. W − M obtained the highest aboveground dry matter (DM) productivity (P < 0.05) based on the highest irrigation water and N fertilizer consumption (P < 0.05) which caused considerable soil mineral N (Nmin) accumulation. The production cost of maize monoculture was the lowest as well as the DM yield, nitrogen accumulation and the net revenue compared with other systems (P < 0.05), moreover, there was a great risk of N losses during the offseason period. The alfalfa and silage maize intercropping with a low N input (120 kg ha−1 which is close to local practice for maize season) achieved 26.6%–34.9% more DM yield compared with AA and maize monoculture, and 12.5%–163.9% more N output compared with W − M and maize monoculture during four experimental years with same total economic revenue as W − M and AA did. The N input in alfalfa and silage maize intercropping dramatically improved the system productivity by assisting intercropped maize growth while did not lead to excessive Nmin accumulation within 0–210 soil layer compared with the intercropping system without N addition. The planting of alfalfa would not affect the water storage in the 0–60 soil layer after maize harvesting each year. For the effects of interspecific competition, the production of the intercropped alfalfa and maize was significantly decreased in 2020 and a three-year period of production is recommended for optimal use of the alfalfa and silage maize intercropping. Alfalfa and silage maize intercropping with an appropriate N input, which acquired comprehensive performances in terms of productivity, environmental impacts as well as economic profits, would be an optimal alternative system in the NCP. The alfalfa and silage maize intercropping with an appropriate N input (A + M), which achieved high dry matter yield, nitrogen uptake and net revenue with the lowest irrigation water and nitrogen fertilizer use, would be an optimal alternative system in the North China Plain. [Display omitted] • The wheat–maize rotation (W – M) in the North China plain is profitable but has inevitable negative environmental impacts. • Alfalfa and maize intercropping (A + M) was proposed for the high protein productivity and the adaptability to climate. • The agronomic, economic, and environmental performances were compared among A + M, W – M, and monoculture systems. • A + M was more productive than monoculture, and consumed lower groundwater and nitrogen than W–M without net revenue loss. • A + M would be an optimal alternative system in the North China Plain for its comprehensive performances. [ABSTRACT FROM AUTHOR]

The effect of rainfall intensity, slope gradient, initial soil moisture, and vegetation cover on runoff intensity, and its progress were investigated using simulated rainfall. Various surface treatments of soil packed into bins were examined, namely bare ground and plantings with purple medic (Medicago sativa L.), spring wheat (Triticum aestivum L.), or ryegrass (Lolium perenne L.). Five different rainfall intensities (0.5, 0.75, 1, 1.5, and 2 mm min-1 [0.02, 0.03, 0.04, 0.06, and 0.08 in min-1]) and four different slope gradients (5°, 10°, 15°, and 20°) were studied. The main results were as follows. (1) There was a positive linear relationship between mean runoff intensity and rainfall intensity, gradient, and initial soil moisture, while there was a negative exponential relationship between mean runoff intensity and vegetation cover. (2) The piecewise function approach was used to determine effective vegetation cover values; these were found to be 52%, 62%, and 73% for purple medic, spring wheat and ryegrass, respectively. (3) Runoff intensity increased with increasing rainfall duration; the relationship was logarithmic, and the time to stable runoff was proportional to gradient but inversely proportional to rainfall intensity and initial soil moisture. (4) The function describing the relationship between runoff intensity and rainfall duration was γ = aeb/x (b < 0) for limited vegetation cover (<60%) and γ = a + bln(x) for more dense vegetation cover (>60%). [ABSTRACT FROM AUTHOR]

An analysis of the sensitivity of synthetic aperture radar (SAR) backscatter (σo) to crop and soil conditions was conducted using 57 RADARSAT-2 C-band quad-polarized SAR images acquired from April to September 2009 for large fields of wheat, barley, oat, corn, onion, and alfalfa in Barrax, Spain. Preliminary results showed that the cross-polarized σHVo was particularly useful for monitoring both crop and soil conditions and was the least sensitive to differences in beam incidence angle. The greatest separability of barley, corn, and onion occurred in spring after the barley had been harvested or in the narrow time window associated with grain crop heading when corn and onion were still immature. The time series of σo offered reliable information about crop growth stage, such as jointing and heading in grain crops and leaf growth and reproduction in corn and onion. There was a positive correlation between σo and the Normalized Difference Vegetation Index for onion and corn but not for all crops, and the impact of view direction and incidence angle on the time series was minimal compared to the signal response to crop and soil conditions. Related to planning for future C-band SAR missions, we found that quad-polarization with image acquisition frequency from 3-6 days was best suited for distinguishing crop types and for monitoring crop phenology, single- or dual-polarization with an acquisition frequency of 3-6 days was sufficient for mapping crop green biomass, and single- or dual-polarization with daily image acquisition was necessary to capture rapid changes in soil moisture condition. [ABSTRACT FROM AUTHOR]

