Additive intercropping with peanut increases growth and yield of various promising lines of red rice under aerobic irrigation system on permanent raised-beds

Cereal-legume intercropping can potentially increase yield of the intercropped cereals such as maize and rice. The aim of this research was to examine whether relay-planting peanut between rows of several promising lines of red rice could increase growth and yield of irrigated aerobic red rice. The Split Plot design was used to arrange the experiment consisting of three blocks and two treatment factors. The main plot factor was red rice line comprising four genotypes (G04, G10, G15 and G21) while the subplot factor was intercropping comprising two treatments (T0= monocropped rice, T1= rice-peanut intercropping). The results indicated that the rice-peanut intercropping could significantly increase red rice growth and yield while different lines only affected plant height and some yield variables. However, plant height and grain yield showed significant interactions of the treatment factors, in which G21 intercropped with peanut had the highest yield (47.16 g/clump equivalent to 9.34 tons/ha), while the lowest yield was on monocropped G04 (21.55 g/clump equivalent to 4.31 tons/ha). These indicated different responses among the red rice lines to additive intercropping with peanut, in which G21 showed the highest yield increase, followed by G15 and G04, while G10 showed no significant yield increase due to intercropping.