Legume-based Cropping Systems Research Articles

Productivity and Profitability of Diversified Legume-based Cropping Systems in the Indo-gangetic Plains of India as Influenced by Nutrient Management

Background: The continuing adoption of the rice-wheat cropping system (RWCS) and indiscriminate use of inorganic fertiliser has led to a decrease in soil fertility, an increase in multiple micronutrient deficiencies, a decrease in the water table and excessive greenhouse gas emissions, especially in the Indo Gangetic Plains. Adoption of crop diversification strategies, including legumes in cropping systems with integrated use of organic and inorganic nutrient sources, could be a viable option for achieving higher fodder tonnage and sustainable crop production in aforesaid ecologies. Methods: A field experiment was conducted during the kharif, rabi and summer seasons of 2018-19 and 2019-20 in a split-plot design comprising four cropping systems (CS) i.e., rice-wheat, rice-berseem, pearl millet-oats-moong bean and maize-cowpea-wheat in main plots; and four nutrient management (NM) practices i.e., 100% RDF (recommended dose of fertiliser), 100% RDF + cow urine (foliar spray), 100% RDF + PGPR (seed treatments) and 75% RDF + cow urine + PGPR were assigned in sub-plots with three replications of each treatment. Result: Investigations revealed that the significantly highest system productivity, net returns and higher nutrient availability were obtained under the rice-berseem cropping system with 100% RDF + PGPR treatment. The magnitude of increment in system productivity of the rice–berseem cropping system was 35.06, 57.87 and 87.29% over rice-wheat, maize-cowpea-wheat and pearl millet-oats-moong bean cropping system, respectively. The legume-based cropping system has strengthened and sustained crop productivity and profitability. The results of the present work confirmed that the adoption of legume-based crop diversification has significantly alleviated the crop yield of dairy-based farming systems.

Differences in productivity and soil properties in rice-based cropping systems under long-term organic, integrated and conventional production

ABSTRACT This study investigated the effects of four rice-based cropping systems (rice-vegetable pea + coriander; rice-chickpea + coriander; rice-potato and rice-wheat) cultivated in long-term organic, integrated and conventional production systems on system productivity (SP), soil organic carbon (SOC) sequestration and soil properties. The experiment was laid out in a split plot design with the production system assigned to the main plots and the cropping system to sub-plots. The results revealed that SP, SOC content and SOC sequestration in the organic system were significantly higher than in the conventional counterpart (17.1%, 59.4% and 165.9% higher, respectively). The fractions of total organic carbon followed the order: very labile carbon > non-labile carbon > labile carbon > less labile carbon. The soil in the organic system had, in general, the most improved physical (water holding capacity, bulk density), chemical (available N, P, K and S, and DTPA-extractable Fe, Mn, Cu and Zn) and biological properties (dehydrogenase and acid and alkaline phosphatase activity), especially when compared with the conventional system. The legume-based cropping systems (rice-chickpea + coriander and rice-vegetable pea + coriander) enhanced the SP, SOC content and SOC sequestration by 22.6% and 46.5%, 16.3% and 11.9% and 47.5% and 29.4%, respectively, compared with the rice-wheat cropping system, with improvements also in different physical, chemical and biological soil properties. Thus, organic system with legume-based cropping (rice-chickpea + coriander and/or rice-vegetable pea + coriander) was concluded to sustain crop productivity and have greater soil carbon sequestration potential in the longer term.

Impact of diversified cropping systems and fertilization strategies on soil microbial abundance and functional potentials for nitrogen cycling

