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Water footprint (WF), water productivity of wheat (WWP) and interrelationships among water footprint components under conservation (CST) and conventional (CT) tillage were evaluated for two cropping years in this study. Results revealed that WF in CST was lower than that in CT one. While, WWP in CST was higher than that acquired from CT. The total, green, blue and gray WF in conservation (vs. conventional) tillage averaged 1319 (vs. 1629), 108 (vs. 152), 621 (vs. 737) and 590 (vs. 740) m3 t−1. The gray WF had the highest total and direct effects on total WF. Also, higher grain yield (3857 kg ha−1), straw yield (5065 kg ha−1) and WWP (1.01 kg m−3) acquired from CST. The findings revealed that CST is the appropriate tillage practice to reduce total WF (19%) compared to CT, to enhance crop yield and productivity in wheat production. [ABSTRACT FROM AUTHOR]

Nitrous oxide (N2O) emission is mainly associated with aerobic crop culture, which is influenced by nitrogen (N) fertilizer sources, rates, placement methods, and water management systems. The influence of N fertilizers on greenhouse gas (GHG) emission patterns are not well documented in Asian region. The present investigation was undertaken to identify GHG emission patterns, net carbon budget, net global warming potential (GWP) and GHG intensity. N fertilizer from prilled urea (PU), urea super granule (USG) and N-phosphorus (P)-potassium (K) briquette (NPKB) were used and compared with control (no fertilizer). Equal nutrient doses were maintained for all the treatments irrespective of fertilizer sources. Static close chamber technique was used for measuring GHG emission. Depending on treatments, total methane (CH4), nitrous oxide and carbon dioxide (CO2) fluxes were 8.16–10.85, 0.57-0.49-0.59 and 1739–2309 kg ha−1 season−1, respectively and net GWPs varied from −1292 to −2438 kg CO2 eq. ha−1 season−1. Wheat grain yields significantly varied from 3.2 to 3.9 t ha−1 because of N sources and rates. Use of USG for wheat cultivation can increase CO2 removal about 22–88% from the atmosphere along with about 2–14% grain yield and 26–48% soil organic carbon (SOC) sequestration improvements compared to other N sources in Bangladesh. [ABSTRACT FROM AUTHOR]

Bread is one of the most important processed foods of wheat flour worldwide. Breadmaking quality is determined by grain protein content and its composition and is highly influenced by fertilization management. This study investigated the effects of spraying different combinations of exogenous regulators on breadmaking quality of the flour. Three spraying schemes including Potassium glutamate+Zinc+Urea (G), Methionine+ Zinc+Urea (M), Cysteine+ Zinc+Urea (C) were screened out to improve the yield and total protein contents in the flour. In addition to protein, the amounts of gliadin, glutenin, glutenin subunits, and gluten were elevated in the treatments listed above. Exogenous regulators, on the other hand, increased bread volume by 14% to 17%. In comparison to G and C, M treatment more efficiently increased the protein quality of inner endosperm rather than aleurone, resulting in superior gluten quality and breadmaking quality of the flour. Our results provide an optimizing combination for improving the quality of bread wheat and demonstrate the varied modulations of exogenous regulators on the spatial distribution of protein in wheat grain. [ABSTRACT FROM AUTHOR]

Poly-γ-glutamic acid (γ-PGA) is an environment-friendly super absorbent polymer that can be used as a soil conditioner, which is promising to improve crop productivity and cope with soil degradation. The objectives of this study are to study the effects of γ-PGA on soil physicochemical properties and winter wheat (Triticum aestivum L. cv. Xinong 975) production in arid region of Northwest China. According to the mass ratio of γ-PGA and soil, experiment treatments consisted of four different γ-PGA application rates, which were designated as 0 (CK), 0.05% (P0.05), 0.1% (P0.1), and 0.15% (P0.15), respectively. The mixed soil samples were uniformly filled into identical plastic pots. Each treatment had three replicates randomly distributed within 12 pots. The results indicated that γ-PGA significantly increased saturated water content by 6.3-11.5%, field capacity by 8.4-15.3%, and plant available water by 5.1-12.5% compared with the CK. γ-PGA increased soil NO3−-N content and residue, and enhanced the proportions of soil macro-aggregates compared with the CK. γ-PGA increased winter wheat yield by 29.3-34.7%, and WUE by 21.2-33.3% compared with the CK. The main conclusion γ-PGA application amount of 0.05-0.1% can be used to improve soil physicochemical properties and winter wheat production in degraded soil. [ABSTRACT FROM AUTHOR]

Rice straw (RS), biochar (BC) and lime (LM) have proved to be effective immobilizing agents in acidic contaminated soil. Up-to-date scientific data is lacking regarding residual effects of these amendments in acidic soils and wheat/rice cropping system. The objective was to analyze the efficacy of amendments to improve grain yields, nutritional quality, and reduce Ni bioavailability of wheat/rice rotation system. A pot experiment was conducted to examine the efficacy of RS, BC 10 and 20 g kg−1 and LM 10 g kg−1 application rates on plant growth, nutritional quality and Ni contents in wheat and rice tissues and grain. Amendments enhanced Ni immobilization, declined their uptake by plants and accumulation in the grains of both crops. Rice straw biochar reduced several factors like health risk assessment, Ni uptake and bioconcentration factor. BC 20 g kg−1 increased shoot, root and grain yields, while enhanced essential nutrients in the wheat/rice cropping system compared to untreated soil. Soil amendments significantly decreased toxicity characteristics leaching procedure (TCLP) extractable Ni by 42.25% and 42.62% and simple bioaccessibility extraction test (SBET) by 42.1% and 45.25% in post- wheat/rice crops. This process enhanced the safety of wheat/rice rotation cropping system to be consumed and mitigated security risks. [ABSTRACT FROM AUTHOR]

Water and energy crisis, rising temperature and subsequent changes in climate result in calamitous loss of wheat productivity due to adverse effect on plant growth and development. Plateauing yield trends and declining total factor productivity compel for alternative water and energy-efficient conservation practices supporting sustainable wheat productivity in humid tropics. Present investigation tested the hypothesis stating that the alternate wheat establishment methods and inter-culture practices would economize energy and water requirement with enhanced productivity. Different wheat establishment methods viz., conventional tillage, reduced tillage, zero tillage and raised bed landforms of 40/20 and 60/20 cm and two inter-culture practices, i.e. conoweeding and alternate ridging on spring wheat were evaluated for two years at Pantnagar in Uttarakhand, India. Zero and reduced tillage depicted better economic viability with benefit cost ratio of 2.86 and 2.84, respectively, which was statistically at par with conventional tillage. Alternate ridging and raised bed (60/20 cm) recorded 13.3 and 41.7% saving of irrigation water, respectively. Highest energy use efficiency was observed in raised bed 60/20 cm with 22.4% less energy consumption compared to conventional method. Thus, adoption of conservation practices with improved inter-culture operations holds potential for sustainable, water and energy-efficient and profitable wheat productivity. [ABSTRACT FROM AUTHOR]

