Effect of different mulches on soil moisture conservation and productivity of rainfed ginger in an agroforestry system of Mizoram.

摘要

A field study was conducted during 2003-2005 to compare the relative efficacy of three mulches (viz. rice straw, subabul leaf and weeds) and quantities (6, 8 and 10 tonnes/ha) on soil moisture retention and productivity of rainfed ginger in a gamari based agroforestry system in Mizoram. Soil moisture conservation was significantly (P=0.05) affected by mulch type and quantity of mulch applied. Soil moisture retention in the plots was in the order of rice straw > subabul leaf > weeds and 10 t/ha >8 t/ha >6 t/ha mulch applied. The number of sprout, sprout frequency, tiller height and finger size of ginger were better in the mulched plots when compared with the unmulched (control) plots. Ginger yield in the mulched plots was in the order of subabul leaf > rice straw > weeds. The slower decomposition of rice straw caused greater moisture retention while quick decomposition of subabul leaf caused increased addition of nitrogen to the soil thereby increased ginger yield. Our study depicts the favourable role played by the mulches in soil conservation in the hilly terrain of Mizoram. Further, the study demonstrates that the common weeds can be effectively used in conserving soil moisture and improving crop productivity.