Sustainable Crop Yield Research Articles

Nitrogen application increases soil respiration but decreases temperature sensitivity: Combined effects of crop and soil properties in a semiarid agroecosystem

Nitrogen (N) fertilization has been repeatedly reported to strongly influence soil properties and crop growth. However, there is little information about the combined effects of soils and crops on soil CO2 fluxes under N fertilization. In this study, in situ soil respiration, soil physicochemical properties, microbial communities and crop properties were measured for eight years (2008 to 2016) on the Loess Plateau. Five rates of N fertilization were applied to different plots to compare the soil respiration rate and its temperature sensitivity (Q10). Nitrogen fertilization significantly increased mean annual cumulative soil respiration (Rcum) by 25%–44%. Rcum had a positive correlation with grain yield, and the carbon emission efficiency (grain yield produced per unit of carbon emission) under N-fertilized plots was 1.62–2.52 times that of unfertilized plots. Rcum also had a positive correlation with root biomass and the root N concentration but showed a negative correlation with the root C/N ratio. The Q10 values under N-fertilized plots decreased by half at a diurnal scale, but had a smaller reduction (i.e., 0.04–0.09) at an annual scale compared to unfertilized plots. The decreased Q10 values under N-fertilized plots also resulted from the lower aromaticity of dissolved carbon (SUVA254) (7.40 vs. 10.53 L mg C−1 m−1). In addition, the altered Rcum and Q10 values were affected by the varied bacteria community derived from N fertilization, which was related to Acidobacteria, Chloroflexi, Proteobacteria and Bacteroidetes. Therefore, N fertilizer applications regulate the combined effects of soil and crop parameters on soil respiration and the Q10 value. This study suggests that, due to the lower carbon emission efficiency and higher SOC concentration under N-fertilized plots, N fertilizer applications may be used to sustain crop yields and increasing SOC storage while minimizing carbon emission impacts to the environment on the Loess Plateau.

Can Potassium Silicate Mineral Products Replace Conventional Potassium Fertilizers in Rice–Wheat Rotation?

Core Ideas We assessed the effects of several mineral fertilizers on crop yield and soil potassium fertility.The mineral fertilizers could maintain crop yield and soil potassium fertility.The mineral fertilizers could increase soil pH.The mineral fertilizers can partly replace conventional potassium fertilizers. Potassium (K) silicate minerals are important insoluble K resources and exploring their potential as alternatives to conventional K fertilizers would be helpful to deal with the widespread K deficiency in the world. Thus on‐farm experiments with potassium silicate mineral products (KSMPs), e.g., Fubang (FB), Zhongke (ZK), Ziguang (ZG)—manufactured from natural K‐bearing rocks—were conducted to investigate their effects on crop yield, soil K fertility and pH in rice‐wheat (Oryza sativa L.–Triticum aestivum L.) rotation at Guangde County and Jiangdu County, China. The experiments lasted 2 yr at two sites and six treatments about K fertilizers were tested: no K fertilization (CK); 100% K chloride (KCl); 100% ZG; 50% KCl +50% ZG; 50% KCl +50% FB; 50% KCl +50% ZK. Results showed that both wheat and rice grain yields for CK were markedly decreased compared with that for the other treatments, regardless of K fertilizer types. Similar to KCl, the KSMPs could maintain crop yields and soil potassium fertility. Besides, the KSMPs significantly improved soil pH by average 0.47 and 0.38 at Guangde and Jiangdu, respectively, compared with that for KCl, after its application for 2 yr. However, the apparent K balances for most treatments at two sites were negative. In terms of economic aspect, the value cost ratio averaged by sites of ZG was 2.59 which was significantly higher than that for FB and ZK. In conclusion, the KSMPs can sustain crop yields and soil K fertility and thus can partly substitute conventional K fertilizers in rice‐wheat rotation on the Aquic Haplanthrepts soils.

