Morphological and meristical study on rice bugs Leptocorisa Oratorius (Fabricius, 1764) at the paddy fields in Kuala Pilah and Bahau / Norjasmin Hussin

The major pest found at paddy field is rice bugs, from genus Leptocorisae, Leptocorisa oratorius as they feeds on the panicle of the rice. Leptocorisae bug usually found in the paddy field and lowland grass areas according to their adaptations. There were 308 individuals of Leptocorisa oratorius (Hemiptera: Alydidae) collected from two different areas in selected paddy field of Kuala Pilah; Kampung Kuala Serdang and Kampung Lonek. High abundance of L. oratorius was found in miking stage of paddy compared to soft dough stage can help warn the farmers and create awareness towards the well-being paddy. A total of seven morphometric characteristics measurements were measured and four meristic characteristics were observed using dissecting microscope. The L. oratorius can easily identified based their spots on the abdomen at ventral-lateral, and spot behind the compound eye where this feature was not seen in any other Leptocorisae. All the characters were found significantly difference (P<0.05) except for the antenna and hindlegs. Besides, the standard error of morphometric characteristics show the lower value as there is slightly difference in body length and the wings between two sampling sites. Higher number of L. oratorius presence at milking stage paddy field will jeopardize the paddy yield if they are in high abundance. Therefore, this research can be more interesting if the location is more than two paddy fields and using PCR methods. This is because PCR is more accurate and can determine the DNA of L. oratorius