One of the practices which could mitigate the negative effects of drought stress is ammonium nutrition. Nitrification inhibitor (DMPP) can keep ammonium concentrations high in the soil for several weeks. Although there are contradictory reports regarding the priority of NH4+ uptake and its toxicity effects on wheat, it is necessary to understand better how to apply DMPP to increase drought tolerance without any negative effects. The field experiment was conducted using 15N trace technology. The fertilizers treatment included (15NH4)2SO4 and (15NH4)2SO4 with DMPP at four drought stress levels. Available soil mineral nitrogen was measured, as well as yield components and 15N recovery. The results showed that DMPP application at full irrigation and moderate drought stress caused an increase in grain yield of 13% and 10%, respectively. DMPP application at full irrigation, moderate and severe drought stress caused a significant increase in nitrogen use efficiency of 19%, 11%, and 17%, respectively. It seems DMPP application at the stem elongation stage, promoted NH4+ assimilation and transfer to the shoots, which has created relative resistance to drought stress conditions. In conclusion, it is recommended that farmers use DMPP at stem elongation to avoid wheat yield reduction and nitrogen recovery under drought stress. [ABSTRACT FROM AUTHOR]

Heat stress during the grain filling is one of most critical factors impacting grain yield in winter wheat. In a two-year field experiment, we studied the effects of 24-Epicastasterone and KH2PO4 on heat-stressed wheat applied during different times. A completely randomized block design was used with three reagents, that is, 24-Epicastasterone, KH2PO4 and H2O and three spraying times, that is, pre-heat, under-heat and post-heat. Two cultivars, that is, Huaimai 33 and Annong 0711 were subjected to a 7 d post-flowering heat stress using plastic tents. Our study suggests that greater grain weight in heat-stressed plants was achieved through sustaining leaf greenness and higher assimilates supplies to grains. When heat-stressed plants sprayed either with 24-Epicastasterone or KH2PO4 could sustain a relatively higher leaf photosynthetic capacity by up-regulating antioxidant enzymes with reduced damage on lipid membranes and leaf chlorophyll. We also found that KH2PO4 was relatively more effective in improving leaf physiology and grain yield of heat-stressed plants than 24-Epicastasterone. Further analysis showed that pre-heat or post-heat was more pronounced in protecting plants from heat injury than spraying the plants under heat stress. Thus, spraying KH2PO4 either prior to or post stress incidence is recommended to protect wheat crops from terminal heat stress. [ABSTRACT FROM AUTHOR]

Long-term, excessive application of synthetic N fertilizers will reduce soil aggregate stability and N supply capacity in corn–wheat (Zea mays L. – Triticum aestivum L.) rotation. This study aimed to determine the effects of soybean (Glycine max L.) on soil aggregation, soil organic N (SON) and net amount of N mineralization (NANM) in wheat season compared with corn. Three rotation systems, corn–wheat (C-W), soybean–wheat (S-W) and soybean inoculated with Rhizobium-wheat (SR-W) were established in 2017. In wet screening, compared with C-W rotation, the mass proportions of large macro-aggregates (LM%) + small macro-aggregates (SM%) at 0–20 cm was increased by 51.9% and 16.6% under S-W and SR-W rotations, respectively, and was increased by 50.6% and 59.8%, respectively, in the 20–40 cm. The proportions of LM + SM-associated N (LMN% + SMN%), ammonium N (AN) and amino acid N (AAN) were higher under the S-W and SR-W rotations. Furthermore, the NANM of S-W and SR-W rotations increased by 34.1% and 28.6% compared with C-W rotation, respectively, and the non-N benefits of soybean played an important role. In conclusion, the improvement degree of soil aggregation by soybean is an important factor affecting soil N mineralization in wheat season. [ABSTRACT FROM AUTHOR]

Grain yield and protein concentration are critical traits determining wheat economic value and are dependent on nitrogen (N) supply and crop N status. However, application of N fertilisers is costly and has a large environmental footprint. We assessed the effect of slow-release rock mineral fertiliser (RMF) with or without microbial consortium inoculant (MI) on growth, grain yield and protein content of winter wheat grown in a low-fertility soil. The experiment was set up with three factors [RMF rates (0, 10 and 20 mg N kg−1 soil), MI (with and without) and two wheat genotypes] replicated four times and harvested twice (anthesis and maturity). The addition of MI increased root biomass at anthesis, but there was no effect at maturity. The shoot and grain nutrient content and protein yield were highest in plants treated with 20 mg N kg−1 soil. The plants treated with MI resulted in lower grain protein concentration than without MI. Arbuscular mycorrhizal (AM) colonisation was higher in treatment with than without MI. The application of RMF at 20 mg N kg−1 soil produced higher plant growth, nutrient content, grain and protein yield compared to control in nutrient-poor sandy soil. [ABSTRACT FROM AUTHOR]

Nitrogen (N), the most vital nutrient, undergoes a transformation in the soil and was subjected to loss through ammonia volatilization, nitrate leaching, and denitrification, which lower the soil fertility, crop yield and pollute the environment. Integrated nutrient management (INM) improves the nutrient supply system by integrating recommended dose fertilizers and biofertilizers, lessens the nitrogen losses, and synchronizes with the nutrient demand of the crop. To evaluate the impact of INM on minimization of N losses and improvement of wheat (Triticum aestivum L.) yield and growth parameters, a field experiment was conducted with different combinations of biofertilizers along with the recommended dosage of fertilizers. Application of NPK + Azotobacter + mycorrhiza (Tram) in combination was found to improve soil nitrogen dynamics, availability of P, K, microbial activity, root growth, urease activity, and nitrogen use efficiency as compared to NPK (Tr) only. The cumulative emission from ammonia flux in the INM plot varied from 10.2 to 10.6 kg ha−1 and denitrification losses varied from 2.4 to 2.5 kg ha−1. At the same time, these were recorded significantly higher in Tr plot. The yield obtained under the INM plot receiving Tram was recorded as 6.4 t ha−1, which is higher than other treatments. [ABSTRACT FROM AUTHOR]

Bacteria are among the most frequently studied microorganisms in plant growth-promoting traits and fighting against different pathogens. Actinobacteria are prokaryotic organisms that produce mycelium, spores, and can form various secondary metabolites, especially antibiotics. In our study, free-living and endophytic Actinobacteria were isolated from rhizosphere soils and plant parts of olive (Olea europaea L.) and walnut (Juglans regia L.) trees, which are commercially essential agricultural products for Turkey. The study aimed to explore the plant growth-promoting activities of these Actinobacteria as biological fertilizers. Some of the properties of purified Actinobacteria that regulate the plant growth-promoting (PGP) traits; phosphate solubilization, indole-3-acetic acid, siderophore, ammonia, protease, beta-galactosidase, chitinase production, and antagonistic activities against various plant-pathogen fungi were investigated. As a result, 422 Actinobacteria were isolated, and 88 Actinobacteria determined to be possible plant bio-fertilizers were identified as Streptomyces spp. (70), Amycolatopsis spp. (12), Micromonospora spp. (four) and Nocardiopsis spp. (two) after the sequencing of their 16S rRNA genes. Moreover, four Streptomyces spp. and two Amycolatopsis spp. were used in hydroponic germination of wheat seeds (Triticum aestivum L.), and plant growth in terms of root and stem parts increased. [ABSTRACT FROM AUTHOR]

