Kadar Air Kapasitas Lapang dan Bobot Jenis Tanah yang Optimal untuk Pertumbuhan dan Produksi Umbi Uwi (Dioscorea alata L)

Abstract

Food diversification is one of the ways in order to achieve national food security. One of the alternative food that has the potential to be developed is tuber of Dioscorea alata (uwi, ubi kelapa, keribang, water yam). The aim of this experiment was to determine optimum water content of field capacity and spesific weight of the tuber growing space of Dioscorea alata to produce maximum growth and tuber productivity. The experiment was arranged in Randomized Complete Block Design with five replications. The treatment of this research included without planting hole, with planting hole, husk addition as much as 50% of planting hole volume, husk and manure addition as much as 50% and 25% of panting hole volume, manure addition as much as 25% of planting hole volume. The result of this experiment shows that the treatment give significant effect on the physical characteristics of the soil and vegetative growth of plants (except plant height variable), but no significant effect in increasing the productivity of tubers. For the physical characteristics of the soil, the addition of planting hole, husks and manure has the lowest value of soil density and the highest value of soil field capacity. For the vegetative growth phase, planting in planting hole and addition of husks and manure has the highest number of leaves and the number of branches.The optimum water content of field capacity and spesific weight of the tuber growing space was 39.68 % dry weight based and 0,69 g.cm-3 respectively.