Survey of Rice Pests, Diseases and Natural Enemies on “Upsus” Program in Karawang District, West Java Province

Abstract

"Upsus" (Special Efforts) Program is a program to increase crop production and productivity to support the acceleration of food self-sufficiency held by the government. The targets are to increase the planting index (IP) by 0.5 and productivity by 0.3 ton/ha/Harvested Dry Grain (HDG). Increased productivity has not been reached optimally. This research aimed to determine the number/types of the dominant pests and natural enemies, and pests and diseases attack rates in the wetland rice plantation "Upsus" Program in Karawang District. Direct observation was carried out on four stages of plant development, in the nursery stage (10–14 days after sowing) 200–300 m², seedlings stage (10–20 days after planting), vegetative stage (5–6 weeks after planting), and reproductive stage (1–2 weeks after flowering) respectively within an area of 2000 m². Twenty samples were observed in the nursery stage and 50 samples in the following stages. The dominant pests and diseases found were Nilaparvata lugens, Leptocarisa oratorius, Schirpophaga incertulas, Cnaphalocrocis medinalis, Scotinophara coarctata, Mythimna separata, bacterial leaf blight (Xanthomonas. oryzae pv. oryzae), blast (Pyricularia grisea) and narrow brown spot (Cercospora oryzae). The recorded dominant natural enemies were Cyrtorhinus sp., Paederus sp., Tetragnatha sp., and Pardosa pseudoannulata. S. incertulas showed the highest attack intensity and the highest disease severity was found in bacterial leaf blight. The largest population of dominant pests and natural enemies was found in the generative stage. The high application of pesticides affected the population of pests, natural enemies, and the level of pest and disease attacks.

Energy Allocation of the Wolf Spider Pardosa pseudoannulata under Dietary Restriction

“…Foraging theory predicts that to compensate for the residual effects of dietary restriction, adult spiders that have experienced a shortage of prey in their juvenile stage must show a greater increase in foraging activities after maturity than those spiders that have not experienced dietary restriction during the juvenile stage. In contrast to expectations, female spiders in the restricted group did not increase their foraging activities [30,54]. Dietary restriction may not be harmful; appropriate dietary restriction may enhance performance such as enhancing tolerance to cold and learning ability [55,56].…”

“…Since the mid-1950s, various studies about rice field spiders have been carried out, and the role of rice field spiders as an important predatory natural enemy of farmland pests has been recognised by plant protection experts and entomologists [29][30][31]. Pardosa pseudoannulata is a kind of wolf spider that is beneficial to rice fields because it is the natural enemy of rice pests [32,33].…”