Rice stink bug development, feeding preference, sampling techniques and damage effects on rice yield.

摘要

Rice stink bug, Oebalus pugnax (F.) (Hemiptera: Pentatomidae), is a pest of rice in the United States. Development of an effective IPM program requires a better understanding of stink bug biology relative to temperature, alternate host preferences and the development of a more efficient sampling program in rice and/or on alternate grass hosts. An updated economic threshold for stink bug is needed due to differing varietal susceptibility.;Duration of stink bug development (egg to adult) differed significantly at 15°, 21°, 23° or 29°C. A lower development temperature threshold of 14°C was determined by linear regression of temperature (T) versus rate of rice stink bug development (y = 0.004 T - 0.052; r2 = 0.98; P < 0.05). Total degree-day value from egg to adult (thermal constant) was between 249.4 to 281.1 DD.;Feeding response, mating frequency and fecundity potential of rice stink bug on an artificial rice flour diet were comparable to wild host grasses, such as ryegrass and dallisgrass.;Total number of stink bugs in sweep net samples differed significantly over dates (F = 11.88; df = 5, 287; P < 0.0001) and time of day (F = 7.85; df = 2, 287; P 13 bugs/trap before rice heading. After 75% rice heading, trap catch of rice stink bug dropped significantly (F = 9.35; df = 15, 158; P < 0.0001) as did visual counts in alternate host grasses ( F = 160.9; df = 6, 111; P < 0.0001). Following rice harvest, there was a sudden increase in trap catches.;In a sleeve cage field study, rice stink bug damage differed significantly among 3 rice varieties (F = 9.99; df = 2, 466; P < 0.0001) and relative to the 3 grain development periods (F = 7.54; df = 8, 466; P < 0.0001). Kernel damage increased significantly (F = 110.37; df = 3, 466; P < 0.0001) as stink bug densities increased. The EIL values calculated for development periods 1, 2 and 3 were 0.09, 0.1 and 0.2 bugs per panicle, respectively.