Eight integrated crop management (ICM) practices were evaluated for six years consecutively, which are ICM1&2: 'business-as-usual' (conventional transplanted rice fb flatbed wheat), ICM3&4: conventional direct seeded rice (DSR) fb furrow irrigated raised-bed wheat without residues, ICM5&6: conservation agriculture (CA)-based zero-tilled (ZT) DSR fb ZT wheat with the wheat and rice residues and ICM7&8: CA-based ZTDSR fb ZT wheat with the wheat, mungbean and rice residues. ICM7-8 produced 9.6–16.4% and 9.4–9.9% greater system rice equivalent yield (REY) than the ICM1-4 and ICM5-6, respectively. Residue-retained CA-based ICM5-8 had 23.2% and 58.5% greater N and P balance, respectively, than the residue removed (ICM1-4); subsequently, negative K balance (–53 to –115.5 kg ha−1) was recorded in ICM1-4. ICM5-8 consumed ~60-78% of total energy and produced the highest energy output (Eo) in rice (11.5–12.6%)/wheat (7.3–13%) than ICM1-4. In contrast, ICM1-4 had a greater energy use efficiency (EUE) compared to ICM5-8 due to lesser energy input (EI) through indirect renewable sources. At a soil depth of 0.0–0.45 m, the ICM5-8 contributed 7.9% and 20.2% greater active and passive OC pools over the ICM1-4. Thus, CA-based ICM in rice-wheat rotation (RWR) could be a possible substitute for the positive nutrient balance, system yields and energy and carbon dynamics. [ABSTRACT FROM AUTHOR]

Organic amendments could improve soil nitrogen (N) availability and transformation characteristics, which decreases the N loss within soil profile induced by N excessive application. A field experiment was designed in Shiqiang village with different organic amendments in 2018: (i) control (CK); (ii) chemical fertilizer (NPK); (iii) 1200 kg C ha−1 plus NPK (NPKM) and (iv) 40 kg humic acid ha−1 plus NPK (NPKH). Compared with NPK treatment, in 0–30 cm soil, NH4+-N content in NPKM and NPKH treatments was increased by 9.15% and 13.36% and NO3– N content was increased by 11.44% and 12.85%, respectively, while in 30–60 cm soil, NO3– N content in NPKM and NPKH treatments was decreased by 13.51% and 8.54%, because organic amendments inhibited N leaching to deeper soil. Soil urease and invertase activity in NPKH treatment was 9.52% and 8.31% higher than that in NPK treatment, which was decreased with the decreasing soil depth. The grain yield was increased by 14.17% and 23.87% in NPKM and NPKH treatments, respectively. Thus, humic acid fertilizer was better in increasing wheat yield by improving N transformation and enzyme activities, which could increase wheat N uptake and inhibit N loss in North China Plain. [ABSTRACT FROM AUTHOR]

In recent years, the sustainability of the rice-wheat cropping system in Indo-Gangetic Plains is facing many problems in various fronts viz., agricultural, ecological, environmental and economical. Therefore, to ensure long-term sustainability, the rice-wheat cropping system needs to be diversified. The present study was conducted to identify an alternative cropping system for Indo-Gangetic Plains region of India by diversifying and intensifying the current rice-wheat cropping system. Ten treatments (rice-wheat = control, rice-wheat-green gram, rice-potato-green gram, rice-wheat-cowpea fodder, rice-potato-cowpea fodder, rice-berseem fodder-maize fodder, rice-berseem fodder-cowpea fodder, rice-mustard-sudan grass fodder, rice-mustard-cowpea fodder and rice-cabbage-cowpea fodder) were compared consecutively two years in randomized block design with three replications. Diversification of rice-wheat cropping system with rice-potato-green gram resulted in increase in system productivity (142.35%), gross returns (99.57%), net returns (130.34%), profitability (130.96%), relative production efficiency (142.53%), relative economic efficiency (130.79%) and labour employment (55.73%). The inclusion of legume crops in cropping sequences was found better in improving the soil quality parameters. Our results revealed the significance of diversification and intensification of rice-wheat cropping system under irrigated ecosystem of IGP as it enhanced system productivity, profitability and soil health. [ABSTRACT FROM AUTHOR]

Crop rotations and residue management contribute to the sustainability of the soil and environment and reduction of fertiliser use. However, appropriate crop and residue level combinations have yet to be determined to maximise productivity, while ensuring the preservation of soil resources in different agricultural production systems. The experiment evaluated production and soil chemical properties in bean after three preceding crops (bread wheat, durum wheat, and corn) with four residue incorporation levels (0%, 50%, 100%, and 200%) under irrigation conditions in volcanic soil in south-central Chile. A split plot design with four replicates was used. Results indicated that the production of grain and crop residue of bean were higher after corn and durum wheat. The preceding crop also affected some soil chemical properties, especially after the corn crop. The production parameters were not affected by the different residue levels; these had a positive effect on the concentrations of N, K, and Mg and an effect that was directly proportional to the residue level being used. Correlations between soil chemical properties were also established, consistently highlighting the increase in the concentration of the nutrients N, K, Ca, and Mg associated with increases in organic matter content. [ABSTRACT FROM AUTHOR]

A long-term experiment was initiated in a sub-humid tropical Indian rice-wheat system to identify suitable soil quality indicators for determining yield and sustainability of the system as influenced by chemical fertilizers (NPK) alone or in combination with organic amendments viz. farmyard manure (FYM), paddy straw (PS) and green manure (GM). Soil samples were analysed for physical, chemical and biological indicators after 30 crop cycles and the soil quality index (SQI) was calculated by nonlinear scoring functions following the methodology of principal component analysis and multiple regression analysis-based minimum data set selection. Application of NPK fertilizers in combination with FYM and GM significantly increased systems yield and sustainability (sustainable yield index or SYI) as well as improved soil properties compared to the control and other combinations. The value of the dimensionless SQI varied from 2.0 in the control plot to 3.1 in the NPK+FYM. A greater SYI and SQI in the NPK+FYM treatment suggested that FYM in combination with chemical fertilizers has an edge over GM and PS. Among all the indicators (30) under study, available-N, soil organic carbon, available-B and aryl-sulfatase were screened as suitable indicators which contributed 24, 29, 24, 22%, respectively to the SQI in NPK+FYM treatment. [ABSTRACT FROM AUTHOR]

Soil microbial processes can serve as sensitive indicators of soil quality. A 2-year field experiment was conducted to determine the combined effects of tillage (conventional, CT; reduced, RT; and no tillage, NT) and residue (with or without residue removal) on soil microbial and enzyme activities under wheat (Triticum aestivum L.)- and corn (Zea mays L.) in a rotation, using a split-plot design with three replications near Shiraz, Iran. The highest microbial biomass (660.19 and 667.00 µg MBC g−1 soil in wheat and corn, respectively) was recorded under RT. Soil respiration was affected by tillage in order NT > RT > CT. The lowest microbial quotient (qCO2) was obtained under RT (15.60 in wheat and 5.94 in corn, respectively), while NT and CT either showed similar effects or NT was superior over CT. The highest acid phosphatase enzyme was obtained under RT (442.65 and 374.17 µg PNP g−1 soil h−1 in wheat and corn, respectively). Alkaline phosphatase and urease enzymes were highest under NT. Our research has shown that replacing CT with conservation tillage (especially RT) can greatly improve soil enzymes and microbial biomass and optimize qCO2 values under wheat- and corn in a rotation in a short term. [ABSTRACT FROM AUTHOR]

Soil erosion and drought are significant environmental hazards for crop production in the northwestern coastal zone of Egypt, leading to increased soil resources degradation. In-situ rainwater harvesting techniques by changing the micro-topography of soil via tillage practices can increase runoff retention and improve soil productivity. In this study, field trials were conducted on a sandy loam soil to determine the effects of four tillage systems [integrated ridge-furrow tillage (RFT), integrated reservoir tillage (RT), conventional tillage (CT), and No tillage (NT)] on soil bulk density, volumetric water content, runoff, soil loss, precipitation use efficiency, and winter wheat yield during two growing seasons under-rainfed conditions. The results indicated that tillage systems significantly affected soil properties, precipitation use efficiency and wheat yield in the order of: RFT > RT > CT > NT. Compared with the CT, the mean runoff with the developed RFT and RT was significantly decreased by 55.4% and 40.3%, respectively. Meanwhile, the precipitation use efficiency increased by 18.1% and 9.5%, respectively. By taking into account the stability of soil productivity along with environmental protection, it is suggested that the RFT and RT are the tillage systems that can efficiently increase the availability of soil water and, consequently, wheat yield. [ABSTRACT FROM AUTHOR]

