Effect of the Number of Rows and Cultivars of Soybeans on Damage Intensity of Pest and Predator Populations in Corn-Soybean Intercropping, South Sulawesi Indonesia

Abstract

Background: Soybean productivity in Indonesia remains low yield due to the occurrence of pests and diseases. Here, our study aimed to determine the number of soybean rows and varieties in the soybean-corn intercropping system and the damage level, pest and predator populations. Methods: The study used a split-plot design with three replications. The main plot was soybean varieties (Dena-1, Detap-1 and Deja-1) and the subplots consisted of monoculture (soybean); three rows of soybeans and two rows of corn; four rows of soybean and two rows of corn; six rows of soybean and two rows of corn. Result: The six rows of soybeans and two rows of corn showed the lowest attack rate of Spodoptera litura and Etiella zinckenella, the lowest population of Aphis glycines and Riptortus linearis, the highest predatory population of Crocothemis servilia and Coccinella sp. and the highest predator populations of Euborellia annulata. The highest attack rate of S.litura was in Dena-1. In contrast, the highest intensity of E.zinckenella pest damage was in Dena-1 and Deja-1. The corn-soybean intercropping was recommended as the best practice for sustainable agriculture production due to facilitating in the increase of growth of predator population and reducing the level of crop damage due to pest attacks.