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Environmental benefits can be achieved by organic farming systems; however, weed pressure and timely crop nutrition remain important drawbacks for many field crops. Agroecological practices, such as double cropping (e.g., intercropping and relay cropping), using forage legume species can provide nitrogen (N) to the companion crop through biological N fixation and tackle weed issues by competing for light, water and land. The present study investigated the effect of intercropping (IC) and relay-cropping (RC) systems of durum wheat (Triticum turgidum subsp. durum (Desf.) Husn) and forage legumes (Trifolium subterraneum L., Medicago polymorpha L., and Lotus corniculatus L.) by varying organic N fertilization with the aim to reduce N-requirement and weed pressure and increase wheat grain yield and grain protein content in Mediterranean organic farming systems. N fertilizer significantly improved wheat grain yield and grain protein, while a null effect on legume and weed biomass yields was found. Double cropping (T. durum-M. polymorpha, and T. durum-L. corniculatus) enhanced wheat grain yield as compared to the control and the T. durum-T. subterraneum. IC significantly improved legume yield, grain protein and the land equivalent ratio (LER) and reduced weed dry biomass as compared with the RC and the control. Among legume species, T. subterraneum outperformed the others and was less affected by the wheat's competitive performance. Nonetheless, M. polymorpha was as effective as T. subterraneum in controlling weeds. Weed dry biomass was linearly reduced by increasing legume yield; the relationship improved by cumulating wheat grain yield to legume yield. Overall, this study indicated that double cropping, especially IC, can be a suitable agroecological practice to tackle weed issues and reduce N-requirement in Mediterranean organic cereal-based systems. [ABSTRACT FROM AUTHOR]

Environmental benefits can be achieved by organic farming systems; however, weed pressure and timely crop nutrition remain important drawbacks for many field crops. Agroecological practices, such as double cropping (e.g., intercropping and relay cropping), using forage legume species can provide nitrogen (N) to the companion crop through biological N fixation and tackle weed issues by competing for light, water and land. The present study investigated the effect of intercropping (IC) and relay-cropping (RC) systems of durum wheat (Triticum turgidum subsp. durum (Desf.) Husn) and forage legumes (Trifolium subterraneum L., Medicago polymorpha L., and Lotus corniculatus L.) by varying organic N fertilization with the aim to reduce N-requirement and weed pressure and increase wheat grain yield and grain protein content in Mediterranean organic farming systems. N fertilizer significantly improved wheat grain yield and grain protein, while a null effect on legume and weed biomass yields was found. Double cropping (T. durum-M. polymorpha, and T. durum-L. corniculatus) enhanced wheat grain yield as compared to the control and the T. durum-T. subterraneum. IC significantly improved legume yield, grain protein and the land equivalent ratio (LER) and reduced weed dry biomass as compared with the RC and the control. Among legume species, T. subterraneum outperformed the others and was less affected by the wheat’s competitive performance. Nonetheless, M. polymorpha was as effective as T. subterraneum in controlling weeds. Weed dry biomass was linearly reduced by increasing legume yield; the relationship improved by cumulating wheat grain yield to legume yield. Overall, this study indicated that double cropping, especially IC, can be a suitable agroecological practice to tackle weed issues and reduce N-requirement in Mediterranean organic cereal-based systems.

Potato virus Y (PVY) is an aphid-borne plant virus that causes substantial yield losses in potato production. Control measures of the viral infection are both limited and expensive. A proper use of mixed-cropping strategy can reduce the spread of PVY. In this paper, we formulate and analyze a mathematical model of PVY spread in a mixed-cropping system. Then, we extend the model to an optimal control problem by considering use of mineral oil, insecticide and farmer’s level of field inspection for infected plants. The analytic results show that the basic reproduction number ℜ0, a threshold parameter that decides properties of the dynamics. The disease free equilibrium is stable if ℜ0 < 1 and unstable when ℜ0 > 1. It is found that ℜ0, and hence, the disease dynamics is highly sensitive to the representative parameters of density the non-host plant and its quality in attracting vectors. The model exhibits forward bifurcation at ℜ0 = 1. The study of optimal control problem suggests that mixed-cropping combined with either mineral oil or insecticide is the best to control the disease. Furthermore, simulation results show that mixed-cropping can be used as an alternative strategy and can reduce the need of mineral oil or insecticide. [ABSTRACT FROM AUTHOR]