Diversified cropping systems and fertilization strategies were proposed to enhance the abundance and diversity of the soil microbiome, thereby stabilizing their beneficial services for maintaining soil fertility and supporting plant growth. Here, we assessed across three different long-term field experiments in Europe (Netherlands, Belgium, Northern Germany) whether diversified cropping systems and fertilization strategies also affect their functional gene abundance. Soil DNA was analyzed by quantitative PCR for quantifying bacteria, archaea and fungi as well as functional genes related to nitrogen (N) transformations; including bacterial and archaeal nitrification (amoA-bac,arch), three steps of the denitrification process (nirK, nirS and nosZ-cladeI,II) and N2 assimilation (nifH), respectively. Crop diversification and fertilization strategies generally enhanced soil total carbon (C), N and microbial abundance, but with variation between sites. Overall effects of diversified cropping systems and fertilization strategies on functional genes were much stronger than on the abundance of bacteria, archaea and fungi. The legume-based cropping systems showed great potential not only in stimulating the growth of N-fixing microorganisms but also in boosting downstream functional potentials for N cycling. The sorghum-based intercropping system suppressed soil ammonia oxidizing prokaryotes. N fertilization reduced the abundance of nitrifiers and denitrifiers except for ammonia-oxidizing bacteria, while the application of the synthetic nitrification inhibitor DMPP combined with mineral N reduced growth of both ammonia-oxidizing bacteria and archaea. In conclusion, this study demonstrates a strong impact of diversified agricultural practices on the soil microbiome and their functional potentials mediating N transformations.

Effect of crop diversification and sowing technique on productivity, economics, water productivity and soil properties of wheat (Triticum aestivum)-based cropping systems

Conventionally intensive tillage and sowing practices, and existing cereal crop-based system has been declining soil fertility resulting in poor grain yield and quality. In order to enhance system-based productivity and it becomes necessary to diversify cereal crop through legume-based cropping system with conservation technology-based tillage and crop sowing method. Hence, a study was carried out during 2018–2022 under Farmer First Project (FFP) at Morena district in Madhya Pradesh (Rajmata Vijayaraje Scindia Krishi Vishwa Vidyalaya, Gwalior, Madhya Pradesh) to collate the wheat (Triticum aestivum L.)-based four cropping systems with rainy (kharif) season crops i.e. pearl millet [Pennisetum glaucum (L.) R. Br.], pigeonpea [Cajanus cajan (L.) Millsp.], greengram [Vigna mungo (L.) Hepper] and clusterbean [Cyamopsis tetragonoloba (L.) Taub] and two crop sowing methods, viz. conventionally tilled and permanent broad-bed furrow irrigation were used. Significantly greater improvements were recorded in grain yield of wheat-based cropping systems, net returns, wheat equivalent yield, system protein production, water productivity, net energy gains, energy productivity and soil physico-chemical properties, while saving cultivation cost, total water- use and energy input under permanent broad bed-furrow over conventional tillage and sowing method. Likewise, system-based wheat equivalent yield, system protein productivity, additional net returns, net energy gains, energy productivity and parameters of soil physico-chemical properties were significantly enhanced with pigeonpea-wheat as compared to pearl millet-wheat cropping system. The results of experiment had suggested that cropping system of wheat based can be made more productive and remunerative with the inclusion of legume crops in rainy season and sowing of crop with permanent broad-bed furrow irrigation method.

Optimizing the Nitrogen Use Efficiency in Vegetable Crops

Nitrogen (N) is the most limiting nutrient for the production of vegetable crops, but anthropogenic sources pose risks due to its transformation into several reactive forms and movement throughout the environment. The bulk of the N research to date to improve Nitrogen Use Efficiency (NUE) has followed a reductionist factorial approach focused on synthetic N application rates and crop growth response, under monocultures. The increased adoption of diversified cropping systems, organic N sources, and alternative management practices makes it more challenging to unravel N form transformation, movement, and crop uptake dynamics, in time and space. Here, based on a selected review of the recent literature, we propose a holistic approach of nutrient management to highlight key management and production variables as well as multilevel cropping system, genetic, environmental, ecological, and socioeconomic interactions to improve the N cycle and NUE. The best management strategies to improve NUE include both organic and inorganic N rate calibration studies, germplasm selection, crop rotations, identification of nutrient x nutrient interactions, and pest and water management. Agroecological practices that may improve NUE include vegetational diversification in time and space, integrated crop–livestock systems, conservation tillage, organic amendment inputs, legume-based cropping systems, as well as a landscape approach to nutrient management.

