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Present field experiment was conducted at the Indian Institute of Soil Science, Bhopal on a clayey soil (Typic Haplusterts) during 2012–13 and 2013–14. The performance of soybean (Glycine max, cv. JS 335)–wheat (Triticum durum, cv. HI 8498) cropping system in terms of yield, nutrient uptake and economics under different organic and inorganic nutrient was assessed. The experiment was laid out in a randomized block design with seven treatments in four replications. The treatments involved different nutrient inputs viz. organic manure (OM) (T1); biodynamic preparation (BD) (T2); OM + panchagavya (OM + PG) (T3); OM + BD (T4); OM + PG + BD (T5); control (T6); and recommended dose of fertilizers (RDF) (T7). Cattle dung manure on N equivalent basis to soybean in kharif and cattle dung manure (CDM) + vermicompost (VC) + poultry manure (PM) (1:1:1 on N equivalent basis) to wheat were applied as organic manure whereas nutrients were supplied in the form of chemical fertilizers in RDF treatment. The yield of soybean and wheat crops obtained with organic combinations were found comparable and even better (5–13% higher) with those obtained under RDF which enhanced nutrient removal by soybean and wheat crops. The soybean–wheat sequence registered an increment of 2–11% and 11–26% in total N and P uptake, respectively over RDF. The net returns obtained under organic treatments were found statistically at par with those obtained under RDF. [ABSTRACT FROM AUTHOR]

Sustaining soil fertility and enhancing food production on smallholder farms is a great challenge in the Indo-Gangetic plains (IGP). Soil fertility parameters viz., physical, chemical and biological, though intrinsically linked to one another in the soil environment, are often studied in isolation. This work adds value to analyses of all these three components of soil quality influenced by different cropping systems under organic and chemical farming by correlating all these parameters, otherwise left unexplored. The study compared soil physical, chemical and biological characteristics in relation to long term organic and chemical farming in a sandy loam soil. The field experiments were conducted at Punjab Agricultural University, Ludhiana, India, with two farming systems in main plots for 12 seasons and four cropping systems in sub-plots for 4 seasons. The organic farming with green manuring (GM) to basmati rice and farmyard manure to wheat in basmati rice - wheat cropping system significantly increased soil water holding capacity, mean weight diameter, soil organic carbon, cation exchange capacity, dehydrogenase activity and basal soil respiration by 42.3, 62.7, 48.9, 59.0, 55.6 and 50.3%, respectively than with chemical farming. The crop productivity was 33.9% higher in organic than chemical farming, resulting in higher net returns under GM based organic farming. Principal component analysis (PCA) distincted organic farming from the chemical farming under different cropping systems based on basal soil respiration and cation exchange capacity in PC1 (explaining 93.1% of total variability), and the carbohydrate carbon and pH in PC2 (19.5% variability). These indicators are most influential for studying soil quality under organic farming and GM based cropping systems. [ABSTRACT FROM AUTHOR]

The major constraint in the promotion of organic farming, a safe and sustainable alternative, is lack of availability of quality organic resources in sufficient quantities. The quality of resources can be ascertained by monitoring its nutrient release pattern, which has not yet been attempted. A controlled condition pot experiment was conducted at ICAR-Central Tuber Crops Research Institute, Thiruvananthapuram, India, in completely randomized design to study the nutrient dynamics of various organic and inorganic resources, commonly used in cassava production, at monthly intervals up to six months. The release of almost all nutrients and activity of soil enzymes were higher at the middle (3 or 4 months) of the incubation period. The pH showed an increasing trend and electrical conductivity, organic C and Fe content declined from initial. Averaging over stages, organic practice favored the activity of soil enzymes and release of almost all nutrients over conventional system significantly, except N. [ABSTRACT FROM AUTHOR]