Forage has a significant association with animal nutrition because it is an essential part of milk and meat production in the livestock industry. Thus, for the production of high-quality forage, cereal–legume mixed cropping is an efficient method for meat and milk production in the livestock sector. In a two-year experiment between 2020 and 2021, the forage yield, nutritional compositions, amino acid profile, and forage quality were evaluated in the mixed cropping of winter wheat and ryegrass with alfalfa. In this study, a split-plot design with a randomized block design was employed with three sampling replicates. Cultivars were harvested at three maturity stages, namely, flowering, milk, and soft dough, depending on the wheat growth stage. The experimental results show that wheat 2 (Baomai 9)–alfalfa and ryegrass–alfalfa mixed cropping produced higher fresh biomass output than mono-cropping of wheat and ryegrass harvested at the flowering stage. Furthermore, the dry matter (DM) percentage range increased from 20.18% to 36.39%. By contrast, crude protein, crude fiber, neutral detergent fiber, and acid detergent fiber were higher at the flowering stage than at other harvesting stages with DM values of 14.28%, 34.12%, 55.06%, and 32.55%, respectively. Ryegrass–alfalfa mixing yielded higher values of mineral compositions, and T5 (Baomai 9–alfalfa) generally achieved more extraordinary amino acid compositions. The results demonstrate that wheat and ryegrass with alfalfa mixed cropping, and harvesting at the flowering period produces high-quality forage. Additionally, mixed cropping with alfalfa remarkably affected forage quality parameters, while mixed cropping of wheat cultivar 2 (Baomai 9) and alfalfa obtained the highest dry matter intake, digestible dry matter, relative feed value, total digestible nutrient, relative forage quality, and quality index values of 2.56, 68.54, 136.49, 60.50, 127.41, and 1.69, respectively. Thus, the mixed-cropping of wheat and ryegrass with alfalfa forage is recommended for its maximized quality forage production and nutritional values in livestock feedstuff. [ABSTRACT FROM AUTHOR]

Potato virus Y (PVY) is a serious pathogen that causes yield reduction and seed degeneration in potatoes crops. It is transmitted non-persistently by a wide range of aphid vectors. The transmission process is rapid and can be affected by vector behavior exhibited during host search and feeding. Controlling aphids by insecticide is inefficient to manage PVY while, mixed-cropping system comprises potatoes and non-host crop plants is an important strategy. Studies about the significance of such practices will benefit smallholder farmers. We formulate a mathematical model that aims to investigate effects of mixed-cropping system on the PVY disease dynamics. Analysis results show that the non-virus host plant is important to reduce the basic reproduction number, ℜ 0 of the disease. If ℜ 0 < 1 , then the disease-free equilibrium is globally stable; if ℜ 0 > 1 , then an endemic equilibrium exists which is locally asymptotically stable. We employed a geometric approach and discuss conditions for global stability of the endemic equilibrium. Bifurcation and sensitivity analysis of the embedded parameters were also carried out. Finally, some numerical simulations are conducted to support analytic results. [ABSTRACT FROM AUTHOR]

Potato virus Y (PVY) is an aphid-borne plant virus that causes substantial yield losses in potato production. Control measures of the viral infection are both limited and expensive. A proper use of mixed-cropping strategy can reduce the spread of PVY. In this paper, we formulate and analyze a mathematical model of PVY spread in a mixed-cropping system. Then, we extend the model to an optimal control problem by considering use of mineral oil, insecticide and farmer’s level of field inspection for infected plants. The analytic results show that the basic reproduction number ℜ0, a threshold parameter that decides properties of the dynamics. The disease free equilibrium is stable if ℜ0 < 1 and unstable when ℜ0 > 1. It is found that ℜ0, and hence, the disease dynamics is highly sensitive to the representative parameters of density the non-host plant and its quality in attracting vectors. The model exhibits forward bifurcation at ℜ0 = 1. The study of optimal control problem suggests that mixed-cropping combined with either mineral oil or insecticide is the best to control the disease. Furthermore, simulation results show that mixed-cropping can be used as an alternative strategy and can reduce the need of mineral oil or insecticide.

