|Sebesta Emil E, - 6217-05-10 RETIRED|
|Young Harry C Jr, - OKLA STATE UNIV RETIRED|
|Webster James A,|
Submitted to: Crop Science
Publication Type: Germplasm Release
Publication Acceptance Date: December 23, 1994
Publication Date: N/A
Interpretive Summary: Germplasm registration; no new research reported; no interpretive summary required.
Technical Abstract: OK65C77-6 and OK65C93-8 are winter wheat germplasm lines resistant to wheat streak mosaic virus. These lines were developed by USDA-ARS in cooperation with the Oklahoma Agric. Exp. Stn. and were formally released in 1971. The source of wheat streak mosaic virus resistance originated from a wheat X Agropyron elongatum hybrid line, designated P3-19, developed by W.J. Sando and identified as WSMV-resistant by H.H. McKinney. Subsequent tests in the greenhouse and field showed the line to be highly resistant to WSMV using manual inoculating techniques. In 1963 seed of a 44-chromosome, P3-19 derivative were irradiated with thermal neutrons at the Brookhaven National Laboratory, Upton, NY. Plants obtained from the irradiated seed were used as males in crosses with 'Wichita' wheat in 1964. Screening and selecting in the greenhouse and the field at Stillwater, OK, resulted in the identification of two WSMV-resistant, wheat-like lines with 2n=42 chromosomes. These 2 lines originated from 2 different irradiated seeds. OK65C77-6 and OK65C93-8 are composites of lines selected in the N5 generation. Both lines were stable in their WSMV resistance reaction and chromosome number through the five cycles of screening and selection. OK65C77-6 is classified as tall and early, spikes are awned with white to light amber chaff and amber grain. OK65C93-8 is similar to OK65C77-6 in plant type, with white chaff and red grain. These lines have not been evaluated for other pest resistance or agronomic traits. Written requests for small quantities of seed should be sent to the corresponding author. Recognition of origin of this germplasm should be indicated whenever it is used for research or breeding purposes. Seed will be maintained at the USDA-ARS Plant Science Research Laboratory, Stillwater, OK.