Wheat cultivation under a dual-purpose (DP) system holds great potential to provide additional fodder for livestock with marginal grain reduction. This study explores the potential of wheat as a DP crop for improving both, forage and grain cropping system by finding out optimal sowing dates and cultivars suitable for DP cropping. Field experiments with four cultivars (Saleem-2000, Bathoor-2007, Fakhre Sarhad-99 (FS-99) and Siran-2008), three sowing dates (October 15, October 30 and November 15) and two cutting treatments (cut and no-cut) determines the effects on yield and physiology of wheat. Wheat sown either in mid or end of October resulted in 11 and 8% increase in grain yield while 13 and 9% in biological yield over mid November sowing, respectively. This increase in yield was due to higher grain spike−1, chlorophyll content, transpiration rate and relative water content. The cultivars Siran-2008 and Saleem-2000 had higher biological and grain yields than other cultivars across cutting and sowing dates treatments. Biological and grain yields were reduced by 4% and 3%, respectively under the DP wheat compared with no-cut treatment, but grains N content was unaffected. Conclusively, DP wheat system (cut treatment) had higher profitability (11.2%) than wheat crop sown only for grain purposes. [ABSTRACT FROM AUTHOR]

A field experiment was conducted in years 2016–2018 in crop-rotation: faba bean-winter wheat-winter wheat. After seedling emergency (2016) mineral fertilizer (15NH4)2SO4 having 20.1 at% 15N (dose of 30 kg N ha−1) was applied. The faba bean biomass contained 194.1 kg ha−1of nitrogen (140.0 kg of N in seeds and 54.1 kg in crop residue). This amount included 58.7 kg N ha−1 in seeds and 21.2 kg of N in crop residuesthat were fixed from the air. Crop residue were ploughed into soil. Plots with winter wheat cultivated after faba bean (2017) were divided on two sub-plots 0 and 100 kg N ha−1. Overall, winter wheat cultivated for two subsequent years took up from total nitrogen of crop residue 16.1 kg ha−1 of N in control and 29.8 kg ha−1 in fertilized plots, but from biologically fixed nitrogen 6.29 and 11.6 kg ha−1, respectively. Applied fertilizer contained 5.920 kg 15N ha−1 from which 1.577 kg 15N ha−1 was cumulated in faba bean seeds, 0.662 kg 15N ha−1 in crop residue (sum 2.239 kg 15N ha−1), 0.195 kg 15N ha−1 and in winter wheat harvested (2017) and 0.084 kg 15N ha−1 in winter wheat harvested (2018). [ABSTRACT FROM AUTHOR]

Studies on subsequent effects of Cu pollution on mineral nutrients uptake in different tissues of crops grown in sierozem are limited. A pot experiment was conducted to reveal the effects of exogenous Cu on the accumulation and translocation of Cu and the interaction with nutrients in different tissues of wheat in Cu-polluted sierozem in northwest China. Results showed that the average concentration of Cu in different tissues of wheat was roots > stems and leaves > grains > shells. The bioaccumulation factor (BCF) of Cu in different parts of wheat was roots > stems and leaves > grains > shells. There was a weak translocation of Cu from sierozem to tops of wheat. Furthermore, the translocation ability of Cu from roots to tops of wheat was increasingly weak with increasing Cu stresses. Micronutrients (Fe, Mn and Ca) distribution in different wheat tissues indicated that uptake and upward translocation of these kinds of micronutrients could be affected by high soil Cu concentration. The addition of Cu in sierozem promoted the Mn absorption in wheat tissues, which may also be helpful to solve the lack of Mn in wheat caused by the Cu shortage in sierozem. [ABSTRACT FROM AUTHOR]

The experiment was conducted to appraise whether exogenously applied selenium (Se) could alter nutrients acquisition and metabolism to mitigate the toxic effects of salinity in wheat. Seeds of two contrasting wheat (Triticum aestivum L.) cultivars (Auqab-2000 and Seher-2006) were pre-treated with different concentrations (0, 50, 100 µM) of sodium selenate for 12 h. The pots were irrigated with different NaCl concentrations (0 and 150 mM) applied through Hoagland's nutrient solution before sowing. Salinity reduced fresh and dry mass and grain yield, but the exogenous Se restored the growth and increased grain yield. Further, salt stress decreased the concentrations of K+, Ca2+, P, N, Fe and Se while increased the concentration of Na+ and Cl‒ in the shoots and roots of wheat. The exogenous Se increased K+, Ca2+, N, Fe and Se concentrations while decreased Na+, Cl− and P, and thus mainly reversed the inhibitory effects of salinity on nutrients uptake. Further, exogenous Se increased the accumulation of proline and glycinebetaine under salinity. Overall, Se-priming proved an effective shotgun technique to mitigate the detrimental effects of salinity possibly through its beneficial effects on tissue-specific ion acquisition and accumulation of osmoprotectants in wheat. [ABSTRACT FROM AUTHOR]

In scarce-irrigated areas of India, pearl millet-wheat cropping system is depleting soil quality, system productivity and resources. The objective of study was to restore soil quality and sustain productivity. It was considered necessary to diversify cereal through legume-based wheat system and shift of traditional to conservation technologies. A field experiment was assessed the rainy season cereal crop pearl millet (PM) and three legumes- pigeon pea (PP), green gram (GG) and cluster bean (CB)-based winter wheat (W) systems under two land levelling methods viz. traditional (TLL) and precision laser assisted (PLL), and three establishment methods- traditional tillage (TT), zero tillage (ZT) and permanent broad bed- furrow (PBBF) on various parameters. Results of PLL and PBBF crop establishment was significantly enhanced the soil quality parameters, growth characters, less plant mortality of rainy season crops and lodging of wheat compared with traditional practices. Overall improvement in soil quality, system- and water productivity (WP) and net returns were in ordered: PP-W > CB-W > GG-W > PM-W and PBBF > ZT > TT. Results indicated that PBBF crop establishment in PLL conditions can be made more sustainable productive, economic profitable, ameliorate soil quality and save resources in scarce/canal support irrigation system. [ABSTRACT FROM AUTHOR]

Three-year multi-location field experiments were conducted in soils of varying inherent nitrogen (N) supply in diverse agro-climatic zones for improving productivity and mitigating N2O emissions in timely sown and late sown wheat. The biomass, total N uptake (TNU) and spectral properties were monitored at different growth stages. Biomass production and TNU statistics of only 0.76% and 3.4%, respectively, till Zadoks 14 growth stage (four leaves stage) revealed that applying all fertilizer N dose by Zadoks 14 is not an appropriate strategy to assure fertilizer N supply throughout the growth stages. Rescheduled fertilizer N topdressings with moderate N (25 kg ha−1) at sowing and remaining N dose in two equal splits at Zadoks 14 and Zadoks 29 (main shoot and 9 more tillers) growth stages reduced N2O and GHG emissions, respectively, by 32.4% and 30.6%. Sustained N supply till grain filling produced an average of 5.1% to 10.5% higher grain yield and 2.1% to 10.5% higher grain protein content. The spectral properties recorded with PAU-LCC and SPAD meter at Zadoks 29 growth stage governed the grain yield response to fertilizer N application and can be used to fine-tune fertilizer N topdressing decisions over a wide range of varieties, locations, sowing timings and environments. [ABSTRACT FROM AUTHOR]

