Pengaruh Tiga Jenis Mangsa terhadap Biologi Kepik Predator Sycanus annulicornis Dohrn. (Hemiptera: Reduviidae)

Abstract

The objective of the research was to study the effects of (1) three different spesies of preys on the biology of predator S. annulicornis, (2) ratio of female to male on the fecundity and fertility of the predator, and (3) prey status on the predator behaviors. The research was held at Ecology Laboratory, Departemen Proteksi Tanaman, Fakultas Pertanian, IPB, since July 2005 until June, 2006. Predator S. annulicornis was collected from agricultural field of Kebun Percobaan IPB Sawah Baru and Situ Gede, Darmaga Bogor. Preys used were Corcyra cephalonica Stainton (Lepidoptera: Pyralidae), Tenebrio molitor Linnaeus (Coleoptera: Tenebrionidae), and Spodoptera litura Fabricius (Lepidoptera: Noctuidae), both as dead and alive larvae. Larvae and adult of C. cephalonica was collected from rice warehouse at Cianjur and surroundings, larvae T. molitor from local market at Bogor, while larvae S. litura from soybean fields at Kampus IPB Darmaga. Those preys then were reared in the laboratory. The study revealed that C. cephalonica was the most suitable prey for S. annulicornis. It resulted in the lower mortality rate (17,5%), shorter nymphal period (51,42 days), longer longevity (30,25 days), higher adult weight (0,12 g) and higher ECI value (33,46%). On the other hand, S. litura was unsuitable prey for S. annulicornis. It resulted in higher mortality rate (70%), longer nymphal period (58,31 days), shorter longevity (18,50 days), lower adult weight (0,07 g), and lower ECI value (8,32%). The sex ratio of 1:2 was the most suitable for mass rearing of the predator in laboratory, because it generated highest fecundity (74,14 eggs) and highest fertility (65,14 eggs). Prey given as dead larvae did not affect the predatory behavior of the offsprings.