Adding a diversity of legumes to a crop decision-support system: Maintaining satisfactory accuracy while keeping the model simple

In a context of economic and environmental concerns in agriculture, legumes appear to be suitable alternative crops to diversify current cropping systems and reduce their dependence on synthetic nitrogen (N) fertiliser and protein from imported soya bean. However, legume-based cropping systems may increase N losses through nitrate leaching if the N available from legumes does not coincide with subsequent crop requirements. To help agricultural advisers manage N in these systems, we adapted the decision-support system Syst’N®, designed to assess N losses in cropping systems, to simulate three annual and one perennial legume crops: pea, faba bean, soya bean and lucerne. To this end, we adapted and simplified existing submodels of legume functioning to include them in Syst’N, to keep the latter simple. We adapted the submodels “BNF” (i.e. biological N fixation) from the STICS model and “dormancy” from the CropSyst model. We also added the ability to enter the flowering date to improve predictions (improvement in N fixation’s rRMSE from 57% to 41% and EF from 0.57 to 0.77). The equations and associated parameter set developed for the four legume crops yielded satisfying predictions of crop biomass (rMBE = 9%, EF = 0.82, rRMSE = 39%) and N content (rMBE = 5%, EF = 0.76, rRMSE = 37%). These performances support the philosophy of Syst’N® that requires minimising the number of additional parameters for users when representing new crops or processes.

Assessment of Soil Microbial Status under Different Land Use System at Various Depth

The present study was undertaken to assessment of soil microbial status under different land use system at various depth of main campus of University at Acharya Narendra, Deva University of Agriculture and Technology, Kumarganj, Ayodhya (U.P.) during 2018-2019.
 The land use systems selected for study were rice-wheat cropping system (RWCS), legume based cropping system (LBCS), and vegetable based cropping system (VBCS). Plantation land (mango, aonla and bael orchard), forest land (shisham, teak and eucalyptus) and barren land (NSP-6 farm). Soil samples were taken with GPS system from four depths viz. 0-15, 15-30, 30-45 and 45-60cm in order to analyze microbial population (bacteria, fungi and actinomycetes). The bacterial population (cfu × 105 g-1) under all the four land use viz. crop land, plantation land, forest land and barren land was decreased with increasing soil depth, which ranged from 2.76 to 4.95 cfu × 105 g-1 soil. The average bacterial population values were higher in forest land followed by plantation land, crop land and barren land. The fungi population (cfu × 103 g-1) under all the four land use viz. crop land, plantation land, forest land and barren land was, also, decreased with increasing soil depth at all land use system and ranged from 0.85 to 1.77 cfu × 103 g-1 soil. The average fungi population values were higher in forest land followed by crop land, plantation land and barren land. The actinomycetes population (cfu × 104 g-1) under all the four land use viz. crop land, plantation land, forest land and barren land was decreased with increasing soil depth at all land use system. The population varied from 0.57 to 1.02 cfu × 104 g-1 soil. The average actinomycetes population values were higher in forest land followed by plantation land, crop land and barren land.

Depth Wise Studies of Physico-Chemical Properties of Soil under Different Land Use System at Eastern U.P, India

The Present Study was undertaken to assess Depth Wise Studies of Physico-Chemical Properties of Soil under Different Land Use System of main campus of university at Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya (U.P.) during 2018-2019.
 Soil samples were collected under RWCS (Rice-Wheat cropping system), LBCS (Legume based cropping system), and VBCS (Vegetable based cropping System).The land use systems selected for study were Crop land RWCS (Rice-Wheat cropping system), LBCS (Legume based cropping system), and VBCS (Vegetable based cropping System), Plantation land (Mango, Aonla and Bael orchard), Forest land (Shisham, Teak and Eucalyptus) and barren land (NSP-6 farm). Soil samples were taken with GPS system from four depth viz. 0-15cm, 15-30cm, 30-45cm and 45-60cm and analyzed for their physico-chemical properties (soil pH, EC, OC, BD, Available N, P&K). Results revealed that different soil properties varied significantly under different land use system at various soil depths.

Production systems and contributions of grain legumes to soil health and sustainable agriculture: A review

Sustainable development of agriculture is essential, and there is unanimity that diversification of the cropping systems could support sustainable production. Grain legumes are essential in farming systems in terms of food and nutrition security and income generation. Under legume-based cropping systems, these crops are a potential remedy to pest and disease issues, low nutrient supply, biodiversity protection, and food and nutrition insecurity. In this chapter, we highlight the production systems of legumes and their use in sustainable agricultural production. Specifically, we have looked at the benefits of having a legume cropping system in the agroecosystem, production, and farming systems. The function of legumes in improving the potential of crop productivity is a promising approach to tackling the challenges of poor crop yields and improvement in sustainable production. Due to health and environmental benefits, the focus should shift to breeding grain legumes that can fully express their biological nitrogen fixation and other potentials under abiotic and biotic limitations.

