Mycorrhiza biofertilizer and intercropping with soybean increase anthocyanin contents and yield of upland red rice under aerobic irrigation systems

Abstract

Red rice kernels are known to have high antioxidant properties due to its anthocyanins, and application of mycorrhizal fungi was reported to increase grain anthocyanins. This study aimed to examine the effects of intercropping with soybean and mycorrhiza biofertilizer on grain anthocyanins and yield of upland red rice under aerobic irrigation system. The experiment was conducted in Beleke, West Lombok, Indonesia, under Split Split-Plot design with three treatment factors, i.e. upland red rice genotypes as the main plots (G04, G10), intercropping as the sub-plots (monocrop or intercropping with soybean), and mycorrhiza as the sub-sub-plots (without or with mycorrhiza). Results indicated that intercropping and mycorrhiza application significantly increased grain anthocyanin contents and yield, but rice genotypes showed differences only in grain yield per clump. However, there was a three-way interaction on percentage of filled grain number, and a two-way interaction on grain anthocyanins, in which mycorrhiza application resulted in more significant increases in anthocyanin contents and grain yield of the red rice under intercropping with soybean than under monocrop. Therefore, application of mycorrhiza biofertilizer and intercropping with soybean, besides increasing grain yield, are also capable of increasing health values of the red rice grown on raised-beds in aerobic irrigation system.