Performance of green manuring for soil health and crop yield improvement

Intensive cultivation, low and imbalance use of fertilizers, soils are continuously depleted and degraded. Green manuring (GM) is a well-known practice performed by the farming communities almost around the globe. Green manure crops are grown and ploughed as green foliage to improve soil characteristics. Leguminous crops have more importance as green manure over non- leguminous crops. Green manuring is one of the important possible options in achieving the ultimate goal of sustainable crop yield improvement. Various studies have highlighted the role of green manuring in improving soil organic matter, soil porosity, water holding capacity and soil C: N ratio. Fertilizer use efficiency (FUE) is improved by incorporation of green manure crops. It is helpful in sustainable agriculture systems by maximizing the crop yields and improving the livelihood of farming community. High yielding varieties are being introduced at a rapid pace to meet up the current challenges related to food security. Therefore, integrated use of green manuring and fertilizers is the best combination for achieving higher yield. Inclusion of green manure crops in the exiting cropping system has some constraints like availability of quality seed to farmers, performance variability in green manure crops, problems related to its establishment and incorporation as well. Moreover, costly tillage, seeding operations and labor need to be reduced for better adoption of green manure programme. The sole objective of this article was to review the advances in green manuring technology. Keywords: FUE; Green manuring; Legume crops; Limitations; Profitability; Soil health http://dx.doi.org/10.19045/bspab.2019.80095

Effects of tillage managements and maize straw returning on soil microbiome using 16S rDNA sequencing.

Agricultural practices could affect bacterial diversity and community structure by altering soil physical and chemical properties. Straw returning and tillage practices are widely used in agriculture, however, the effects of these agricultural practices on microbiomes are still unclear. In the present study, we compared the 18 bacterial communities of soil with different straw returning and tillage treatment combinations. The V3-V4 regions of the 16S ribosomal RNA were amplified and analyzed by high-throughput sequencing technology. The results showed that the bacterial communities were consistently dominated by Acidobacteria, Proteobacteria, Actinobacteria, and Chloroflexi. Short-term straw returning and tillage practices significantly altered the diversity, relative abundance and functions of the soil microbiome. Soil subjected to rotary tillage and straw returning (RTS) combination possessed the highest bacterial diversity and lowest ratio of G+/G- bacteria, indicating that RTS could be an efficient integrated management system to improve microbiome in the short term. Double verifications based on relative abundance and network analysis, revealed close relationships of Mycobacterium and Methylibium with RTS, indicating they could serve as biomarkers for RTS. Investigating microbial changes under different agricultural practices will provide valuable foundations for land sustainable utilization and increase crop yields.

Effects of tillage and straw return on water-stable aggregates, carbon stabilization and crop yield in an estuarine alluvial soil

In China, the average soil organic carbon (SOC) content of cultivated land is 30% less than the world average. Therefore, cultivation management-induced changes in SOC dynamics are necessary, especially in estuarine alluvial islands, where the SOC stocks are limited. We studied the effect of different combinations of tillage, fertilization and straw return on C distribution in different soil aggregates and on crop yield on an estuarine alluvial soil in eastern China. Compared to conventional tillage, conservation tillage (no-tillage coupled with straw return) increased water-stable large macroaggregates (>2 mm) by 35.18%, small macroaggregates (2–0.25 mm) by 33.52% and microaggregates by 25.10% in the topsoil (0–20 cm). The subsoil (20–40 cm) also showed the same trend. Compared to conventional tillage without straw return, large and, small macroaggregates and microaggregates in conservation tillage were increased by 24.52%, 28.48% and 18.12%, respectively. Straw return also caused a significant increase in aggregate-associated carbon (aggregate-associated C). No-tillage coupled with straw return had more total aggregate-associated C within all the aggregate fractions in the topsoil. But the different is that conventional tillage with straw return resulted in more aggregate-associated C than conservation tillage in the subsoil. No-tillage combined with straw return (T8) produced the highest carbon preservation capacity (CPC) of macroaggregates and microaggregates in the topsoil. A considerable proportion of the SOC was found to be stocked in the small macroaggregates under both topsoil (74.56%) and subsoil (67.09%). The CPC was highest (19.17 g·kg−1) in small macroaggregates. However, no-tillage and straw return had less potential to sustain crop yield than did the conventional tillage practices; with the average rice and wheat yield correspondingly decreased by 10.63% and 7.82% in three years.