Do Conservative Agricultural Practices Improve the Functional Biological State of Legume-Based Cropping Systems?

This study evaluated the response of soil microbial functions to the presence and placement of faba beans in crop rotations (rotation without legumes versus rotations with faba beans as the crop previous to wheat, with the faba beans sown three years before the wheat crops) combined with two tillage systems (conventional and reduced tillage). The study included 36 wheat-producing plots, and two agricultural practice types were defined: high-frequency–low-intensity (HF–LI) and low-frequency–high-intensity (LF–HI). The results demonstrated a significant increase in the total carbon and nitrogen (N) content under reduced tillage. Furthermore, the general path analysis suggested that arylamidase and β-glucosidase activities significantly affect N fluxes. The enzyme activities were modified by changing the soil’s physicochemical properties. These findings highlighted the significance of introducing legumes as the crop preceding wheat, especially when applying conventional tillage. Moreover, it was revealed that farmers’ management of these conservative practices is a leading factor in regulating soil functions. Pesticides and inorganic fertilization inputs were classified as HF–LI practices, while organic matter (OM) inputs and liming treatments were qualified as LF–HI practices. For instance, LF–HI practices (OM inputs and liming) directly and indirectly influenced the soil functions related to the N cycle, while HF–LI practices (pesticide, inorganic N fertilization, and previous crops) resulted in fewer soil function changes.

Assessing the Effectiveness of Zero Tillage and Legume-based Cropping Systems for Enhancing Soil Nitrogen Concentrations and Stocks under Rainfed Pearl Millet Production Systems

Assessing the Effectiveness of Zero Tillage and Legume-based Cropping Systems for Enhancing Soil Nitrogen Concentrations and Stocks under Rainfed Pearl Millet Production Systems

Efficacy of co-inoculation of the rhizobium and pseudomonas in combination with chemical fertilizer on the productivity of rice under legume-based cropping system

The main production restriction in Nepal is a shortage of nitrogen and phosphorus-based fertilizers. In addition, the excessive use of chemical fertilizers to increase rice production alters the soils’ physicochemical and biological qualities. The effective application of biofertilizers obtained from beneficial microorganisms is on demand for increasing agriculture production as well as maintaining soil health sustainably. The experiment was conducted in a completely randomized block design (RCBD) with five treatments and four replications at Grain Legumes Research Program (GLRP), Khajura, Banke in order to find out the response of co-inoculation of Rhizobium and Pseudomonas in combination with different dose of recommended chemical fertilizers. The application of the co-inoculated Rhizobium and Pseudomonas at the dose of 800 g/ha along with the recommended N:P2O5:K2O dose of 100:60:30 kg/ha was found to be best effective among all treatment combinations. The maximum panicle length, biological yield, grain yield and thousand grains weight were 27.75 cm, 6.55 t/ha, 6.083 t/ha, and 27.67 g, respectively. In this study, co-inoculation of Rhizobium, Pseudomonas and a full dose of prescribed chemical fertilizers improved panicle length, biological yield, grain yield and thousand grains weight considerably more than others.

Height to first pod: A review of genetic and breeding approaches to improve combine harvesting in legume crops.

Height from soil at the base of plant to the first pod (HFP) is an important trait for mechanical harvesting of legume crops. To minimise the loss of pods, the HFP must be higher than that of the blades of most combine harvesters. Here, we review the genetic control, morphology, and variability of HFP in legumes and attempt to unravel the diverse terminology for this trait in the literature. HFP is directly related to node number and internode length but through different mechanisms. The phenotypic diversity and heritability of HFP and their correlations with plant height are very high among studied legumes. Only a few publications describe a QTL analysis where candidate genes for HFP with confirmed gene expression have been mapped. They include major QTLs with eight candidate genes for HFP, which are involved in auxin transport and signal transduction in soybean [Glycine max (L.) Merr.] as well as MADS box gene SOC1 in Medicago trancatula, and BEBT or WD40 genes located nearby in the mapped QTL in common bean (Phaseolus vulgaris L.). There is no information available about simple and efficient markers associated with HFP, which can be used for marker-assisted selection for this trait in practical breeding, which is still required in the nearest future. To our best knowledge, this is the first review to focus on this significant challenge in legume-based cropping systems.

