The rice stink bug, Oebalus pugnax (F.), is an important late season pest of rice that is noted for causing grain yield and quality reductions in the United States. This study investigated rice injury using field cages in two rice cultivars (‘Cocodrie’ and ‘Wells’) at bloom, milk, and soft dough stages and O. pugnax ecology in the Delta Region of Mississippi. Specific objectives were: 1) to determine the impact of adult O. pugnax infestation on rice yield and grain quality at bloom, milk, and soft dough stages of rice development; 2) to determine the impact of adult O. pugnax gender and infestation duration on rice yield and grain quality at the milk stage of panicle development; 3) to identify and examine the seasonal abundance and phenology of O. pugnax on non-cultivated host grasses; and 4) to evaluate feeding preference and development of O. pugnax on host grasses. Rice injury increased as O. pugnax density increased. The bloom and milk stages were the most vulnerable to blank and discolored kernels, respectively. O. pugnax feeding injury was significant after 3 d of infestation duration during the milk stage of panicle development. Female O. pugnax caused a greater percentage of blank kernels compared to males. A survey of O. pugnax hosts indicated that Italian ryegrass, Lolium perenne L. ssp. multiflorum and winter wheat, Triticum aestivum L., were important hosts during spring and early summer. Junglerice, Echinochloa colona (L.) Link; crabgrass spp., Digitaria spp. Haller; southwestern cupgrass, Eriochloa acuminata (J. Presl) Kunth; and praire cupgrass, Eriochloa contracta (Hitchc.), were important hosts for O. pugnax during early to mid-summer. Browntop millet, Urochloa ramosa, and broadleaf signalgrass, Urochloa platyphylla, supported adult O. pugnax prior to overwintering. In a choice test of wild host grasses, junglerice was the most preferred over 10 other host grasses. In the no-choice test, mean development time was shorter and survival was greater for O. pugnax nymphs reared on rice, Oryza sativa L., compared to dallisgrass, Paspalum dilatatum Poir and junglerice. These results provide biological and ecological information on which new O. pugnax integrated pest management practices can be developed.

Field and greenhouse experiments were conducted from 2003 to 2006 at the Texas A&M University Agricultural Research and Extension Center at Beaumont and commercial rice fields throughout the Texas Rice Belt with the objectives of characterizing the nature of rice stink bug, Oebalus pugnax (Fabricius), damage to rice, Oryza sativa L., and developing visual sampling methods and sequential sampling plans. During 2005 and 2006, in greenhouse and field experiments, rice plants were caged and infested with adult or nymph O. pugnax during the heading, milk or soft dough stage. No differences were found in the weight of rough, brown or milled rice infested with O. pugnax during different stages. More peck was found in grain from plants infested during milk and soft dough than heading. Adult O. pugnax caused more peck than nymphs in all stages. In field experiments conducted during 2005 and 2006, single rice panicles were caged at the onset of heading and infested with one male or female O. pugnax for 48 h during the heading, milk, soft or hard dough stage. No differences were found in the weight of rough rice per panicle infested with O. pugnax. No differences were detected in percentage peck caused by male and female O. pugnax. Infestation during all stages of panicle development produced significantly more peck than no infestation In greenhouse experiments conducted during 2004 and 2005, rice plants at the pre-heading, heading, milk and soft dough stages were caged together and infested with male and female O. pugnax. Insects were observed for a period of five days and their preferences recorded. More insects were observed on milk and soft dough than on pre-heading or heading plants.Commercial rice fields throughout the Texas Rice Belt were sampled during 2003 and 2004 and visual sampling methods were compared to the sweep net method of sampling. Analysis of covariance showed that one sweep of the “long stick” or two sweeps of the “sweep stick” compared favorably to 10 sweep net sweeps. Analyses revealed that visual sampling using the long stick is more cost-reliable than sweep net sampling for O. pugnax in Texas rice fields.

Field and greenhouse experiments were conducted from 2003 to 2006 at the Texas A&M University Agricultural Research and Extension Center at Beaumont and commercial rice fields throughout the Texas Rice Belt with the objectives of characterizing the nature of rice stink bug, Oebalus pugnax (Fabricius), damage to rice, Oryza sativa L., and developing visual sampling methods and sequential sampling plans. During 2005 and 2006, in greenhouse and field experiments, rice plants were caged and infested with adult or nymph O. pugnax during the heading, milk or soft dough stage. No differences were found in the weight of rough, brown or milled rice infested with O. pugnax during different stages. More peck was found in grain from plants infested during milk and soft dough than heading. Adult O. pugnax caused more peck than nymphs in all stages. In field experiments conducted during 2005 and 2006, single rice panicles were caged at the onset of heading and infested with one male or female O. pugnax for 48 h during the heading, milk, soft or hard dough stage. No differences were found in the weight of rough rice per panicle infested with O. pugnax. No differences were detected in percentage peck caused by male and female O. pugnax. Infestation during all stages of panicle development produced significantly more peck than no infestation In greenhouse experiments conducted during 2004 and 2005, rice plants at the pre-heading, heading, milk and soft dough stages were caged together and infested with male and female O. pugnax. Insects were observed for a period of five days and their preferences recorded. More insects were observed on milk and soft dough than on pre-heading or heading plants.Commercial rice fields throughout the Texas Rice Belt were sampled during 2003 and 2004 and visual sampling methods were compared to the sweep net method of sampling. Analysis of covariance showed that one sweep of the “long stick” or two sweeps of the “sweep stick” compared favorably to 10 sweep net sweeps. Analyses revealed that visual sampling using the long stick is more cost-reliable than sweep net sampling for O. pugnax in Texas rice fields.