Browse on keywords: insect ID wheat
Search results on 02/20/18
2664. Holbert, S., L.E. Sandvol, B. Stoltz, and R. Johnston. 1988. Russian wheat aphid.. ID Agr. Expt. Sta. CIS #817.
First found in Idaho in early 1987; spread throughout state that season; infests wheat, barley, triticale, other grasses; volunteer grain an important host; aphid secretes a toxin that causes leaf rolling and plant streaking (purple in cool weather, white in hot weather); control threshold when > 10% of tillers are infested in spring; insecticide control listed.
3180. Simmonds, B. and D. Brosten. 1991 Oct.. Biocontrol blitz targets Russian wheat aphid.. Agrichemical Age 34(9):8-10, 35.
The article describes current efforts to develop biocontrols for the Russian wheat aphid. Parasites and predators are being released and tested in a number of areas, including WA and ID. Wheat varieties are being screened for resistance to the pest. No one expects biocontrols to eliminate the need for occassional insecticide treatments, but hope they will reduce the frequency of chemical control by keeping the aphids below the economic threshold. A national IPM program has been established for RWA control.
5235. Pike, K. and D. Allison. 1990. Control of small grain aphids on winter wheat.. unpublished research results, WSU IAREC, Rt. 2, Box 2953-A,.
Describes 1989 research results of screening 12-15 insecticides on both hard red and soft white winter wheat at the Irrigated Research Center in Prosser. All insecticides reduced aphid numbers compared with the check. Three aphids were monitored - Russian wheat aphid, bird cherry-oat aphid, and English grain aphid.
6499. Smith, Larry. May 1990. Hessian fly.. Farm Scene, UI Nez Perce Co. Extension newsletter.
Infestations of Hessian fly in the PNW have largely been restricted to the irrigated areas. Wheat is the preferred host for the insect. There are usually 2 spring generations, thus making spring wheat more susceptible to damage. Oats are not infested, and barley and rye suffer little damage. The fly feeds on the juices of the stem tissue at the crown of young plants or above the nodes on jointed plants. Tiller development can be reduced by feeding. Economic grain losses can occur if more than 20% of tiller are infested. Crop loss has been found to increase where wheat, mostly spring wheat, is seeded into wheat stubble or reduced tillage. Tillage operations which bury residue prevent emergence of the fly. Resistant varieties of spring wheat are available, and Wakanz, WPB906R and WPB926 have shown yield increases of up to 65% over susceptible lines. Tables on field results of variety screening are included.
6766. Tanigoshi, L.. 1990. untitled. unpublished list, Dept. of Entomology, Washington State Univ., Pullman, WA.
The table lists the natural enemies of the Russian wheat aphid (RWA) Diuraphis noxia, the country of origin, and the release date in WA state. Over ten natural enemies have been released to date.
8343. Wysocki, Don. 1990. Developing resistance to Russian wheat aphid.. STEEP Extension Conservation Farming Update, Spring 1990, p. 7-8.
Work is underway at Pendleton, OR to find resistant wheat varieties for the Russian wheat aphid. South African researchers have found resistance to be conferred by single, dominant genes in some lines. Of 995 lines evaluated at Pendleton, only 20 had some tolerance to the pest.
10416. Smith, L. (ed.). 1991. North central Idaho county extension field crop demonstrations, 1989-1990.. ID Agr. Expt. Sta. Misc. Series 152, Moscow..
The results of numerous on-farm tests are reported. Some tests were replicated, while others were simply demonstrations. The tests were organized by county extension agents.
10682. Simmonds, B. and D. Brosten. 1990. Biocontrol blitz targets Russian wheat aphid.. Agrichemical Age, Oct. 1990, p. 8-10..
Washington State University entomologists have been releasing parasitic wasps since 1988 to help control Russian wheat aphid. USDA_APHIS has released six wasp species, one fly species, and six lady beetle species. The national biocontrol effort against the aphid is part of a broader $2.1 million National RWA IPM program. RWA has infested fields in sixteen western states, and has probably spread near its maximum range. One helpful cultural practice is to eliminate any green host plants in late summer or winter to starve the aphids. Also, planting spring wheat or barley as early as possible can reduce infestations.
10950. Harwood, R.F.. 1989. Countermeasures against Russian wheat aphid in Washington.. EM4835, Cooperative Extension, Washington State Univ., Pullman..
Seven major thrusts for IPM control of RWA are briefly described as part of a national effort. Researchers in Washington are concentrating on aphid population dynamics, natural enemies, insecticides, aphid-resistant cereals, and information dissemination.
10960. Anon.. 1989. Russian wheat aphid control for the Pacific Northwest, spring 1989.. unpublished, Dept. of Entomology, WSU, Pullman, WA.
Scouting procedures for RWA are described. A spray decision table is included to determine if an infestation has reached the economic injury threshold.