Which Innovative Cropping System for Which Farmer? Supporting Farmers' Choices Through Collective Activities

Designing innovative cropping systems is an active field of agricultural research challenged by the agroecological transition. One of the challenges is to adapt cropping systems to the diversity of farms and contexts. For instance, in the cotton production zone of Burkina Faso differences between farm resources, agricultural situations and agronomic constraints have resulted in a wide range of farming systems. In this context, to break with the trend toward cotton production, we co-designed eight legume-based innovative cropping systems (ICS) likely to meet the objectives sought and the constraints faced by a wide range of local farmers, thus constituting a “basket of options”. Our approach was to enable each farmer to choose the option they considered best suited to their conditions. To that end, the ICSs were implemented and discussed with farmers in participatory prototyping trials. After one season of co-evaluating the different ICSs, the farmers taking part in the co-evaluation were able to test an ICS on their own farm, by choosing and adapting one of the options. Thirty-nine farmers out of seventy-three chose an ICS to test. They were asked the reasons for their choice. Their selection criteria were analyzed in relation to comments made during collective activities organized in the participatory prototyping trials. To complete this analysis, we built an expert-based farming system typology and a statistical typology based on data collected in a rural household multi-indicator survey (RHoMIS) of 63 farms participating in this study. The two farming system typologies were compared, and the relationships between farming system types and the ICS tested on the farm were analyzed. We found that farmers did not really base their choice on their farming system. Rather, they used a wide range of criteria that varied from farmer to farmer, and they were influenced by what they had learned during the collective activities organized in the participatory prototyping trials.

Long Term Benefits of Legume Based Cropping Systems on Soil Health and Productivity. An Overview

Increasing land-use pressure and monoculture coupled with inadequate restorative practices pose threat to sustainability, nutrient uptake of crops often exceeds replenishment causing fertility deterioration. Imbalanced and indiscriminate use of fertilizers deteriorates soil health and factor productivity. Long-term impacts on soil nutrient stocks influence the sustainability of crop production are major gains of regular inclusions of legume in a cropping system. Inclusion of green gram in potato cultivation increased organic carbon and nutrients than non-legume based potato cropping systems. Legume-based cropping systems increased soil C and N stock than only cereal based cropping system. Maize intercropped with velvet-bean recorded higher productivity compared with pure maize and pure maize with mineral fertilizers. Bulk density of soil in glyricidia + maize system was lower compared to sole maize and maize grass fallow. Intercropping with glyricidia, glyricidia pruning incorporated into the soil optimized the cation exchange capacity in soil than sole maize system. Higher grain yield of finger millet and sustainable yield index were observed in green leaf manuring. Due to socioeconomic and environmental benefits, legumes could be introduced in cropping systems to reduce external inputs and increase crop diversity. They also found to perform well in conservation systems, intercropping systems, which are very important in developing nations. Legumes fix nitrogen from the atmosphere and aid in the cycle of soil nutrients and water retention. Because of their many uses, legumes have a lot of potential for conservation agriculture, as they can be used as a growing crop or as crop residue.

​Performance of Different Farming Practices in Legume based Cropping System under Mid-hills of H.P. Himalayas

