Effect of Relay-Planting Several Legume Species at Various Ages of Rice on Growth and Yield of Red Rice Grown Together with Legume Crops under Aerobic Irrigation System

This study aimed to examine the effects of relay-planting several species of legume crops at various ages of rice plants on growth and yield of red rice grown together with legume crops in pot culture under aerobic irrigation systems. The pot experiment was carried out in a plastic house from August to December 2018, designed according to the Complete Randomized Design with three replications and two factorial treatment factors, namely legume species (s1= peanut var. Hypoma-3, s2= mungbean var. Kenari, s3= soybean var. Dering-1), and ages of red rice when the legume crops were relay-planted (u1= relay-planting at 1 week after seeding rice (WASR), u2= 2 WASR, u3= 3 WASR, and u4= 4 WASR). The results indicated that the ages of rice when the legume crops were relay-planted showed more significant effects on growth and yield components of the red rice compared with the legume species did, but there were no interaction effects between the two treatment factors tested. Among the various ages examined, relay-planting legume crops when the red rice age was 3 weeks resulted in the highest growth and yield components of the red rice examined, in which the mean values of tiller number (26.2 tillers/clump), panicle number (20.4 panicles/clump), filled grain number (1030 grains/clump), and grain yield (26.88 g/clump) were highest compared with relay-planting legume crops at other times. Among the species of legume crops examined, mungbean var. Kenari grown together with the red rice resulted in the highest average of red rice grain yield (25.99 g/clump) as well as the highest harvest index (47.01%) compared with the other legume species.