Long Term Fertilizer Management Effect on Nutrient Dynamics in Rainfed Rice-lentil System in Transect 4 of IndoGangetic Plain

The present study analyzed the effect of different organic and inorganic fertilizers on soil nutrient dynamics in a long-term field experiment under rainfed rice-lentil system. The experiment was operative at Agricultural Research Farm, Institute of Agricultural Sciences, B.H.U Varanasi, Uttar Pradesh, India. Carbon dynamics was investigated on surface soil on the basis of distribution of Walkley & Black Carbon, in active pool (AP) or labile carbon (oxidisable at low concentration of H2SO4) in relation to passive pool (PP) or non labile carbon (oxidisable at high concentration of H2SO4) and its indices carbon management index (CMI). The effect of eight different treatments including unfertilized, 100% N from farm yard manure, 100% recommended dose of fertilizer, 50% RDF + 50% N Foliar), 50% RDF, 50% RDF + 50% N FYM), 50% N FYM and Farmers practices i.e. application of 20kg N ha-1 The availability & uptake of major nutrients were studied. The results revealed: That mixed application of inorganic fertilizers and FYM substantially increase the soil organic carbon pool, sustainability index over remaining treatments. Higher fertilizer application rates resulted in higher and sustained crop yields which had been reflected in sustainability yield index. A significant Pearson correlation was found between SOC, AP, PP, exchangeable K2O content, soil microbial biomass carbon and SYI. (The result indicated to adopt conjunctive use of nutrient management which promote the SOC more labile and, induce availability of other nutrients coupled with SMBC that translate into higher crop yields.

Pea Growth, Yield, and Quality in Different Crop Rotations and Cultural Practices

Core Ideas Management strategies are lacking to enhance dryland pea growth, yield, and quality. Pea yield and quality were studied in various crop rotations and cultural practices. Pea yield and N uptake were greater with alternate‐year than stacked crop rotation. Stand count was greater with the improved than the traditional cultural practice. Alternate‐year rotation and improved cultural practice enhanced pea yield and quality. Dryland pea (Pisum sativum L.) is an important pulse crop that can replace fallow or be added to existing crop rotations to sustain crop yields in arid and semiarid regions. Yet, we lack management practices to enhance yield and quality of dryland pea. This study evaluated the effect of crop rotation and cultural practices on dryland pea growth, yield, and quality from 2006 to 2011 in the northern Great Plains, USA. Stacked rotations were durum (Triticum turgidum L.)–durum–canola (Brassica napus L.)–pea (DDCP) and durum–durum–flax (Linum usitatissimum L.)–pea (DDFP), and alternate‐year rotations were durum–canola–durum–pea (DCDP) and durum–flax–durum–pea (DFDP). Traditional cultural practice included a combination of conventional till, recommended seed rate, broadcast N fertilization, and reduced stubble height, and improved cultural practice a combination of no‐till, increased seed rate, banded N fertilization, and increased stubble height. Pea pod number, plant height, grain yield, and N uptake were 4 to 18% greater with DCDP and DDCP than other rotations. Improved cultural practice increased stand count by 29% over traditional cultural practice. Biomass yield, N uptake, and grain protein concentration varied with crop rotations and cultural practices in various years. Seed number, seed weight, harvest index, and N harvest index were not influenced by treatments. Pea yield and N uptake increased with alternate‐year rotation due to increased pod number and plant height. Stand count increased with improved cultural practice. Alternate‐year crop rotations and improved cultural practice enhanced dryland pea yield and quality.

