Sustainable nutritional practices for bittergourd-amaranthus intercropping system

Abstract

A field experiment was conducted at the Instructional Farm, College of Agriculture, Vellayani during 2001-2002 to identify sustainable nutritional practices for enhancing the yield, quality and income from bittergourd and to assess the economics of intercropping amaranthus in bittergourd. The experiment consisted of seven nutrient sources and two cropping systems and was laid out in factorial RBD with three replications. The various nutrient sources as well as cropping system exerted significant influence on growth parameters and yield attributing characters of bittergourd. Application of 50 per cent N as poultry manure + 50 per cent N as chemical fertilizer significantly increased the growth, yield attributes and the total yield. Bittergourd grown as pure crop showed increase in growth parameters, yield attributes and yield. The nutrient sources influenced the quality characters of bittergourd. Keeping quality was higher for vermicornpost treatment while ascorbic acid content and iron content were higher for the integrated application of poultry manure and chemical fertilizer. Highest value for NPK content of plants and NPK uptake was obtained when chemical sources of nitrogen was substituted with poultry manure in I: 1 ratio. The soil physical properties were improved significantly by the application of organic manures alone. Soil available nitrogen and potassium were higher for the treatment in which 100 per cent N was applied as vermicompost.

The depth of root penetration was not affected by intercropping in bittergourd and amaranthus. The root spread was more in amaranthus when grown as an intercrop compared to sole cropping. The nutrient release pattern of organic manures had shown that there is a progressive increase in the availability of Nand P20S till the 90th day and for available K20 there was a progressive increase upto 60th day and thereafter decreased. Among the three organic manures, poultry manure showed higher availability of the three nutrients. The economics of cultivation revealed that application of 50 per cent N as poultry manure + 50 per cent N as chemical fertilizer gave the maximum net returns and benefit-cost ratio. The net returns and B:C ratio were higher under bittergourd-amaranthus intercropping system compared to sole crop of bittergourd.