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Soil-test crop response (STCR) approach is aiming to precise adjustment of fertilizers under varying soil-test values for targeted-yield, presently gaining recognitions for sustainable nutrient management. The study aimed to envisage the precision scale of STCR targeted-yield models in maize-lentil rotation in alkaline Fluvisol under sole-fertilizer and integrated nutrient management (with farmyard manure). Fertility-gradient, test-crop diagnostic, and validation trials were conducted following STCR technical program. Soil fertility gradient and variable fertilizer doses had caused a large variation in grain yield of maize (0.99–4.94 t ha−1, CV = 30%) and lentil (1.11–2.02 t ha−1, CV = 13%). Lentil had increased potential to utilize soil nutrient pools; in contrast, maize was highly responsive to fertlizer nutrients. Multivariate-regression analysis revealed that fertilizers N, P, and S had a strong and direct influence on maize yield; where fertilizer-P was the primary yield-determining variable for lentil. Both sole-fertilizer and integrated STCR-based treatments attained the targeted-yields in maize. However, STCR treatments could not attain the targeted-yields in lentil (17–29% deviation), but had yield advantage over the blanket recommended fertilizer dose. Hence, in tropical-alkaline soils, integrated STCR targeted-yield approach could be the sustainable nutrient management option(s) for improving the productivity of the maize-lentil system. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) is highly sensitive to land use change and helps in maintaining soil quality. Changes in soil fertility status, SOC dynamics, and carbon indices were studied in a four-year experiment with nine sets of food-fodder cropping systems (CS) and three resource conservation techniques like rainfed (RC1), life saving irrigation (RC2) and in-situ moisture conservation practices (RC3). Results showed that the CS5 [Tri-Specific Hybrid (TSH) + Desmanthus virgatus+ (Sorghum + Cowpea – Chickpea)] recorded the highest values 12.25 g kg−1, 41.5 mg kg−1, 3.5 g kg−1, 289.5 mg kg−1, 424.8 µg g−1 soil, 54.69% and 39.31% of total carbon (TC), hot water-soluble carbon (HWSC), particulate organic carbon (POC), labile carbon (LC), soil microbial biomass carbon (SMBC), humic acid carbon (HA-C) and fulvic acid carbon (FA-C), respectively. Among resources conservation practices, RC3 improved the SOC (56.16%) and other carbon fractions significantly as compared to RC1. Significant and positive correlations (P < 0.05) were found between carbon pools and available nutrients. The carbon management index (CMI) was also maximum (193) with CS5 and CS9 [TSH + Sesbania sesban+ (Sorghum + Cowpea – Barley)] and RC3 (232). Therefore, promoting cultivation of food-fodder system with in-situ moisture conservation practices is considered as sustainable management option for sequester more carbon, sustainability and soil quality in rainfed semi-arid ecosystem. [ABSTRACT FROM AUTHOR]

Sustainability of cereal-based cropping systems remains crucial for food security in South Asia. However, productivity of cereal–cereal rotations has declined in the long run, demonstrating the need for a sustainable alternative. Base crop, that is, common crop in different crop rotations, productivity could be used as a sustainability indicator for the assessment of different long-term crop rotations. This study aimed to evaluate the impact of grain legume inclusion in lowland rice–wheat (R-W) and upland maize–wheat (M-W) rotation on system's base crop (rice in lowland and wheat in upland crop rotations) productivity and sustainability and also in soil fertility. Mung bean (April–May) inclusion in R-W rotation increased rice grain yield by 10–14%. In upland, mung bean inclusion in M-W rotation increased wheat grain yield by 5–11%. Replacing wheat with chickpea in R-W rotation increased rice grain yield by 5–8%. Increased base crop productivity in legume inclusive rotations was attributed to significant improvement in panicle (rice) or spike (wheat) attributes. Increased soil organic carbon and available nitrogen and phosphorus in the legume inclusive rotations significantly influenced the base crop productivity in both the production systems. Among the crop rotations, R-W-Mb (in lowland) and M-W-Mb (in upland) rotations had the highest system productivity and net return. Therefore, intensification/diversification of cereal–cereal rotations with grain legume could improve soil fertility and sustain crop productivity. [ABSTRACT FROM AUTHOR]

A field experiment was conducted during the kharif (rainy) seasons of 2005-2006 to study the effect of eight composts prepared from four different types of plant biomass (rice straw (Oryza sativa), Eupatorium adhenophorum, Lantana camara and grass/weed mixtures) following two composting procedures: (i) Microbial Enriched Compost (MEC) [biomass + cow dung + compost culture (formulations of cellulose decomposers, P-solubilizing microbes and free-living N-fixers], and (ii) Microbial and Nutrient Fortified Compost (MNFC) [MEC + rock phosphate at 2.5% (w/w) + neem cake 1%] on productivity of lowland rice. Recommended NPK (80:60:40 kg ha-1) and farmyard manure (FYM) at 10t ha-1 (similar to compost dose) treatment were also kept for comparison. In general, the performance of rice under MNFC composts was superior to MEC composts. The results revealed that the grain yield of rice with rice straw MNFC compost and Eupatorium MNFC compost were 5% and 3% higher than recommended NPK, respectively. The nutrient uptake and post-harvest soil fertility status were also significantly higher under these treatments compared to recommend NPK. In the present study, although the increments in grain yield of rice with various composts were not much during two years experimentation, substantial improvement in soil fertility in terms of available NPK was observed. [ABSTRACT FROM AUTHOR]

Poor soil quality and low fertility are major limitations to agricultural intensification and increasing crop productivity under rainfed hill ecosystems of North Eastern Region (NER) of India. Intensive tillage and adoption of mono-cropping of rice ( Oryza sativa L.) or maize ( Zea mays L.) leads to depletion of soil fertility and crop productivity. A three year field experiment (2007–2010) was conducted at mid altitude of Meghalaya, India with eight cropping sequences [maize-rapeseed ( Brassica campestris L. var. toria.), maize-pea ( Pisum sativum L.), rice ( Oryza sativa L.)- rapeseed, rice-pea, ricebean ( Vigna umbellate Thunb.)-rapeseed, ricebean-pea, soybean ( Glycine max L. Merr) – rapeseed and soybean-pea] under two tillage systems; conservation tillage (CST) and conventional tillage (CT). The objectives were to assess impact of tillage and cropping sequence(s) on soil quality and fertility after three years of the experiment. Soil moisture content and infiltration rate were significantly improved under CST relative to those under CT. The soil organic carbon (SOC) concentration was significantly higher under CST (23 g/kg) relative to that under CT (21.2 g/kg) at 0–15 cm soil depth. Available nitrogen (N), phosphorous and potassium, soil microbial biomass carbon (SMBC) and dehydrogenase activity (DHA) were also significantly higher in CST than those under CT. The cropping sequences did not affect the bulk density (ρ b ) and SOC significantly. However, available N, SMBC and DHA concentration were significantly higher under soybean-pea and soybean-rapeseed sequences as compared to others. During 2009–10, where rainfall received during the winter season was negligible, 4–70% higher yields of winter crops were observed under CST than those under CT. Thus, adoption of CST and soybean based cropping sequences offers an alternative to raise crops during the winter season on residual soil moisture and improve soil quality in eastern Himalayas. [ABSTRACT FROM AUTHOR]