Climate is changing at an alarming rate, imposing significant negative impacts on the quantity and nutritional quality of the economical crop yield. Overreliance on staple cereals that demand high inputs has ecological, economic, and nutritional risks. Nutritional profiles of major food crops are being degraded under changing climate and the global micronutrient malnutrition called 'hidden hunger' causes severe health impacts on developing countries in the world. Elevated atmospheric temperature and CO2 concentration have reduced iron (Fe) and zinc (Zn) levels of major food crops, thus, leading to dietary deficiencies of these micronutrients, constituting a major public health concern. Food legumes, which are highly suitable crops in the low-input farming systems, are a well-known source of Fe and Zn. Further, low-input farming systems have been reported as an integral component in climate-resilient food systems. Efficient use of existing genetic diversity of food legumes could improve the nutritional output of cropping systems, thereby sustaining human Fe and Zn nutrition in the face of global climate change. This review explores and describes the underexploited potentials of food legumes to be used as an integral component in low-input food-production systems adapted to climate change to combat micronutrient malnutrition, particularly focusing on Fe and Zn, which are of significant concern as key drivers of global micronutrient malnutrition. [ABSTRACT FROM AUTHOR]

The biggest problem of Hungarian crop farming is mass production and the simple crop rotation based on cereals. There was a decrease in sowing area of protein crops which raises crucial issues in crop rotation and land use. Therefore, growing papilionaceous plants, which are now considered to be alternative plants, should be taken under close examination. Hairy vetch (Vicia villosa Roth.) belongs to the family of papilionaceous plants and it can be grown in light weak soils. In Hungary, hairy vetch was used as green forage at first, but it later became a green manure plant. Nowadays, it is used as a cover crop and its sowing seed has a good export market. In low fertile soils it is able to produce a big amount of green yield (25-40 t ha-1) even in spring while its seed yield could be 0.4-0.5 t ha-1 at farm level. In addition to its morphological characteristics hairy vetch is grown mainly with a supporting plant, i.e. triticale in many cases. Our purpose was to test the harvest index and its agrotechnical and botanical factors of hairy vetch in different cropping systems. [ABSTRACT FROM AUTHOR]

In tropical regions, the contributions and limitations of agroecosystems have been identified with respect to bird diversity conservation. It has been suggested that agroecosystems can have different conservation values, according to the structural complexity of the vegetation (e.g., higher number of vegetation strata, cultivated species diversity, among others). Therefore, agroecosystems, especially those with a smaller area (e.g., small-holdings), could be crucial for developing bird conservation strategies. In order to establish the contribution of different agroecosystem types to bird conservation in the department of Caldas (Colombia), we compared bird richness, abundance, and similarity associated to three types of habitats: (1) type I agroecosystems (mono-cropping with bare soil), (2) type II agroecosystems (mixed-cropping, grazing pastures with weeds and dispersed trees, and plantations with understory), and (3) secondary forests. Type II agroecosystems did not differ in bird richness and similarity compared to secondary forests, and species with high sensitivity to disturbance were registered (Zentrygon frenata, Phaetornis guy, Phaetornis syrmatophorus, Lepidocolaptes lacrymiger and Sphenopsis frontalis). Additionally, we registered a species of global conservation interest (Chloropipo flavicapilla) and four migratory species (Catharus ustulatus, Parkesia noveboracensis, Setophaga fusca and Setophaga striata) in this type of agroecosystem. Thus, type II agroecosystem habitats are not completely negative on avifauna, and they could serve an important role within conservation strategies in rural landscapes.

Copyright of Acta Agronomica Sinica is the property of Crop Science Society of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Biodiversity‐based agricultural systems can improve production efficiency and sustainability, with fewer negative environmental impacts and lower use of external inputs. Mixed‐cropping and rice‐duck co‐culture have been shown to produce ecological benefits and to have positive effects on paddy soil. However, the effects of a combination of mixed cropping with different rice cultivars and duck co‐culture on soil nutrients availability and grain yields have not been evaluated. A paddy field experiment was carried out over two rice growing seasons to test these effects. RESULTS: Several combinations of rice cultivars, when integrated with duck co‐culture, significantly increased the soil organic matter and total nitrogen contents during the rice growing seasons, as compared to mono‐cropping systems. In mixed‐cropping combined with duck co‐culture (MCDC) systems, the soil alkali‐hydrolyzable nitrogen content ranged from 4.33% to 17.86% higher than that in mono‐cropping systems. Similar increases were found for soil available phosphorus (8.71–15.91%) and soil available potassium (8.65–39.43%) contents. Furthermore, MCDC produced higher grain yields and harvest indexes for both study seasons. CONCLUSION: The integration of MCDC systems had positive effects on soil nutrient contents of paddy fields, which could, in turn, lead to yield enhancements, as well as additional income for farmers in the form of organic duck meat. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

