Susceptibility of Milled Rice Varieties to the Lesser Grain Borer (Rhyzopertha dominica, F)

Abstract

The susceptibility of six milled rice varieties (IR-64, Ciherang, Membramo, Cibogo, Sembada, and Intani-2) to the Lesser Grain Borer (Rhyzopertha dominica, F) was studied by No Choice Test Method under laboratory condition (27 ± 2°Cand 65 ± 5% RH). The Susceptibility was assessed on the basis of eggs number laid by female insects, the number of F1 progeny emerged, the weight loss of infested samples and also the Dobie’s Index of susceptibility. The results revealed that the number of eggs laid by female insects, the number of F 1 progeny emerged and weight loss of infested samples were significantly low in Membramo variety followed by Ciherang, IR-64, Cibogo, Sembada and Intani-2. Based on the index of susceptibility, the milled rice variety of Membramo had the lowest susceptibility index and was regarded as resistant. While the milled rice varieties of Ciherang, IR-64, Cibogo and Sembada were considered as moderately resistant, Intani-2 seen as the most highly susceptible. These results imply that the milled rice variety with high phenolic content and hardness potentialy revealed resistant to the R. dominica infestation.