Paddy straw compost application to increase nitrogen fixation on soybean cultivars

Abstract

Soybean is leguminous crop requiring large quantity of N nutrient. The N requirement in soybean crops can be fulfilled through N 2 fixation by root nodules. Root nodules can develop through the symbiosis of soybean crops with Rhizobium bacteria. This study aimed to identify the effects of paddy straw compost application on nitrogen fixation and physiological character in Baluran, Tanggamus, Seulawah, Grobogan cultivars of soybean crops.The study was conducted at regosol soil in Banguntapan, Yogyakarta.Result has showed that paddy straw compost dosage may increase soybean capabilityto perform nitrogen fixation,indicated by the variables of total root nodules, root nodule dry weight, andnitrogenase activity. Paddy straw applicationhas not provided significant effect on total chlorophyl content, leaf greeness, water content in leaf, transpiration rate and CO 2 content in leaf, but has given significant effect on net assimilation rate of the crops.