With the rapid development of agricultural industrialization, agricultural nonpoint source pollution, which occurs when synthetic chemical additives (e.g. fertilizer, pesticides, and herbicides) runoff into rivers or lakes, has become a major concern. To explore the approaches of reducing the application of chemical additives, we conducted a field experiment to test whether the integrated farming systems would alleviate the nonpoint source pollution. Specifically, we tested whether mixed-cropping or mixed-cropping plus duck co-culture (MCDC) systems with optimized rice (Oryza sativa L.) cultivars could reduce nutrients runoff or leaching from paddy field. We found that compared to the mono-cropping systems, the electrical conductance (EC), oxidation-reduction potential (ORP), the contents of dissolved oxygen (DO), nitrates (NO3-), ammonium (NH4+), total nitrogen (TN), total phosphorus (TP) and total potassium (TK) of paddy water in MCDC systems all increased during the rice-growing stages. The contents of the TN, TP, and TK of paddy water in MCDC systems were 45.35%, 52.43% and 40.47% higher than those in the mono-cropping systems, respectively. Compared to the conventional mono-cropping, the mixed-cropping systems could alleviate nonpoint source pollution by decreasing the application of synthetic chemicals to rice paddies, the rice-duck co-culture system had significantly lower additions of agro-chemicals to paddy fields, which decreased the loss/runoff/leaching rates of nitrogen, phosphorus and potassium from paddy fields into the surrounding water areas by 32.73%, 8.72% and 31.88%, respectively. Considering that the MCDC systems exerted similar/even better performances as/than the rice-duck co-culture system and the rice mixed-cropping system, we deduced that the MCDC systems could also could alleviate nonpoint source pollution to a certain extent. [ABSTRACT FROM AUTHOR]

Industrial agriculture with intensive use of herbicides and pesticides has resulted in a great reduction of biodiversity and negative environmental impacts on rice paddy fields. Biodiversity-based farming systems can improve production efficiency and sustainability, with fewer negative environmental impacts and lower use of external inputs. Previous studies have reported that both the rice-duck co-culture systems and mixed-cropping systems with different rice cultivars can suppress weed communities and control harmful pests. However, little is known about the effects of an integration of mixed-cropping with different rice cultivars and rice-duck co-culture on weed communities and pests in paddy fields. Four combinations with three replications of each treatment were employed, half with and half without ducks in paddy fields, which were compared with mono-cropping systems of the five rice cultivars. After two-season experiments, we found that species richness and diversity of weed communities in the mixed-cropping with rice-duck co-culture (MCDC) systems were significantly lower than those in the mono-cropping systems. The abundance of rice leaf roller in the MCDC systems was also significantly lower than that in the mono-cropping systems. Our findings indicated that the biodiversity-based farming would be an environmentally friendly approach to control weeds and rice leaf roller without using herbicides or pesticides in paddy fields, and hence to produce more safe, healthy, and high-quality rice and duck meat. [ABSTRACT FROM AUTHOR]

To explore the effects of different densities of mixed-cropping on 13C-photosynthate distribution and grain yield of maize, we measured photosynthetic characteristics, 13C-photosynthate distribution, dry matter accumulation, and grain yield under different planting densities (LD, 67500 plants µ hm-2 and HD, 97500 plants µ hm-2) under mixed-cropping (M, 1:1, 2:2) and monoculture of Zhengdan958 (ZD) and Denghai605 (DH). The results showed that with the increases of planting density, grain yield, 13C-photosynthate allocation to grain, dry matter accumulation, and leaf area index (LAI) increased, but the chlorophyll content and net photosynthetic rate decreased. No significant difference was observed between the monoculture and mixed-cropping at the density of 67500 plants µ hm-2. However, at 97500 plants µ hm-2, LAI, chforophyll content, net photosynthetic rate and dry matter accumulation in mixed-cropping were higher than that in monoculture. Mixed-cropping promoted the transport of dry matter from the vegetative organs such as stem to the grain and the distribution of 13C-photosynthates to grain. Grain yield of summer maize significantly increased in mixed-cropping due to the increase of 1000-grain mass. Under high plant density, the mixed-cropping could enlarge photosynthetic area, maintain higher net photosynthetic rate, increase dry matter accumulation, improve the distribution of dry matter, promote the distribution of 13C-photosynthates to grains and thus increase the grain yield. Our results indicated that mixed-cropping could significantly increase the yield of close planting summer maize in Huang-Huai-Hai Plain. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agronomica Sinica is the property of Crop Science Society of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In tropical regions, the contributions and limitations of agroecosystems have been identified with respect to bird diversity conservation. It has been suggested that agroecosystems can have different conservation values, according to the structural complexity of the vegetation (e.g., higher number of vegetation strata, cultivated species diversity, among others). Therefore, agroecosystems, especially those with a smaller area (e.g., small-holdings), could be crucial for developing bird conservation strategies. In order to establish the contribution of different agroecosystem types to bird conservation in the department of Caldas (Colombia), we compared bird richness, abundance, and similarity associated to three types of habitats: (1) type I agroecosystems (mono-cropping with bare soil), (2) type II agroecosystems (mixed-cropping, grazing pastures with weeds and dispersed trees, and plantations with understory), and (3) secondary forests. Type II agroecosystems did not differ in bird richness and similarity compared to secondary forests, and species with high sensitivity to disturbance were registered (Zentrygon frenata, Phaetornis guy, Phaetornis syrmatophorus, Lepidocolaptes lacrymiger and Sphenopsis frontalis). Additionally, we registered a species of global conservation interest (Chloropipo flavicapilla) and four migratory species (Catharus ustulatus, Parkesia noveboracensis, Setophaga fusca and Setophaga striata) in this type of agroecosystem. Thus, type II agroecosystem habitats are not completely negative on avifauna, and they could serve an important role within conservation strategies in rural landscapes. [ABSTRACT FROM AUTHOR]