Background: Increasing demands of food, depleting land, degrading land resources and changing climate are some of the important factors driving the cropping systems of any agro-ecological zone in the world. Cropping systems have been traditionally structured to maximize crop yields. Now, there is a strong need to design cropping systems which take into consideration the emerging social, economical and ecological or environmental concerns. Legumes can provide opportunities for increased productivity to be sustained because of their adaptability to various cropping patterns and ability to fix nitrogen. Legume-based crop rotation helps to conserve organic matter, maximise soil nitrogen, balance soil nutrients, maintain soil physical properties and break soil-borne disease cycles. Moreover, with increasing fertilizer prices and emphasis of the government for doubling the farmer’s income by reducing cost of cultivation, the current trend is to explore the possibility of supplementing chemical fertilizer with the organic ones, more particularly organic manures and bio-fertilizer of microbial origin. The current study is aimed to increase small and marginal farmer’s income and to reduce cost of cultivation through legume based vegetable cropping systems and to find out best farming practices. Methods: Field experiments were conducted at Organic Farm Holta, Department of Organic Agriculture and Natural farming, CSK HPKV, Palampur (H.P.) during kharif and rabi seasons of 2018-19 and 2019-20 on silty clay loam soil to study the performance of different farming practices in legume based cropping system under mid- hills of H.P. Himalayas. The experiment was laid out under Split plot design with three replications comprising of three sequences in legume vegetable-based cropping systems i.e., “Soybean-Onion”, “Okra-Pea” and “Mash-Garlic” under different farming practices i.e., Organic farming, Natural farming, Inorganic and Integrated farming practices. For comparison of different crops soybean equivalent yield and pea equivalent yields were calculated in kharif and rabi seasons, respectively. Result: In kharif seasons okra crop attained highest soybean equivalent yield followed by soybean and mash crop. In rabi seasons garlic crop attained highest pea grain equivalent yield followed by onion and pea crop. During both kharif seasons organic farming practices attained highest yield and was at par with integrated farming practices. Significantly highest yield was attained from integrated farming practices and was at par with organic farming practices in both rabi seasons. Highest net returns, net returns per rupee attained was in inorganic farming system. Highest cost of cultivation was found in organic farming practices.

CO2, H2O and energy fluxes from chickpea crop grown under residual soil moisture condition in rainfed peninsular India using eddy covariance techniques

Present study is the first to report the ecosystem CO2, H2O and energy exchanges (at diurnal, daily and seasonal-scale) from rainfed winter chickpea crop (Cicer arietinum L.), grown under residual soil moisture over semi-arid peninsular India, using eddy covariance system. The available energy to the ecosystem was found to be predominantly partitioned into sensible heat flux (H), except during the peak vegetative stage. Asymmetric response of the daytime (forenoon and afternoon) CO2 and energy fluxes were observed due to limited soil moisture condition. The peak vegetative stage of the crop i.e., 40–60 Days after Sowing (DAS) showed highest rate of Net Ecosystem CO2 Exchange (NEE; −9 to −11 μmol m−2 s−1) and Latent Heat Flux (LE; ∼ 300 W m−2). The response of daytime Gross Primary Production (GPP) to light intensity was found to be poor during 1–16 DAS, improved steadily in 17−34 DAS, remained high in 35–69 DAS, and deteriorated thereafter till harvesting (70–106 DAS). The chickpea crop was net CO2 sink on daily basis during 17–69 DAS. Peak daily NEE of −2.52 gC m−2 day−1, GPP of 4.2 gC m−2 day-1 and Evapotranspiration (ET) of 2.38 mm day−1 were observed during the growing season. Over the entire season, rainfed chickpea was found to be a weak carbon sink with cumulative NEE of -32.39 ± 4.21 gC m−2; GPP of 163.03 ± 15.04 gC m−2; Ecosystem Respiration (Reco) of 127.45 ± 12.85 gC m−2; ET of 177 ± 18.13 mm. The maximum ecosystem water use efficiency (GPP/ET) and crop coefficient were found to be 1.7 gC m−2 mm−1 and 0.6 respectively at peak vegetative stage, which are sub-optimal compared to well managed chickpea crop. The results help us to understand the ecosystem processes and exchanges from rainfed winter legume-based cropping system, which intern would significantly contribute in global carbon and moisture budget.

