Cogon grass (Imperata cylindrica L.) mulch effect on microclimate, weed management and yield of upland rice

One of the problems of upland rice cultivation in dry land is the availability of water needed to maintain humidity and temperature around plant roots. Cogon grass (Imperata cylindrica L.) mulch which has a long decomposed duration, can be an alternative to maintain the microclimate humidity and control weeds. This study aimed to obtain the best dose of cogon grass mulch on microclimate, weed management and upland rice yield on ameliorated ultisol soils. The research was carried out using a randomized complete block design with five doses of cogon grass mulch, i.e. 0, 10, 15, 20, and 25 tons/ha and three replications. Data were analyzed statistically by the F test at a 5% significance level and mean comparison using Tukey’s test. Results showed that applying cogon grass mulch could reduce temperature and increase the soil’s moisture. Biomass and species of weeds decreased with increasing doses of cogon grass mulch. Applied 10 tons/ha of cogon grass mulch effectively suppresses weed growth by 42.8%. Cogon grass mulch application did not affect upland rice growth variables, but 20 t/ha mulch significantly increased the yield by 21.7%.