Zinc (Zn) deficiency is prevalent in human populations in developing countries. The present study compared two wheat (Triticum aestivum L.) cultivars [Jauhar-2016 (standard wheat) and Zincol-2016 (Zn-biofortified wheat)] for Zn biofortification with optimum soil Zn application. For this, Zn (at 0, 3, 6, 12 and 24 mg Zn kg−1) was applied to pots having an alkaline calcareous soil. Grain yield, grain Zn concentration and grain Zn bioavailability in both cultivars were significantly increased by Zn fertilization. However, Zn application decreased iron (Fe) and phytate concentration in grains of both cultivars. As compared to Jauhar-2016, Zincol-2016 had significantly higher grain Zn concentration and grain Zn bioavailability at all the respective soil Zn rates excepting only at control. At 6 mg Zn kg−1, Zincol-2016 attained in grains a desired concentration of Zn (53 mg Zn kg−1) and a desired level of human Zn bioavailability (2.8 mg d−1 for women and was 3.0 mg d−1 for men). Jauhar-2016 also attained such comparative levels but only at a plant toxic rate of Zn (24 mg Zn kg−1). Conclusively, soil Zn application (agronomic biofortification) to Zn-biofortified wheat (Zincol-2016) may be a promising approach to decrease human Zn deficiency in population groups dependent on wheat-based diets. [ABSTRACT FROM AUTHOR]

In this two-year field study, influence of seed size on the growth and performance of wheat sown under different sowing methods was evaluated. The experiment comprised of three seed size classes viz. bold size, medium size and small size and five sowing methods, (1) broadcast, (2) line sowing, (3) no-till sowing, (4) bed planting, and (5) broadcast augmented with furrows. Among sowing methods highest yield (4.59 and 4.40 t ha−1) and water productivity (2.02 and 1.92 kg m−3) were recorded in bed planting. During both years, yield of bed planted wheat was significantly higher (5–29%) compared with other sowing methods. However, less cost of production in no-till sowing resulted in higher resource use efficiency (0.91, 0.73) than other wheat planting methods. Among seed size classes, the crop raised from bold seeds performed better for weed competitiveness, nutrient uptake, and resource use efficiency (0.79 and 0.63). The yield of crop raised from bold seeds was the best in all sowing methods except in broadcast where medium sized seeds performed better for yield (4.19, 4.35 t ha−1), nutrient uptake and resource use efficiency (0.73, 0.63). Therefore, planting bold wheat seeds on beds may help harvest better productivity and profitability. [ABSTRACT FROM AUTHOR]

A field experiment was performed to assess the carbon footprint (CF) of four cropping systems to identify the sustainable cropping system. The four cropping systems were cotton monoculture (CM), winter wheat intercropped with cotton (WIC), wheat cropping followed by transplanted cotton (WTC) and direct-seeded cotton after winter wheat harvest (WDC). The CF calculated per unit area (CFa), yield (CFy), biomass (CFb) and economic output (CFe) increased in the order CM < WIC < WTC < WDC in the low-fertility plot and WIC < WTC < WDC < CM in the high-fertility plot. The results indicated that CM was the best cropping system in the low-fertility plot and presented CFa, CFy, CFb and CFe values of 4848.14 kg CO2eq ha−1 a−1, 0.41 kg CO2eq kg−1 a−1, 0.17 kg CO2eq kg−1 a−1 and 0.06 kg CO2eq ¥ a−1, respectively, whereas WIC was the cropping system with the lowest CFs in the high-fertility plot and presented CFa, CFy, CFb and CFe values of 14,410.70 kg CO2eq ha−1 a−1, 1.31 kg CO2eq kg−1a−1, 0.53 kg CO2eq kg−1 a−1 and 0.34 kg CO2eq ¥−1a−1, respectively. Thus, it can be concluded that improving cropping systems provides a good option for reducing CF and consequently mitigating climate change. Abbreviations: GHG: greenhouse gas; LCA: life cycle assessment; CF: carbon footprint; CFa: The CF calculated per unit area; CFy: The CF calculated per yield; CFb: The CF calculated biomass; CFe: The CF calculated per unit economic output; CM: cotton monoculture cropping system; WIC: wheat intercropped with cotton cropping; WTC: wheat cropping followed by transplanted cotton; WDC: direct-seeded cotton after wheat cropping; IPCC: Intergovernmental Panel on Climate Change; CO2eq: CO2 equivalent; SOC: soil organic carbon; PAS: publicly available specification [ABSTRACT FROM AUTHOR]

Quantification of the recovery efficiency of applied N (REN) is essential for optimal N management in croplands. Our specific objectives were to test the feasibility of several new substitution methods for evaluating REN and to find an optimal method for evaluating REN for long-term crop rotations. The ratio method (RM), the soil N balance method (SNBM), and the traditional subtraction method (SM) were used to evaluate crop N utilization in a 7-year positioning wheat-maize rotation experiment. The SNBM obtained the highest value of cumulative REN (61.8–119.7%), followed by the RM (45.2–74.5%), and then by the SM (30.0–53.6%), under the annual N rates of 165–495 kg N ha−1. The inter-annual variation in cumulative REN, as indicated by the coefficient of variation, was lower in SNBM (11.8–17.2%) and RM (12.2–19.6%) than in SM (27.2–35.1%). Both SM and RM based cumulative REN were negatively correlated with annual N rate, but not for SNBM-based REN. The SNBM-based REN was more sensitive to the change of crop yield and apparent N loss than the other two methods. The SNBM-based cumulative REN could be a promising method for evaluating crop N use due to its theoretical orientation for a sustainable soil N supply. [ABSTRACT FROM AUTHOR]

Amino acids are important components of the soil organic nitrogen pool. There is, however, a current lack of knowledge concerning how exogenous C and N regulate amino acid uptake in the soil microorganism/plant system. We used a 13C,15N-glycine injection method to examine glycine-derived 13C and 15N partitioning in a planted or unplanted spring wheat pot experiment. Four treatments were used: control (CK), ammonium sulfate (N), glucose (C), and ammonium sulfate with glucose (NC). The results showed that amino acids were absorbed intact by soil microorganisms and plants at 4 h. An exogenous excess of C, rather than N, resulted in a reduced uptake of intact glycine by soil microorganisms, indicating that glycine was taken up primarily to fulfill their C requirement. Wheat was more effective in competing for glycine-C and N at 24 h. 13C and 15N partitioning in wheat was significantly influenced by exogenous C and N availability; uptake of 13C and 15N by wheat increased with increasing C and N availability. We concluded that amino acids are important not only for N but also for C to soil microorganisms and plants, which are able to respond quickly to exogenous C and N source application. [ABSTRACT FROM AUTHOR]

