PRESENCE AND OVIPOSITION PREFERENCES OF Rhyzopertha dominica (Fabricius) (Coleoptera: Bostrichidae) ON SEVERAL NEW SUPERIOR VARIETIES OF RICE

Abstract

New Superior Varieties (VUB) of rice is result from agricultural innovation to increase rice productivity in Indonesia. VUB of rice can increase productivity (8.51 t/ha), income (65.7%), and rice production (1.5–33.71%). With this increase in rice production, storage properties are needed to maintain the availability and quality of rice. However, the main obstacle in rice storage is the infestation of stored product pest Rhyzopertha dominica (Fabricius) (Coleoptera: Bostrichidae). R. dominica can infest unhulled rice and milled rice in storage. Therefore, this study was conducted to examine the presence and oviposition preferences of R. dominica on several unhulled rice and milled rice of new superior varieties (i.e., Baroma, Inpara 9 Agritan, Inpari Gemah, Inpari 43 Agritan GSR, Ciherang, and Inpari 42 Agritan GSR) using the antixenosis resistance mechanism. The results showed that the presence and oviposition preferences of R. dominica were influenced by physical factors of the diet (form and grain hardness). The presence and oviposition of R. dominica were higher and there was a clustered distribution (clumped) on the milled rice compared to the unhulled rice. Some milled rice has a lower grain hardness level than unhulled rice, so it is more attractive to R. dominica to be present and lay eggs. However, chemical factors of the diet, such as phenol content, water content, carbohydrate, protein, fat, and ash contained in several unhulled rice and milled rice, did not significantly affect the presence and oviposition preferences of
R. dominica.