Assessing maize based cropping systems for higher productivity and income under shifting cultivation in eastern Indian Himalayas

Abstract

Low productivity, income and degradation of soil fertility are the key characteristics of primitive practice of jhum farming (shifting cultivation) due to no fertilizer / manure application and lack of conservation measures. Thus, the objective of the study was to identify suitable maize based intercropping and sequential cropping systems for higher productivity and income along with conservation of natural resources (moisture, nutrient, soil, etc.). The study was conducted with five maize (Zea mays L.) based systems with and without retention of maize stalk mulch (MSM) for succeeding French bean crop in the rabi season in a fresh jhum land through farmers' participatory mode consecutively for two year (2014 and 2015) at Sonidan village, Ri-bhoi district of Meghalaya, India. The five maize based systems [sole maize, maize - French bean (Phaseolus vulgaris L., pole type), Maize - French bean (bush type), Maize + groundnut (Arachis hypogea L.) - French bean (pole type) and Maize + groundnut - French bean (bush type)] and two conservation practices for succeeding French bean [in-situ MSM and no mulch] were tested in a factorial randomized block design with three replications. The yield attributes of maize (number of row cob-1, number of seeds cob-1 and test weight) as well as grain and straw yields were not significantly affected by conservation practices (mulching, intercropping of legume). Intercropping of groundnut in maize (paired row planting in additive series) gave 300-345 kg groundnut (kernel yield) ha-1 without any yield penalty on maize. All the maize-legume systems significantly enhanced maize equivalent yield (MEY) over sole maize. Gross return, net return and B:C ratio were recorded highest in maize + groundnut - French bean (bush type) cropping system and in-situ MSM. Retention of MSM significantly enhanced MEY in both the years of the study relative to residue removal. The conservation practice of MSM retention had positive effect on the soil organic carbon (SOC) only in second year. Though there was a trend of improvement in soil fertility (available N, P, K) due to inclusion of legumes in cropping system and MSM conservation measure, it remained statistically insignificant. Maize + groundnut - French bean (bush type) system along with in-situ MSM is a sustainable practice in jhum farming for increasing productivity and sustaining SOC which may help in extending the duration of land available for cultivation under jhum system.