Conservation agriculture for productivity and profitability of wheat and lentil in maize based cropping system in far western Nepal

Zero tillage with crop residue retention which is principle of conservation agriculture (CA) can be a good practice to achieve sustainable and profitable crop yield without affecting soil fertility. This approach was not tested in wheat and lentil based maize-mungbean system in far western Nepal. The effect of CA in the maize-wheat-mungbean and maize-lentil-mungbean cropping systems with two varieties of each of wheat and lentil was studied at Regional Agricultural Research Station, Bhagetada, Dipayal, Doti district of Nepal for two years (2015 and 2016). The average grain yield of wheat and lentil under the CA system was 5.92% higher (2.86 t ha−1) than that of conventional agriculture (2.70 t ha−1). The CA under maize-wheat-mungbean cropping system produced 7.90% higher grain yield (4.78 t ha−1) compared to conventional agriculture and the CA under maize-lentil-mung bean cropping system gave11.11% higher grain yield (1.00 t ha−1). Maize-wheat-mungbean cropping system, conservation agriculture and WK 1204 variety of wheat produced 9.34% higher yield (4.80 t ha−1) than conventional agriculture whereas maize-lentil-mungbean cropping system, conservation agriculture and Khajura1 variety of lentil recorded 11.96% higher grain yield (1.03 t ha−1) than conventional agricultural. The CA system produced 114% higher net benefit (NRs. 40200 ha−1) than that of conventional agriculture. Higher yields of crops in CA system could be associated with improvement of soil properties for minimum soil disturbance and residue retention and profitable yield for reduced cost of production. Thus, the 2-year study suggests that no tillage with previous crop residues retention and use of higher yielding varieties is a potential crop cultivation approach for the maize based cropping system in light textured soil of river basin area of Nepal in order to sustain soil health, crop yield and farm economy.
 J. Bangladesh Agril. Univ. 16(3): 403–410, December 2018

Agricultural history nexus food security and policy framework in Tanzania

BackgroundUnderstanding the production trend of the major food crops is an important step for any nation that evaluates her agricultural progress. This evaluation should mostly focus on the yields per unit area. So far, it can also earmark the expansion of farms to determine the general yields trend. The main objective of this paper is to assess the production trend of the major food crops and their efficacy to food security in Tanzania. This is particular important because for the past three decades, the country has failed to control food security (especially food availability and accessibility).ResultsHere, crop data from 1980 to 2015 were gathered from the Ministry of Agriculture, Livestock and Fishery (MALF), and in the respective regions. In some incidences, the regional data were averaged to elicit their preciseness. To determine the objectivity of this study, agricultural policy, programs, and plans from MALF were reviewed for similar purpose. Mostly, the Mann-Kendal Test and Microsoft Excel were used for data analyses. The results show that the production of the total yields had a positive trend (i.e., growing at R2 = 0.4 and 0.8), while that of the yields (ton/ha) had a negative trend (i.e., declining at R2 = 0.02 and 0.3). It was further realized that the total yields mostly boomed due to farm expansion.ConclusionsDespite the efforts from various agricultural stakeholders, the country has not yet achieved a sustainable crop yield and food security. Explicitly, this situation has been affecting peoples’ livelihoods, and other sectors either directly or indirectly. Therefore, there is a need to improve the production strategies and approaches (i.e., more especially technology and marketing) to limit this problem.

Effects of organic substitution for synthetic N fertilizer on soil bacterial diversity and community composition: A 10-year field trial in a tea plantation

Substitution of chemical nitrogen (N) with organic fertilizers in agricultural ecosystems has been promoted to sustain crop yield and soil quality. Soil microbes play key roles in soil nutrient cycling after organic matter addition. However, there is limited information about the effect of the organic substitution ratio (OSR) on soil bacterial communities, which are considered as a good indicator of soil quality in a tea plantation. In this study, a long-term field experiment with six treatments was established to study the effect of different OSRs of N, from pure synthetic fertilization (NPK) to 100% N substituted with organic fertilizer (OM100), on tea yield and soil bacterial communities. The soil bacterial community composition was measured using a high-throughput sequencing technique. The results showed that as the OSR increased, the soil bacterial diversity increased and the community structure shifted significantly. However, 25% N substituted with organic fertilizer (OM25) produced the highest yield. Additionally, the soil pH and organic carbon (SOC) were the predominant soil characteristics that accounted for the soil bacterial community structural change. With more chemical N being substituted with organic fertilizer, the soil pH, available potassium, SOC, total N, and microbial biomass C and N, were elevated; however, the yield of fresh tea leaves decreased. These results indicated the trade-off effect between tea yield and soil bacterial diversity under different OSRs, which could also alter the soil bacterial communities by changing soil characteristics.

