ABSTRACT
Low crop yields due to constant monocropping systems and deteriorating soil health in a smallholder farmers’ field of Indo-Gangetic plains of India have led to a quest for sustainable production practices with greater resource use efficiencies. The aim of the study was to elucidate the short term effects of conservation agricultural systems on productivity, soil health and carbon sequestration rate of soils in three different diversified cropping systems. The treatments consisted of two different tillage systems (conventional and reduced tillage), two mulch levels (no and straw mulch) and two levels of fertility (100 and 75% RDF) were compared in three rice-based cropping systems (rice-wheat; rice-vegetable pea-greengram; and rice-potato-maize sequences) for two years on an experimental field (clay loam) located at Norman E Borlaug Crop Research Center, Pantnagar, India. The resource conservation technologies (RCT) i.e. reduced tillage, mulch, and 100% RDF had recorded 2.5 and 3.0% higher system productivity and relative production efficiency in rice-vegetablepea-greengram and rice-potato-maize sequences, respectively in two consecutive years. Conservation tillage had sequestered three times higher carbon than conventional tillage while mulching acted four times higher than non-mulched condition in agricultural soils. Even though cropping system not significant significantly influenced on carbon sequestration, rice-vegetablepea-greengram sequence had recorded higher carbon sequestration rate and higher soil organic carbon stock noted in surface plough sole layer than any other cropping systems. Therefore, our results suggested that Indo-Gangetic farmers should consider adopting resource conservation practices together in indogangetic area because of benefits to soil health, carbon sequestration and system productivity.
ABSTRACT
Aim: The study aimed to identify the optimum tillage and source of nitrogen for refining yields, yield sustainability and rainwater-use efficiency, and to develop predictive models explaining the relationship between crop yield and monthly rainfall with main goal of reduced cost of cultivation and increased profitability for long-term sustainability of maize-wheat system. Methodology: A long-term field experiment on maize-wheat system was conducted from 2000 to 2012 at Regional Research Station, Ballowal Saunkhri, Punjab Agricultural University, Ludhiana in split plot design with three replications. The treatment included three tillage practices, viz., conventional tillage (CT), reduced tillage (RT1) and RT1 + herbicide (RT2) in the main plots and three nitrogen (N) management practices, viz., 100% N from organic source (F1), 50% N from organic + 50% N from inorganic source (F2) and 100% N from inorganic source (F3) in the sub-plots. The parameters included maize and wheat yield, rainwater use efficiency, economics, sustainability yield index to develop predictive models. Results: Prediction models expressing relation between yield and monthly rainfall showed beneficial effect of rainfall in June, July and September months on maize and January and February in wheat on crop productivity. RT2 gave highest mean maize grain yield (2264 kg ha−1) with 13.8 and 1.8% yield superiority over RT1 and CT, respectively. However, in wheat, CT recorded highest grain yield (2110 kg ha−1) with 7.9 and 1.7% higher yield than RT1 and RT2, respectively. The RT2F3 gave highest net returns of US$ 222.60 ha−1 with benefit-cost ratio (B:C) of 1.88, rain water use efficiency (RWUE) of 4.78 kg ha−1 mm−1 and a sustainable yield index (SYI) of 60.7% in maize, whereas in wheat it provided net returns of US$315.45 ha−1 with B:C of 2.28, RWUE of 23.0 kg ha−1 mm−1 and SYI of 47.4%. Interpretation: The efficient rainwater use and optimum yields of rainfed maize-wheat system can be realised with reduced tillage + herbicide based weed management along with application of recommended nitrogen. The study suggests the shift from conventional tillage practices to reduced/conservation tillage practices.
ABSTRACT
This study aimed to assess the sweet potato tuberous roots yield under different soil managements and harvesting periods. The experimental design was in randomized blocks in split-plot scheme. The plots corresponded to four soil managements: conventional tillage with Urochloa decumbens straw incorporated and making mounds (PCCP), conventional tillage without straw and with making mounds (PCSP), reduced tillage with straw on the soil surface (PRCP) and reduced tillage without straw (PRSP). The subplots were divided in four harvesting periods: 90, 120, 150 and 180 days after planting. The study showed that sweet potato crop has higher total and commercial tuberous roots yields due to higher numbers of total and commercial roots in soil under conventional tillage with (PCCP) and without straw (PCSP). Thus, the conventional tillage is better to the sweet potato crop.
Este trabalho objetivou avaliar a produtividade de raízes tuberosas de batata-doce em diferentes sistemas de preparo do solo e épocas de colheita. O delineamento experimental foi em blocos ao acaso, em esquema de parcelas subdivididas. As parcelas corresponderam a quatro sistemas de preparo do solo: preparo convencional com palha de Urochloa decumbens incorporada e confecção de leiras (PCCP), preparo convencional sem palha e com confecção de leiras (PCSP), preparo reduzido com manutenção de palha na superfície (PRCP) e preparo reduzido sem palha (PRSP); e as subparcelas, a quatro épocas de colheita: 90, 120, 150 e 180 dias após plantio. Entre os sistemas estudados, a cultura da batata-doce apresenta maiores produtividades total e comercial de raízes tuberosas em função de maiores números total e comercial de raízes tuberosas em solo manejado sob preparo convencional, tanto com (PCCP) como sem palha (PCSP). Assim, o preparo convencional do solo é mais adequado ao cultivo da batata-doce.