Abstract: Dry spells during the summer period affecting water uptake and plant growth in central Europe may occur more frequently in the future due to climate change. Improving the ability of crops to take up water from deeper soil layers is a potential strategy to secure water supply. The objective of this paper is to report on the effect of different preceding fodder crops on root growth and water uptake of spring wheat from the subsoil. Water extraction and root length density during grain filling of spring wheat were observed between anthesis and maturity in six different soil depths (0–15, 15–45, 45–60, 60–75, 75–90 and 90–105cm) and with four different preceding crops: 1 year of fescue (Fes1Y), 2 years of chicory (Chi2Y), 2 years of lucerne (Luc2Y) and 3 years of chicory (Chi3Y). While there was no difference in total water extraction by wheat in the four crop sequences, water extraction from the deepest layer (90–105cm) was significantly higher after 2 years of lucerne (Luc2Y). This was consistent with the root length densities measured in the 90–105 layer, which were 82, 89 and 112% higher in Luc2Y as compared to Fes1Y, Chi2Y and Chi3Y, respectively. Results suggest that lucerne as preceding crop supports deeper rooting and higher rooting density of following spring wheat enhancing access to water in deeper soil layers in response to prolonged dry spells. Effects facilitating root penetration like improved soil structure and higher nitrogen availability after lucerne are discussed. We conclude that suitable crop rotations with lucerne might be a cost-effective adaptation measure to overcome drought stress. [Copyright &y& Elsevier]

The aim of this study was to evaluate the possible effect of pre-fermented juice (PFJ) on the fermentation quality and nutritive value of first-cut lucerne ( Medicago sativa L.) silage. The PFJs were prepared using barley (B), wheat (W) and grass herbages (G). Both fresh (PFJ-B, PFJ-W and PFJ-G) and frozen (PFJ-B, PFJ-W and PFJ-G) PFJs were examined. Frozen PFJs were prepared by freezing fresh PFJs at −22°C with 20% glycerol (v/v). Treatments of lucerne silage included (1) control; (2) silage treated with PFJ-B; (3) silage treated with PFJ-W; (4) silage treated with PFJ-G; (5) silage treated with PFJ-B; (6) silage treated with PFJ-W; and (7) silage treated with PFJ-G. All the treatments consisted of five replicate silos, and they were prepared in 1·0-L glass jar silos. Results showed that silages treated with fresh and frozen PFJs, regardless of plant material, had better fermentation quality than the control silage in terms of lower pH, butyric acid (BA) and ammonia nitrogen (NH-N) concentrations, as well as higher lactic acid (LA) concentration ( P < 0·05) and in vitro organic matter digestibility (IVOMD), metabolizable energy (ME) content, and gas production values ( P < 0·05). Results indicated that PFJ treatments enhanced the nutritive value, fermentation quality and IVOMD, ME content and gas production values of first-cut lucerne silages. [ABSTRACT FROM AUTHOR]

A greenhouse experiment was conducted to detect the soil residues of metribuzin, imazethapyr and pronamide applied in established alfalfa (Medicago saliva L.) stand by a bioassay using wheat (Triticum vuigare L.). Detection of herbicide residues was determined from soil samples collected from depths of 0-5, 5-10, 10-20 and 20-30 cm. Most of the herbicides did not significantly affect studied parameters: plant density, height and fresh weight of wheat plants/container in any soil depth. Exception was pronamide, which significantly reduced wheat plant density, height and fresh weight of wheat at 10-20 and 20-30 cm depth. [ABSTRACT FROM AUTHOR]

A greenhouse experiment was conducted to detect the soil residues of metribuzin, imazethapyr and pronamide applied in established alfalfa (Medicago sativa L.) stand by a bioassay using wheat (Triticum vulgare L.). Detection of herbicide residues was determined from soil samples collected from depths of 0-5, 5-10, 10-20 and 20-30 cm. Most of the herbicides did not significantly affect studied parameters: plant density, height and fresh weight of wheat plants/container in any soil depth. Exception was pronamide, which significantly reduced wheat plant density, height and fresh weight of wheat at 10-20 and 20-30 cm depth. [ABSTRACT FROM AUTHOR]

