Resistance Level of Soybean Genotypes against Pod Sucking Bug (Riptortus linearis F. Hemiptera: Alydidae)

Abstract

Background: Pod sucking bug (Riptortus linearis F. Hemiptera: Alydidae) is one of the major insect pest in soybean that cause yield loss up to 79%. This study was carried out to identify the level of resistance to pod sucking bug on soybean genotypes. Methods: Field research was conducted at Muneng Experimental Farm, Probolinggo, East Java, Indonesia in the Dry Season (March-June) 2019. A randomized block design repeated two times were used on a total of 16 soybean genotypes included two varieties (Anjasmoro and Gema) as check. The experiment consisted of two growing environments namely controlled environment (P1): two insecticides with active ingredients Deltamethrin and Fipronil were applied to soybean crops alternately; and uncontrolled environment (P0): no insecticide was applied to soybean crops Observations were recorded on the intensity of borer attack and dry seed weight. Result: In uncontrolled environment (P0), the percentage number of infected seed to healthy seed was higher than that in controlled environment (P1). The mean effectiveness of control of pod sucking was 35% which was based on infestation intensity of seed number/plant infected in in two environments. The total seed weight/plant in controlled environment (P1) was 95% higher than that in uncontrolled environment (P0). Based on infestation intensity in uncontrolled environment (P0), five genotypes (G1 to G5) were categorized as resistant against pod sucking bug while the check varieties Anjasmoro and Gema were categorized as moderate resistant and susceptible, respectively.