Rice–wheat (RW) cropping system in India is a major source of N2O emissions. In such system, defining N rates that deliver minimal N2O emissions and economically optimum yield would benefit both food production and the environment. We measured yield and N2O fluxes from RW systems in Northwest IGP under two tillage systems and five N rates (0, 75, 150, 225 and 300 kg N ha−1) for both rice and wheat using static chamber method. Seasonal pattern of N2O emission was mainly influenced by fertilizer and water application events with no significant effect of tillage systems. Mean annual N2O emission from RW system was 1.49 kg N ha−1 in N75 plot and 2.97–3.04 in the plots receiving ≥150 kg N ha−1. On average, the yield-scaled N2O emissions of rice and wheat were 0.25 and 0.52 kg N2O–N mg−1, respectively. Our finding suggests that N rates between 120–200 kg N ha−1 in rice and 50–185 kg ha−1 in wheat provide the most economical returns and application rates beyond these ranges would be both economically and environmentally unsustainable. Within the range of N rate studied, fertilizer-induced N2O-EF for rice and wheat were 0.41% and 0.79%, respectively. [ABSTRACT FROM AUTHOR]

Cadmium happens to interfere with chlorophyll synthesis, calvin cycle and phosphate pathway and the resulting changes in biochemical attributes induce disorders in physiology, biochemistry and genetics of the germinating plants. Its hazardous effects disturb the phenolic contents, sugars, soluble proteins and activities of antioxidant enzymes. We employed mercapto-triazoles as wheat seed priming agents and evaluated their potential to alleviate the negative impact of cadmium stress (5 µM) on biochemical attributes in germinating seedlings. For priming, 10, 20, 30 and 40 mg L−1 solution of each triazolic compound was used and the germination was carried out under normal and Cd stress conditions. Biochemical attributes including sugars, protein contents, total phenolic, total oxidant status, hydrolytic enzymes and antioxidant enzymes were studied under both conditions and compared with control. Almost all triazolic-priming significantly alleviated the deleterious impacts of cadmium and improved protein contents, SOD, POD, and esterase activities with a significant reduction in MDA contents. The decrease in MDA along with the increase in above-said biochemical attributes in wheat seedlings suggests the mitigating effects of tested triazoles against cadmium stress. [ABSTRACT FROM AUTHOR]

Digestate represents an alternative source of nutrients for crops in sustainable agriculture. We aimed to evaluate the effects of digestate fertilization on grain (GY) and straw yield (SY) and nutrient content and uptake in winter wheat (WW) and spring barley (SB). The study duration was from 2012 to 2016, with the following crop rotation: WW/WW/SB/WW. Every year, the same fertilizers were applied to each respective plot: control, digestate, digestate + straw, cattle slurry and mineral NPK fertilizer. Significantly higher GY and SY were noted after fertilizer application each year compared to the non-fertilized control. The average effect of the fertilizers on GY of WW was control < NPK ≤ digestate + straw ≤ cattle slurry ≤ digestate. Fertilizer application also increased N, S, Na, Zn and Fe content in the grains, especially when digestate was used as fertilizer. However, in non-fertilized plants (control), only the K content increased in the grains, although the uptake of K is positively correlated with GY. Our results show that digestate can be used not only as a replacement for cattle slurry but also as an alternative fertilizer, which, under certain soil conditions, is more effective than NPK fertilizer. [ABSTRACT FROM AUTHOR]

A two-year field and micro-plot 15N-labelled experiment was conducted under two levels of N application rate (240 and 180 kg N ha–1) with three basal N application stages [seeding (L0), four-leaf stage (L4), and six-leaf stage (L6)] to investigate the effects of reducing basal N application amount and postponing basal N fertilization period on wheat growth and N use efficiency (NUE). No significant differences were observed in grain yield, root growth and root morphology between the N180L4 and N240L0 treatments, while the root-shoot ratio of N180L4 was significantly improved. Postponing basal N application period increased the residual basal 15N in soil and reduced basal 15N loss, and N180L4 treatment favored the highest 15N recovery efficiency (NRE), mainly due to reduced 15N loss. Grain yield and basal NRE were significantly positively correlated with root dry weight in deeper soil layers (40–60 cm), and the contribution of root growth to improved grain yield and NRE increased with the downward distribution of the roots. Therefore, postponing the basal N fertilization period under N deficiency promotes deeper root growth during the post-jointing period and increases basal N uptake, as well as reducing basal N loss and increasing grain yield and NUE. [ABSTRACT FROM AUTHOR]

High salt seriously reduces plant growth in wheat by depressing photosynthetic carbon assimilation. In this study, wheat plants were firstly primed with nano-ZnO (50 mg L−1), and after 20-day recovery, the plants were then exposed to a 10-day salt stress (200 mM NaCl). The nano-ZnO priming significantly reduced Na concentration and increased leaf water potential under salt stress. In relation to the non-primed plants, the nano-ZnO primed plants possessed more effective oxygen scavenging system as exemplified by the enhanced activities of SOD, APX and CAT, leading to a better maintenance in homeostasis of ROS production under salt stress. The nano-ZnO priming benefited the tolerance of photosynthetic apparatus to subsequent salt stress, which was mainly due to the enhanced trapped energy flux and electron transport flux. The nano-ZnO priming increased the activities of phosphoglucomutase and cytoplasmic invertase, which promoted the sucrose biosynthesis in leaves under salt stress. In addition, the nano-ZnO primed plants had higher shoot dry weight than the non-primed plants under salt stress. Collectively, nano-ZnO priming activated the antioxidant system to depress the oxidative burst and enhanced the efficiency of photosynthetic electron transport and sucrose biosynthesis in leaves under salt stress, hereby improved the salt tolerance in wheat. [ABSTRACT FROM AUTHOR]

Cleavers (Galium aparine L.) causes severe problems in winter wheat (Triticum aestivum). Four field experiments were performed at Kayakenstky and Stalskiy regions, southern Russia over two growing winter seasons 2015 and 2016 to evaluate postemergence (POST) applications of herbicides (Flucarbazone, metsulfuron, 2,4-D, fluroxypyr, tribenuron, pyroxsulam and sulfosulfuron) applied alone or in tank mixtures on winter wheat cultivars. Wheat injury from herbicide application was minor, with the exception of pyroxsulam + sulfosulfuron in 2015, and tribenuron + pyroxsulam in 2016 at Kayakenstky. Best cleavers control was observed in treatments containing tribenuron. Cleavers were controlled least by metsulfuron (study 1) and flucarbazone (study 2), whereas cleavers had intermediate growth inhibitory responses to the other treatments. Tribenuron + fluroxypyr applied in wheat 'Krasnodar 99', and tribenuron + pyroxsulam in wheat 'Gerda' resulted in enhanced grain yield with the value of 60% and 45.7%, respectively. Overall, tribenuron and herbicides containing tribenuron provided the most efficient control compared to the other herbicides and consistently maintained optimal grain yields in all cases. To improve weed control and to prevent a rapid development of herbicide resistance, tribenuron should be applied in combination with either fluroxypyr, pyroxsulam or metsulfuron. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate influence of zinc (Zn) application on productivity, grain biofortification and grain quality of wheat planted under plough tillage (PT) and zero tillage (ZT) systems. Zn was delivered as soil application (10 kg ha−1), foliage spray (0.025 M) and seed priming (0.5 M) in wheat planted under PT and ZT systems. ZT had higher total soil porosity, total soil organic matter, soil organic carbon and soil microbial biomass carbon than PT. Zn application, by either method, improved grain yield, grain Zn and grain quality in both tillage systems. The grain Zn concentration was 72% and 59% higher with soil-applied Zn in ZT wheat during 2016–2017 and 2017–2018, respectively, compared with no Zn. However, Zn seed priming was the most effective in improving wheat grain yield in both tillage systems. Foliage and Zn soil application were better in improving the indices of Zn use efficiency of Zn. In conclusion, Zn seed priming was the most effective method in improving the wheat grain yield, whereas soil Zn application in ZT and foliar applications in PT were the most effective for grain Zn biofortification. However, Zn soil application was the most cost-effective method of Zn application. [ABSTRACT FROM AUTHOR]