Meiss H, Médiène S, Waldhardt R, Caneill J, Bretagnolle V, Reboud X & Munier-Jolain N (2010). Perennial lucerne affects weed community trajectories in grain crop rotations. Weed Research 50, 331–340. Complex crop rotations may be beneficial for weed management. We analysed how pluriannual forage crops may affect weed composition during cereal-based crop rotations. Using a space-for-time-substitution design, we compared weed composition and diversity before, during and after perennial crops. We surveyed four groups of fields: (a) winter wheat ( Triticum aestivum L.) following annual crops, (b) 1-year old lucerne ( Medicago sativa L.) following annual crops, (c) 2–6 years old lucerne and (d) winter wheat following pluriannual lucerne in western France (420 fields in total). Weed composition varied among the four groups, suggesting a cyclic trajectory corresponding to the phases of the crop rotation. Indicator Species Analysis showed that these differences were due to at least 40 species, including the most common weeds. A functional group analysis showed that perennial lucerne crops shifted the communities away from several problematic weeds, especially annual broad-leaved species with an upright or climbing morphology. This effect was also visible in the wheat following lucerne. Other species (including perennials, annuals with rosettes and some grasses) benefited from the particular growth conditions in lucerne but decreased in the following wheat. The diversification of arable crop rotations with perennial crops may thus be useful for Integrated Weed Management, reducing the need for herbicides. Other species less harmful to annual crops were favoured, resulting in increased floristic diversity. [ABSTRACT FROM AUTHOR]

This study aimed to investigate whether sheep offered free-choice intake of forage and concentrate develop subacute ruminal acidosis (SARA) and to identify SARA-associated feeding behavior components. In a crossover design over two 28-d periods, 11 rumen-cannulated wethers received wheat and alfalfa hay in 2 separate compartments. Concentrate and forage were provided for ad libitum access or in a fixed amount corresponding to 80% of ad libitum hay intake with a concentrate:forage ratio of 60:40 on a DM basis. In both diets, sheep were fed 2 equal portions at 0800 and 1600 h. Ruminal pH, voluntary intake, and feeding behavior were recorded continuously from d 1 to 9 and d 15 to 23 in each period. When no measurements were performed, the animals were housed in larger pens with straw bedding. When fed for ad libitum intake, the sheep ingested 1,340 g of DM/d consisting of 49.1% wheat, whereas with the fixed diet they ate 872 g of DM/d consisting of 58.4% wheat. Sheep fed for ad libitum intake spent more time with ruminal pH < 5.6 than when fed in fixed amounts (7.77 vs. 3.05 h/d, P < 0.001). The time spent with ruminal pH <5.6 was mainly linked to the amount of feed ingested and especially the amount of wheat (P < 0.001). Our results suggest that when fed for ad libitum intake with free choice wheat, the achieved concentrate:forage ratio of near 50:50 and a larger hay intake enable sheep to consume more wheat. When sheep were fed for ad libitum intake, feeding bouts were spread evenly throughout the day. Although ruminal pH reached the same minimum level in both diets after main meals, time to reach pH nadir was longer with ad libitum diet (P < 0.001). In addition, after reaching this minimum value, ruminal pH increased more slowly in this diet, inducing a decreased preprandial ruminal pH (P < 0.001). Consequently, the ad libitum diet led to a longer time below pH 5.6. A slow decrease in ruminal pH may enable sheep to consume larger quantities of food. However, free access to concentrate maintains continuously elevated content of ruminal fermentation end products and so requires more time for pH to return to neutral values. Thus, interval between feed distributions should be as large as possible to help resume the preprandial ruminal pH and to limit time spent with pH <5.6. [ABSTRACT FROM AUTHOR]

Abstract: The management of water and nutrients in farming systems that incorporate alternating phases of lucerne pasture with annual grain crops posses additional challenges to rotations with annual crops only. Strategies for balancing water and nutrient resources within and across rotations will be governed by local soil, climatic, skill and economic constraints. On the Loess Plateau in China, farmers have been encouraged to grow lucerne (Medicago sativa) to reduce soil erosion and improve soil fertility on cropping lands but with little supporting information on how to incorporate lucerne within subsistence cropping systems. Lucerne–wheat rotation experiments were established at two locations in Gansu Province and examined the yield of lucerne and wheat along with changes in soil water and nitrogen (N). Lucerne proved to be well adapted to the high water holding capacity soils and summer dominant rainfall environment of the region with annual production of around 12tha−1 at the higher rainfall site (Qingyang). An old (30 years), sparse stand of lucerne growing in the drier location (Dingxi) was much less productive, being dependent on incident rainfall. Apparent water use efficiency (WUE) of lucerne over individual harvest periods ranged from 4 to 56kgha−1 mm−1 at Qingyang. Lucerne was able to dry the soil to the crop lower limit (CLL) to depths of 3m and there was clear evidence that lucerne roots were extracting water below this depth. Wheat following lucerne is subject to low plant available soil water at sowing, unless substantial rainfall occurs, but climate variability in this region makes this difficult to predict. Rain which falls during short fallow periods after lucerne termination provides opportunity for N fertiliser responses, which may be greater after large rainfall events that lead to N leaching. In drier environments such as Dingxi, deep drainage and leaching appear unlikely under rotations which incorporate lucerne, and here evaporative water loss from the soil surface presents a more significant management challenge. The overall variability in seasonal rainfall at both sites, even within the short period of this study, indicates that an adaptive management strategy may be required, rather than fixed rotations. Systems modelling may shed further light on the most useful strategies to manage crop rotations within this variability. [Copyright &y& Elsevier]