​Conservation Agriculture Practices: Impact on Productivity, Energy Utilisation and Profitability of Legume-based Cropping System

Background: Conservation agriculture (CA), an agricultural production system with optimum inputs, high returns and sustainability while conserving environment is primarily required for command areas and rainfed uplands. CA helps to improve and conserve soil health through crop rotation, mulching, minimum field traffic and mechanical soil disturbance etc and conserve water to achieve economically and ecologically sustainable crop production. Methods: The field experiment was conducted for two years during 2019-21 to evaluate the influence of conservation agricultural practices on the system productivity, production efficiency and energy use under legume based cropping system in a command area. Treatments comprised of four cropping systems as Groundnut - foxtail millet (C1), Groundnut - barnyard millet (C2), Daincha - foxtail millet (C3) and Daincha - barn yard millet (C4) in main plots and foliar application of organics, 3% panchagavya, 1% PPFM and 0.1% humic acid formed subplots. Result: System productivity in terms of Groundnut equivalent yield (GEY) was significantly higher (8395 kg/ha) in the Groundnut - Barnyard millet cropping system with foliar application of PPFM 1% in CA system than that of conventional method. The production efficiency was maximum in Groundnut - barnyard millet system (34.41 kg/ha/day) and Groundnut - foxtail millet recorded the highest energy use efficiency (6.8%) which shows that maximum energy was effectively utilized under the system. Daincha - foxtail millet system had highest energy productivity of 0.91 kg M/J. Thus, the conservation tillage based Groundnut - barnyard millet system recorded more system productivity, highest resource use efficiency (both production and land use efficiency) and the highest energy use efficiency.

Grain legume-based cropping systems can mitigate greenhouse gas emissions from cereal under Mediterranean conditions

Legume-based cropping systems have been promoted as a sustainable alternative to fertilizer-based systems. However, the efficacy of this strategy for mitigating greenhouse gas (GHG) emissions in Mediterranean agroecosystems is still not well known. We conducted two field trials in Mediterranean conditions aiming to compare the soil nitrous oxide (N2O) and methane (CH4) emissions under rainfed triticale (× Triticosecale) monocropped with and without N fertilizer, or in rotation with rainfed faba bean (Vicia faba), rainfed pea (Pisum sativum), or summer-irrigated cowpea (Vigna unguiculata). The effect of incorporation vs. removal of the legume residues was also evaluated. Soil mineral N, moisture contents and GHG fluxes were measured throughout two consecutive years. Legume-based cultivation reduced triticale yield-scaled N2O emissions (YSNE) in a wet year but maintained or even increased YSNE in a dry year. This was mostly due to low N use efficiency (NUE) in the fertilizer-based systems and to favorable conditions for denitrification when rainfall was high. Significant differences in CH4 exchange between systems were only observed in the cowpea-triticale rotation with incorporated residues, which mitigated triticale CH4 emissions in the dry year, possibly due to improved soil aeration and reduced water stress to methanotrophs.We conclude that legume-based farming can be an effective GHG mitigation strategy in Mediterranean agroecosystems, but efficient supplementary N fertilization may be necessary to achieve a reduction in GHG emissions without compromising crop yields.

Will Phosphate Bio-Solubilization Stimulate Biological Nitrogen Fixation in Grain Legumes?

Biological nitrogen fixation (BNF) refers to a bacterially mediated process by which atmospheric N2is reduced, either symbiotically or non-symbiotically, into ammonia (NH3) in the presence of the enzyme complex nitrogenase. In N2-fixing grain legumes, BNF is often hampered under low phosphorus (P) availability. The P status of legumes, particularly nodules, as well as P availability in the rhizosphere, play a vital role in regulating BNF. Aside from increasing P availability via fertilization, other plant traits (i.e., extensive rooting system and their spatial distribution, hyper-nodulation, root exudates, rhizosphere acidification, and heterogeneity) contribute to greater P uptake and hence more effective BNF. The positive interaction between P availability and BNF can be exploited through beneficial soil P solubilizing microorganisms (PSM). These microorganisms can increase plant-available P by modifying either rhizosphere soil processes or promoting plant traits, which lead to increased P uptake by the production of plant growth-promoting substances, both of which could indirectly influence the efficiency of BNF in legumes. In this review, we report on the importance of microbial P bio-solubilization as a pathway for improving BNF in grain legumes via PSM and P solubilizing bacteria (PSB). Because BNF in legumes is a P-requiring agro-ecological process, the ability of soil PSB to synergize with the rhizobial strains is likely a key belowground process worth investigating for advanced research aiming to improve rhizosphere biological functions necessary for sustainable legume-based cropping systems.