Prediction of Soil Moisture-Holding Capacity with Support Vector Machines in Dry Subhumid Tropics

Soil moisture-holding capacity data are required in modelling agrohydrological functions of dry subhumid environments for sustainable crop yields. However, they are hardly sufficient and costly to measure. Mathematical models called pedotransfer functions (PTFs) that use soil physicochemical properties as inputs to estimate soil moisture-holding capacity are an attractive alternative but limited by specificity to pedoenvironments and regression methods. This study explored the support vector machines method in the development of PTFs (SVR-PTFs) for dry subhumid tropics. Comparison with the multiple linear regression method (MLR-PTFs) was done using a soil dataset containing 296 samples of measured moisture content and soil physicochemical properties. Developed SVR-PTFs have a tendency to underestimate moisture content with the root-mean-square error between 0.037 and 0.042 cm3·cm−3 and coefficients of determination (R2) between 56.2% and 67.9%. The SVR-PTFs were marginally better than MLR-PTFs and had better accuracy than published SVR-PTFs. It is held that the adoption of the linear kernel in the calibration process of SVR-PTFs influenced their performance.

Harvest optimization to assess sustainable growth and carrageenan yield of cultivated Kappaphycus alvarezii (Doty) Doty in Indian waters

Kappaphycus alvarezii (Doty) Doty, a carrageenan yielding red seaweed, was cultivated for a period of 1 year from April 2012 to March 2013 at Munaikadu in Palkbay waters of Bay of Bengal, Southeast coast of India. The experiments aimed to assess the ideal period for harvest among the different growth periods (15, 30, 45, 60, and 90 days) adopted to achieve sustainable growth (biomass yield or crop yield) as well as carrageenan (semi-refined carrageenan—SRC) content. Almost similar (higher) productivities and SRC yields with quality were obtained during 45 and 60 days growth periods. However, the income was more in 45 days (Rs.70708/-, US$ 1122.35) than in 60 days (Rs. 56,396/-, US$ 895.17) growth period. Considering productivity, total dry weed output, total revenue and net revenue per year, profit margin, carrageenan content, CAW content, and gel strength, 45 days growth period was found to be ideal among the different growth periods (15, 30, 45, 60, and 90 days). If the growers follow strictly 45 days growth cycle, they will benefit more and buyers will not be much affected. This study envisages that entrepreneurs and non-governmental organizations (NGOs) should raise awareness among growers for strictly enforcing 45 days growth period for commercial cultivation to obtain a sustainable crop yield with quality SRC.

Vine and citrus mealybug pest control based on synthetic chemicals. A review

Synthetic chemicals are extensively used to limit the substantial crop damage induced by two closely related scale insects, the vine mealybug Planococcus ficus (Signoret) and the citrus mealybug Planococcus citri Risso (Hemiptera: Pseudococcidae). Both organisms are economically important pests occurring in vineyards and/or in citrus orchards worldwide. Synthetic chemicals can be either incorporated in pesticides aimed at directly controlling these pests or used as semiochemicals (i.e., sex pheromones) for monitoring, mass trapping, mating disruption, and/or for kairomonal attraction to enhance parasitoid performances. Growing evidence of both an alarming bee decline and destruction of auxiliary fauna driven by pesticides have stimulated an urgent need for in-depth research clarifying the adverse side effects of pesticides on beneficial arthropods. We have reviewed the current knowledge on mealybug pest control based on insecticides and semiochemicals. We highlight the following major advances: (1) How the active substances of insecticides (four organophosphates, imidacloprid, buprofezin, and spirotetramat) affect target and non-target organisms, (2) in which contexts and how a semiochemical-based strategy could be applied to deal with serious mealybug infestations, and (3) the implications of the appropriate exploitation of these synthetic chemicals for sustainable development. Using selective insecticides with novel modes of action and long-lasting efficacy in combination with eco-friendly semiochemical-based tools is a promising strategy for developing sustainable integrated pest management programs. This would help to maintain biodiversity dynamics and vital ecosystem services, thereby sustaining crop yields.