Degree of arbuscular mycorrhizal (AM) association and its diversity were investigated in the coconut palm ( Cocos nucifera L.) cultivated in crop mixed system under rain-fed condition in a highly productive humid tropical zone in Malappuram district of Kerala, India. Forty AM species belonging to ten genera viz. Acaulospora, Claroideoglomus, Dentiscutata, Diversispora, Funneliformis, Gigaspora, Glomus, Redeckera, Scutellospora and Septoglomus were recorded indicating high level of AM richness in coconut rhizosphere . Of these, eighteen AM fungal species are being reported for first time from this palm. Claroideoglomus, Glomus and Gigaspora were the most commonly present genera and Claroideoglomus etunicatum and Glomus aggregatum the common species. The diversity indices (Shannon indices values) of AM fungi associated with coconut palm in a crop mixed system and mono crop varied significantly. The Shannon index, Simpson's index and evenness ranged from 1.40 ± 0.10 to 2.70 ± 0.01, 0.65 ± 0.033 to 0.90 ± 0.004, 0.51 ± 0.01 to 0.82 ± 0.01, respectively. Correlation between soil physio chemical characters and mycorrhizal parameters were worked out. Soil pH had negative correlation with spore count, root colonization, species richness, Shannon H and Simpson indices but had positive correlation with species evenness. Electrical conductivity showed positive correlation with root mycorrhizal colonization which indicated active AMF mediated uptake of nutrients. [ABSTRACT FROM AUTHOR]

To explore the effects of different densities of mixed-cropping on 13 C-photosynthate distribution and grain yield of maize, we measured photosynthetic characteristics, 13 C-photosynthate distribution, dry matter accumulation, and grain yield under different planting densities (LD, 67500 plants·hm -2 and HD, 97500 plants·hm -2 ) under mixed-cropping (M, 1:1, 2:2) and monoculture of Zhengdan958 (ZD) and Denghai605 (DH). The results showed that with the increases of planting density, grain yield, 13 C-photosynthate allocation to grain, dry matter accumulation, and leaf area index (LAI) increased, but the chlorophyll content and net photosynthetic rate decreased. No significant difference was observed between the monoculture and mixed-cropping at the density of 67500 plants·hm -2 . However, at 97500 plants·hm -2 , LAI, chlorophyll content, net photosynthetic rate and dry matter accumulation in mixed-cropping were higher than that in monoculture. Mixed-cropping promoted the transport of dry matter from the vegetative organs such as stem to the grain and the distribution of 13 C-photosynthates to grain. Grain yield of summer maize significantly increased in mixed-cropping due to the increase of 1000-grain mass. Under high plant density, the mixed-cropping could enlarge photosynthetic area, maintain higher net photosynthetic rate, increase dry matter accumulation, improve the distribution of dry matter, promote the distribution of 13 C-photosynthates to grains and thus increase the grain yield. Our results indicated that mixed-cropping could significantly increase the yield of close planting summer maize in Huang-Huai-Hai Plain.