H. D. Catling, J. Louwen, R. Pattrasudhi. 1994. Ecological studies on yellow stemborer in deepwater rice in Thailand. Thai Journal of Science 27: 325-339.

Abstract: Yellow stem borer, Scirpophaga incertulas (Walker), the major insect pest attacking deepwater rice in Asia, was studied under farmers' field conditions in the equatorial climate of Thailand's Central Plain from 1981 to 1984. The stem borers Chilo polychrysus (Meyr.) and Sesamia inferens (Walker) were of lesser importance. During the preflood period of deepwater rice, S. incertulas populations of 2-3 immatures/m2 damaged 1-2 percent of the stems, though in 1982 an early build-up of 4-8 immatures/square m caused 6-9 percent damage. In the main flood-period the population density usually increased slightly to cause stem damage of 4-10 percent. As the floodwater subsided the density rose to 10-15 immatures/square m taking the

stem damage of the maturing crop to 31-42 percent. The incidence of dead hearts and whiteheads was low and always below the proportion of damaged stems. Larval activity at the beginning of the dry season further increased stem damage to 45-47 percent but borer populations declined to 1 immature/m2 in February.

Keywords: rice Oryza sativa, rice yellow stem borer, damage, bionomics, population dynamics, other pests: rats, rice gall midge Orseolia oryzae, rice stem borers, stem damage, population fluctuation of S. incertulas, egg parasitism, Telenemous rowani, Tetrastichus schoenobii, insect egg parasitoid, spider predators, Araneus inustus, tetragnathids, Tetragnatha javanica. T. virescens, Clubion japonicola, Lycosa, Conocephalus longipennis, Euscyrtus concinnus, Agriocnemis sp., Ceriagrion olivaceum, Ophiona indica, Paederus fuscipes, Miraspis discolor, Orius tantillus