Crop yield and soil properties of dryland winter wheat-spring maize rotation in response to 10-year fertilization and conservation tillage practices on the Loess Plateau

Drought and nutrient deficiency are the principal factors limiting crop production in arid and semi-arid areas. Conservation tillage can maintain and increase grain yields by enhancing soil fertility and conserving more soil water in the field. However, farmers without access to mineral fertilizers cannot compensate for the soil nutrient deficiencies for crop production, and the crops will suffer yield reductions. Site-specific fertilizer application with conservation tillage practice management is the key to achieving a high and sustainable crop yield. A long-term (2007–2016) two-factor, spilt-plot experiment was established to assess the effects of fertilization {balanced fertilization (BF), low fertilization (LF), conventional fertilization (CF)} and conservation tillage practices {no tillage (NT), subsoiling (ST), conventional tillage (CT)} on grain yield, soil water and soil nutrients. The aim of this experiment was to select an optimal fertilization and tillage management system for crop production in the Loess Plateau, a typical semi-arid and rainfed area of China. Ten-year data showed that subsoiling with balanced fertilization (BST) increased the grain (6465 kg ha−1) and straw yield (9792 kg ha−1), but no tillage with balanced fertilization (BNT) was observed to provide the highest economic profit for farmers (6416 yuan ha-1). No tillage with low fertilization (LNT) was the optimal management for soil water conservation in fields that could preserve more soil water in fallow land (mean value: 425 mm) and provide more soil water during the wheat (mean value: 387 mm) and maize (mean value: 420 mm) growth season. The LNT consumed less soil water in the crop growth season (mean value: 105.4 mm), but the BST (18.5 kg ha−1 mm−1) showed a higher water use efficiency (WUE). The BF and NT showed better soil nutrient conditions (soil organic matter(SOM), available N, P and K) over the ten years and provided better soil water and balanced soil nutrient conditions for crop growth. The BNT and BST were recommended as the optimal and economic fertilization with tillage management systems for maintaining high grain yields by using soil water efficiently and enhancing soil fertility in a winter wheat-spring maize rotation on the Loess Plateau.

Global analysis of threonine metabolism genes unravel key players in rice to improve the abiotic stress tolerance

The diversity in plant metabolites with improved phytonutrients is essential to achieve global food security and sustainable crop yield. Our study using computational metabolomics genome wide association study (cmGWAS) reports on a comprehensive profiling of threonine (Thr) metabolite in rice. Sixteen abiotic stress responsive (AbSR) – Thr metabolite producing genes (ThrMPG), modulate metabolite levels and play a significant role determining both physiological and nutritional importance of rice. These AbSR-ThrMPG were computationally analysed for their protein properties using OryzaCyc through plant metabolic network analyser. A total of 1373 and 1028 SNPs were involved in complex traits and genomic variations. Comparative mapping of AbSR-ThrMPG revealed the chromosomal colinearity with C4 grass species. Further, computational expression pattern of these genes predicted a differential expression profiling in diverse developmental tissues. Protein interaction of protein coding gene sequences revealed that the abiotic stresses (AbS) are multigenic in nature. In silico expression of AbSR-ThrMPG determined the putative involvement in response to individual AbS. This is the first comprehensive genome wide study reporting on AbSR –ThrMPG analysis in rice. The results of this study provide a pivotal resource for further functional investigation of these key genes in the vital areas of manipulating AbS signaling in rice improvement.