Decomposition of crop residue releases nutrients and preserves soil organic matter dynamics. The decomposition rates of six crop residues namely, corn (Zea mays), dry bean (Phaseolus vulgaris), soybean (Glycine max), potato (Solanum tuberosum), sugarbeet (Beta vulgaris) and spring wheat (Triticum aestivum), were studied at three field-sites: Casselton, North Dakota, USA, and Ada and Downer of Minnesota, USA. Litterbags were placed on soil surface on 31 October 2016, and subset was retrieved after 6 months (8 April 2017) and finally after a year (30 October 2017). Crop residue type had significant effect on remaining mass%, carbon (C) and nitrogen (N) release, and C:N ratio. After 1 year, remaining mass% followed the sequence of corn (82%) > soybean (74%) > wheat (72%) > dry bean (55%) > potato (40%) > sugarbeet (17%). Among sites, Ada had higher remaining biomass C and N than Downer but similar to Casselton. Sugarbeet and corn had the highest (0.0054 d−1) and the lowest (0.0005 d−1) decomposition rate, respectively. Decomposition rate had a close relationship with initial residue C:N ratio. Conversion to intensive corn–soybean rotation might increase the residue load on the surface and reduce C and N mineralization loss. [ABSTRACT FROM AUTHOR]

Soil redox potential (Eh) and pH are fundamentals parameters for plants growth. Measuring soil Eh is essential but complex due to the lack of measurement reliability resulting from high temporal variability and metrological challenges. This paper proposes practical advancements for measuring Eh in aerobic soils using combined electrodes (improvements in methodology specific to cleaning electrodes, measurement time, cleaning the dataset). The study of soil Eh and pH on sunflower and wheat in pot experiments has highlighted the relationship between Ehcumul (Eh associated with a dimension of time) and the portion of porosity that is accessible to air. For reduced soil conditions, sunflower positively reacts to better aeration. Strong correlations exist between the duration of each potential range and the growth of sunflower. The study of sunflower growth in soil reveals extremely harmful impact resulting from too high and/or too low Eh values. [ABSTRACT FROM AUTHOR]

Conservation tillage practices have gained interests. A 2-year field study (2014–2015) was conducted to evaluate four N rates (0, 69, 138, and 207 kg N ha−1) effects on irrigated sweet corn (Zea mays L.) grown with or without wheat (Triticum aestivum L.) residue removal and conventional (CT), reduced (RT), or no-tillage (NT) practices near Shiraz, Iran. After 2 years, maximum marketable yield occurred at 156 and 159 kg N ha−1 under CT and NT, respectively, while yield was tended to be increased with increasing N rates under RT. Increasing N rate increased total plant N uptake, shoot, and grain N accumulation. The lowest nitrogen use efficiency (NUE) was obtained under NT, while RT and CT either showed similar effects or RT was superior over CT. Soil total N was greater under CT and residue retention showed 18% and 14% higher N concentration than residue removal in 2014 and 2015, respectively. Soil organic matter was the highest (2.59%) under RT with residue retention and 138 kg N ha−1. Conservation tillage needs more N rather than CT during transition from conventional to conservation agriculture practices, but it is based on the short-term results and evaluation of long-term experiment is highly recommended. [ABSTRACT FROM AUTHOR]

Organic soil amendments such as biochar are increasingly used to improve the fertility of degraded soils and marginal lands, plant growth, water retention and carbon sequestration. The performance of biochar depends on the parent material, the pyrolysis conditions and the nutrient enrichment process, accounting for the variability of the final products. Recently lignite granulates came into focus offering an alternative characterised by homogeneity, vast availability of the raw material and a standardised production process including nitrogen enrichment through oxidative ammonolysis. In a greenhouse experiment the effects of N-modified lignite granulates (NLG) and composted biochar (BC) on the growth of spring wheat (Triticum aestivum) in a sandy, carbon-free substrate were compared. Additionally, the effect of different NLG application rates (5, 7.5, 11, 15, 28 t ha−1) was investigated. Yields as well as nitrogen and water use efficiency of the soil-plant system were determined at the end of the experiment. Both organic amendments increased yields relative to control plants. An increase in yield, nitrogen and water use efficiency for NLG even at low application rates and a better growth performance compared to BC were observed. Present findings, therefore, indicate, that such granulates offer an alternative to existing organic soil amendments. [ABSTRACT FROM AUTHOR]

Field experiments for six seasons (2008–2013) for present time slice (PTS; 2008–2013) and simulation studies for mid-century (MC; 2021–2050) were carried out to assess different planting dates, varieties and irrigation schedules in addressing the impact of climate change on grain yield and water use efficiency (WUE) in bread wheat (Triticum aestivum L.). During field experimentation, WUE (averaged over other treatment) was unaffected by planting date; however, it was 6% higher in late variety (V1) than early variety (V2). Simulation study suggested that in MC, increase in maximum and minimum temperatures compared to PTS would reduce wheat yield by 17–27%. In MC, WUE would be reduced by 14.8% due to shortening of crop duration (1–11 days). The reduction in WUE could be ascribed to relatively more reduction in yield (22%) than evapotranspiration (ET) (4%). The WUE in MC3 (2041–2050) was relatively more than MC1 (2021–2030) and MC2 (2031–2040) due to more yield and less ET. Delaying planting date of wheat crop by 15–30 days in this region emerged as the best adaptation measure to tackle climate change impact for sustaining yield and having higher WUE in MC. [ABSTRACT FROM AUTHOR]

Plant growth-promoting rhizobacteria (PGPR) play an important role in improving crop growth but have not been studied sufficiently. A wire house experiment was conducted in Pakistan to determine the combined effect of inoculating wheat seeds with PGPR on the subsequent growth and yield of the wheat. The experiment included four treatments: T0 – no-inoculation (control), T1 – Azospirillum brasilense inoculation, T2 – Rhizobium pisi inoculation and T3 – co-inoculation with A. brasilense and R. pisi. Development and growth attributes, as well as final yield of wheat, were studied. Co-inoculation of seeds with both strains increased significantly wheat grain yield, the number of grains per plant and 1000-grain weight by 36%, 11% and 17%, respectively, compared to non-inoculated control. While crop growth rate increased for, respectively, 5.5% and 33% at tillering and flag leaf stages, corresponding values for T3 were about 9% and 14% higher than values for sole inoculations in T1 and T2. Co-inoculation also significantly increased leaf epicuticular wax and relative water content as compared to the control treatment. Thus, inoculation of wheat seeds with A. brasilense and R. pisi and their combination is a promising method to improve growth, yield and quality of wheat. [ABSTRACT FROM AUTHOR]

Grain phosphorus (P) and phytate contents are important for early growth and quality of wheat, respectively. We studied seed P and phytate contents of 57 wheat genotypes released during last 6 decades. The grain total P and phytate P concentrations ranged from 2.0 to 8.9 mg g−1 and 1.6 to 4.7 mg g−1, respectively. Grain P was higher in genotypes released in current or last decade than pre-green revolution period and it correlated well with grain phytate contents. Indicating that breeders worked only for increased grain P and did not consider the phytate contents. Twenty-five genotypes were selected based on differences in grain P and phytate contents to observe the P use efficiency under field conditions. Genotypes differed significantly for grain P and yield at both 0 and 60 kg ha−1 P levels. In conclusion, phytate fraction in grains of recent wheat genotypes was more as compared to old genotypes and genotype Inqlab-91 and Chakwal-86 had maximum grain total P. Moreover, number of productive tillers, spikelet per spike, grain weight, harvest index and grain P concentration and uptake were found responsible for P tolerance under P deficiency. [ABSTRACT FROM AUTHOR]

