CONSERVATION AGRICULTURE EFFECTS ON SELECTED SOIL QUALITY PARAMETERS UNDER CEREAL-CEREAL-LEGUME AND CEREAL-LEGUME-LEGUME CROPPING SYSTEM IN FAR WESTERN NEPAL
Nepal Agricultural Research Council, Nepal
Keywords:conservation agriculture, cropping system, bulk density and soil organic carbon
Conservation agriculture (CA) practices improve soil quality and recuperate degraded soils. This experiment was carried out at the research field of Regional Agricultural Research Station, Bhagetada, Dipayal, Doti, Nepal for two consecutive years 2014/15 to 2015/16 to determine the effect of maize based conservation agriculture system on soil quality parameters namely bulk density and soil organic carbon. This study examined the effects of the two cultural practices (conservation agriculture and conventional agriculture), two cropping systems (cereal-cereal-legume and cereal-legume-legume) and two varieties of maize [(Zea mays L.) (Rajkumar and Arun2)], two varieties of wheat [(Triticum aestivum L.) (Dhaulagiri and WK 1204)], two varieties of lentil [(Lens culinaris Medik.) (Shimal and Khajura1)] and two varieties of mungbean [(Vigna radiata L. Wilczek) (Pratikshya and Kalyan)] in the varietal sequence of Rajkumar-Dhaulagiri and Shimal-Pratikshya, Rajkumar-WK 1204 and Khajura1-Pratikshya, Arun2-Dhaulagiri and Shimal-Kalyan and Arun2-WK 1204 and Khajura1-Kalyan. The treatments were laid out in split-split plot design with four replications. Results indicated that the bulk density of maize-wheat-mungbean cropping system was lower (1.65 g/cm-3) than that of maize-lentil-mungbean cropping system (1.66 g/cm-3). The bulk density of CA practices was found higher (1.67 g/cm-3) than that of conventional agricultural practices (1.65 g/cm-3). The ratio of soil organic carbon (SOC) increment under cereal-legume-legume cropping system and conservation agricultural practices was 1.5% (1.38) and 11.6% (1.44) higher than cereal-cereal-legume cropping system (1.38) and conventional agricultural practices (1.29), respectively. Similarly, the ratio of SOC increment obtained from the interaction effect of cereal-legume-legume cropping system, CA practices and varietal sequences of hybrid maize, followed by lentil and mungbean was 8.6% higher (1.51) than that of cereal-cereal-cropping system, conservation agricultural practices and varietal sequences of hybrid maize, followed wheat and mungbean (1.39). So, the farmers of far western river basin agro-environment are suggested to adopt maize-lentil-mungbean cropping system, conservation agricultural practices and varietal sequence of hybrid maize, followed by lentil and mungbean variety to improve soil quality.