Potentials to mitigate greenhouse gas emissions from Swiss agriculture

There is an urgent need to identify and evaluate management practices for their biophysical potential to maintain productivity under climate change while mitigating greenhouse gas (GHG) emissions from individual cropping systems under specific pedo-climatic conditions. Here, we examined, through DayCent modeling, the long-term impact of soil management practices and their interactions on soil GHG emissions and GHG intensity from Swiss cropping systems. Based on experimental data from four long-term experimental sites in Switzerland (Therwil, Frick, Changins, and Reckenholz), we robustly parameterized and evaluated the model for simulating crop productivity, soil C dynamics and soil N2O emissions across a range of management practices and pedo-climatic conditions. Net soil GHG emissions (NSGHGE) were derived from changes in soil C, N2O emissions and CH4 oxidation. Soils under conventional management acted as a net source of soil GHG emissions (1361–1792 kg CO2eq ha−1 yr−1) and NSGHGE were dominated by N2O (50–63%). Reduced tillage and no-tillage reduced long-term NSGHGE by up to 31 and 58%, respectively. Organic farming, represented by organic fertilization, reduced NSGHGE by up to 31% compared to systems based solely on mineral fertilization. Replacement of slurries with a composted FYM led to an additional reduction in NSGHGE by 46%, although our approach considered only soil GHG emissions and thus did not take into account GHG emissions from the composting process. Cover cropping did not significantly influence NSGHGE, however vetch tended to reduce NSGHGE (-19%). The highest mitigation potential was associated with organic farming plus reduced tillage management, it reduced long-term NSGHGE by up to 128%. Soil C sequestration accounted, on average, for 89% of GHG mitigation potentials, consequently N2O dominated NSGHGE across all treatments and sites (60 − 80%). This indicates that these mitigation potentials are time limited and reversible, if the management is not maintained, in contrast to the reduction in N2O emissions, which is considered permanent. Not all the management practices sustained crop yields. Nevertheless, composting of organic manures, reduced tillage and no-tillage effectively reduced NSGHGE and GHG intensity without a noticeable yield reduction. Our results suggest that implementation of the above soil management practices in Swiss cropping systems have a considerable potential for climate change mitigation, although time-limited.

Enhancing Water and Phosphorus Use Efficiency Through Moisture Conservation Practices and Optimum Phosphorus Application in Rainfed Maize–Chickpea System in Vertisols of Central India

Conserving soil moisture in the rainfed region is a challenging task as it plays a significant role in crop productivity and livelihood security of rainfed farmers. The soil moisture conservation practices (MCPs) coupled with the addition of root augmenting nutrition are crucial for sustaining crop yields and maintaining soil phosphorus (P) in a rainfed Vertisol of Central India. Thus, a study was conducted to evaluate the long-term effect of MCPs and P application in maize–chickpea in a Vertisol. A five-year study showed that the MCPs integrated with P nutrition significantly helped in growing chickpea (Cicer arietinum) without irrigation or with limited irrigation. Under the normal rainfall conditions such as normal onset time, distribution and cessation time during the experimentation, the MCPs proved useful in obtaining chickpea yields in the range of 776 to 933 kg ha−1. The best MCP was the practice of late intercultural operations + Gliricidia cover in the inter-row spaces of standing maize (@ 5 t ha−1 fresh weight basis) + maize stover application (after sowing up to germination), which recorded higher chickpea grain yield (932 kg ha−1) on account of higher moisture content in the soil and reduced stress in the plants. Another comparable treatment was Gliricidia cover + one pre-sowing irrigation of 6 cm for chickpea, which recorded 933 kg ha−1 of chickpea yield. Both the treatments recorded significantly higher yields than the under control (637 kg ha−1). We also found that the application of Gliricidia cover on the soil surface coupled with either pre-sowing irrigation and/or late intercultural operations had beneficial effect on soil physical conditions increasing soil moisture which in turn affected the crop growth. Under normal monsoon years, the best treatments (MCP4 and MCP5) recorded around 46% higher chickpea yield as compared to the control. It is concluded that these soil MCPs are very useful in rainfed areas for sustaining crop yield.