A pot experiment investigated the effects of root diseases (Pythium and Rhizoctonia) under drought conditions at either tillering or anthesis stages on the water-use efficiency (WUE), water relations, and yield components of wheat cultivars Janz and Mulgara. The pathogens reduced transpiration in Janz during drought at tillering and in both cultivars during the period of recovery after drought at anthesis. However, the pathogens did not affect WUE. WUE did not differ between well-watered plants and those droughted at tillering but it was reduced by 80% by drought at anthesis. Un-infected plants of cultivar Janz subjected to drought at tillering had a higher total water potential (Ψw) and osmotic potential (Ψs) than diseased plants. However, Ψs of un-inoculated plants that were droughted at anthesis was lower than diseased plants in the period following anthesis. Yield components were significantly higher in well-watered than droughted plants and higher in cv. Mulgara than cv. Janz. The pathogens affected transpiration during tillering, but not at later stages, when roots developed beyond the inoculation point. Although the pathogens caused damage to the roots, the effects on water relations parameters were minor. This suggests that wheat can tolerate moderate levels of these root diseases under drought. [ABSTRACT FROM AUTHOR]

High levels of phosphorus (P) often induce zinc (Zn) deficiency in plants grown on Zn-poor soils. We investigated P-induced Zn deficiency in durum wheat (Triticum durum L. 'Carpio') grown on 16 noncalcareous and 31 calcareous soils differing in levels of available (Olsen) P and available (diethylenetriaminepentaacetic acid (DTPA)-extractable) Zn using micropots. A completely randomized factorial design with two levels of P (0 and 40 mg P kg−1 soil) and Zn (0 and 3 mg Zn kg−1 soil), i.e. four treatments ('control', + P, + Zn, and + PZn), were used. Grain yield of control plants depended mainly on the Olsen P level. Phosphorus had a negative effect on yield in 6 soils with Olsen P/ZnDTPA > 25, and Zn a positive one in 5 soils with Olsen P/ZnDTPA > 50; and the + PZn treatment generally resulted in the highest yield. Grain Zn concentration of control plants was negatively correlated with growth and Olsen P. Calcareous soils were less sensitive to P-induced Zn deficiency than noncalcareous soils because phosphate is sorbed by calcite rather than being co-adsorbed with Zn on the Fe oxides. Co-application of P and Zn to soil at low and application of Zn at high Olsen P ensured both maximum yield and grain Zn bioavailability. [ABSTRACT FROM AUTHOR]

Straw incorporation is a useful management practice in sustainable agricultural systems to improve soil fertility and to reduce air pollution from straw burning. A three-year field experiment was conducted under two rice straw managements and four nitrogen (N) application rates in Rugao, China during 2010-2013, to examine whether straw management practices integrated with fertilizer N applications affect crop yield, N balance and N use efficiency in the wheat season of rice-wheat cropping systems. The results showed that straw incorporation had positive effects on plant N uptake and grain yield. This may be attributed to the greater soil water content and lower amount of seasonal rainfall. However, straw incorporation resulted in lower soil inorganic N and more N surplus at the early growth stage. Grain yield had a significant relation with wheat N uptake from sowing to jointing and from jointing to anthesis with straw incorporation. Therefore, our results suggest that in adjusting the ratio of basal and topdressing N fertilizer, it is important for the supply of optimum N to the crop and to maintain grain production with straw incorporation. [ABSTRACT FROM AUTHOR]

Tropospheric ozone (O3) is considered harmful to agriculture production and soil community. Wheat cultivars HD 2987 (O3 sensitive) and Kharchiya 65 (O3 tolerant) were grown under ambient and elevated (ambient + 30 ppb) levels of O3 (EO) using open top chambers, and microbial biomass and enzymatic activities were investigated in soil rhizosphere. Elevated O3 declined soil enzymatic activities related to carbon cycling viz. β-glucosidase, cellobiohydrolase, cellulase and amylase more in sensitive cultivar compared to tolerant. Enzymatic activities linked to nitrogen cycling like N-acetyl-glucosaminidase and urease decreased while protease and glycine aminopeptidase increased. Microbial biomass carbon and nitrogen declined more in sensitive cultivar by 11.1 and 21.2%, respectively. Root biomass reduced in wheat cultivars with an increase of their phenolics contents by 34.3 and 10.2% in HD 2987 and Kharchiya 65, respectively at 60 days after germination. Non-significant changes were observed in soil organic carbon and total nitrogen in both the cultivars. Redundancy analysis suggested that soil enzymatic activities were predominantly affected by O3 induced changes in microbial biomass carbon and root biomass. Study also showed that rhizosphere of sensitive cultivar HD 2987 was affected more under EO as compared to tolerant Kharchiya 65. [ABSTRACT FROM AUTHOR]

Congregated information on maize and wheat root morphology and their distribution as influenced by tillage and soil physical conditions is meager. Root growth under no-tillage (NT) or conventional tillage (CT) is variable: Under NT, higher bulk density slows root elongation and provides shorter roots but simulate root branching; results may be opposite depending on soil texture. Under CT, soil compaction may have negative effects on root growth, with roots exhibiting plasticity. In humid climates, low soil temperatures can reduce root length density (RLD) and increase the diameter of spring cereals under NT. Tillage intensity induces a different distribution of nutrients, a trend which increases with time resulting in higher RLD in the topmost layer of NT. Compared to maize it is difficult to present an overview of the effect on tillage on the RLD of wheat due to inconclusive results. Adequate placements of banded starter fertilizer will effectively build up an early root system of maize, especially at suboptimal growth temperatures. Many studies reported a higher or similar grain yield of maize or wheat under NT compared to CT in temperate climates. However, the limited information or the conflicting results will promote the topic for inclusion in future breeding programs. [ABSTRACT FROM AUTHOR]

This study provided an insight on improving soil-plant micronutrients availability in response to poultry manure (PM), wheat milling residues (WMR) and urea N (UN) and their integration in wheat-soybean cropping system. The treatments were: control; poultry manure full, PM100; wheat milling residues full, WMR100; urea N full, UN100; PM half and WMR half, PM50+WMR50; UN50+PM50; UN50+WMR50; UN50+PM25+WMR25. All amendments were added at the rate or equivalent to 100 kg total N ha-1. Results indicated that the integrated treatments increased Cu, Fe, Mn and Zn uptake of wheat by 35.7-103%, 48.4-111.1%, 85.2-267.0% and 33.8-128.2%, respectively over control. In soybean the corresponding increase in micronutrient uptake (Cu, Fe, Mn and Zn) was 18.3-60.3%, 27.5-87.4%, 14.1-54.6% and 13.2-58.0% in integrated treatments. The post-harvest soil analysis indicated 2 to 3-fold increase in micronutrient content with highest values in PM100 i.e., 2.66 mg kg−1 for Cu, 14.41 mg kg−1 for Fe, 18.58 mg kg−1 for Mn and 2.44 mg kg−1 for Zn, respectively. The results showed that the PM either alone or in integrated with WMR and UN can be an effective management strategy for improving micronutrient content of soil-plant. [ABSTRACT FROM AUTHOR]