Integrated use of manure and fertilizers increases rice yield, nutrient uptake and soil fertility in the boro-fallow-t.aman rice cropping pattern

The effect of integrated use of manure and fertilizers on crop yield, nutrient uptake and soil fertility was studied in the Boro-fallow-T. Aman cropping pattern over two years. The experiment was set up at Bangladesh Agricultural University (BAU) farm, Mymensingh under the AEZ 9 (Old Brahmaputra Floodplain). The field trial consisted of eight treatments and control (no fertilizer or manure), 100% chemical fertilizers (CF), and IPNS based six treatments with six types of manure. Cowdung (CD), CD slurry, Trichocompost (TC) and vermicompost (VC) were added to soil at 5 t ha-1 and poultry manure (PM) and PM slurry applied at 3 t ha-1. For all IPNS treatments, nutrient supply from manure was adjusted with that from chemical fertilizers. In each crop cycle, manure was applied to the first crop (Boro rice) and the residual effect was evaluated on the succeeding crop (T.Aman rice). The IPNS based treatments significantly increased the grain and straw yields of Boro rice and it had also positive residual effect on T.Aman rice. Trichocompost and vermicompost, among the six IPNS treatments, demonstrated higher crop yield and that was followed by poultry manure slurry and cowdung slurry. Integrated use of manure with fertilizers gave on an average 8.3-33.8% and 2.9-18.3% higher grain yield in Boro and T. Aman rice, respectively over sole fertilizers treatment. Higher nutrient uptake by crops (N, P, K & S) was also observed in IPNS treated plots. The IPNS treatments improved soil fertility in terms of increasing organic matter, N, P and S contents of soil after two crop cycles. The study suggests that manure and fertilizers should be used in an integrated manner to achieve sustainable crop yield, without incurring loss to soil fertility.SAARC J. Agri., 15(2): 147-161 (2017)

Instability and Sustainability Analysis of Mustard in Bhind (Madhya Pradesh) and Relationship with Factors of Production on Productivity

The oilseed crops play a crucial role in Indian agricultural economy. The oil content varies from 37 to 49 percent. Oil is utilized for human consumption, seeds as spices and cake as a cattle feed and manure. Mustard is also an important oilseed crop containing over 40 percent oil on a dry weight basis. Madhya Pradesh (MP) is the fourth major mustard producing the state in India followed by Gujarat and West Bengal, with a share of nearly 11 percent of the country's total mustard production. In present study sustainable growth in the area, production and yield of mustard during the period under investigation for whole Madhya Pradesh. While Madhya Pradesh is found sustainable in the area, production and productivity as compared to Bhind district, which is a witness that Bhind district is having more fluctuation in the area, production and productivity of mustard during the study under investigation. Hence, in recent years a concept of sustainable agriculture is developed in order to ensure that the agro-eco-systems are stabilized and sustained crop yields are assured on a long term basis.

Quantifying the Limitation to World Cereal Production Due To Soil Phosphorus Status

AbstractPhosphorus (P) is an essential element for plant growth. Low P availability in soils is likely to limit crop yields in many parts of the world, but this effect has never been quantified at the global scale by process‐based models. Here we attempt to estimate P limitation in three major cereals worldwide for the year 2000 by combining information on soil P distribution in croplands and a generic crop model, while accounting for the nature of soil‐plant P transport. As a global average, the diffusion‐limited soil P supply meets the crop's P demand corresponding to the climatic yield potential, due to the legacy soil P in highly fertilized areas. However, when focusing on the spatial distribution of P supply versus demand, we found strong limitation in regions like North and South America, Africa, and Eastern Europe. Averaged over grid cells where P supply is lower than demand, the global yield gap due to soil P is estimated at 22, 55, and 26% in winter wheat, maize, and rice. Assuming that a fraction (20%) of the annual P applied in fertilizers is directly available to the plant, the global P yield gap lowers by only 5–10%, underlying the importance of the existing soil P supply in sustaining crop yields. The study offers a base for exploring P limitation in crops worldwide but with certain limitations remaining. These could be better accounted for by describing the agricultural P cycle with a fully coupled and mechanistic soil‐crop model.