Document Type

Thesis - University Access Only

Award Date


Degree Name

Master of Science (MS)

Department / School

Plant Science


Ten lines of winter wheat (Triticum aestivum L. em. Thell) were evaluated over two years for their reaction to dilutions of wheat streak mosaic virus (WSMV), a member of the family Potyviridae in the genus Tritimovirus. Plants were mechanically inoculated with inoculum dilutions of 1 :5, 1 :10, and 1 :20 (ratio of infected tissue to extraction buffer). Various traits were evaluated for dosage effect including visual disease rating, ELISA, fresh leaf weight, plant height, yield, test weight, protein content, primary spike head length, number of spikelets per head, number of seeds per ten heads, and hundred-kernel weight. ELISA readings confirmed infection in all ten lines (P= 0.0001 ). Dilution (inoculum dosage) was found to significantly affect plant height (P=0.0018), kernel protein analysis (P=0.0200), spike length (P=0.0265), kernel number (P=0.0152), kernel weight (P=0.0130), and hundred-seed weight (P=0.0346). These results prove that the expression of viral disease resistance in winter wheat varieties is affected by dilution (dosage level of inoculum).

Library of Congress Subject Headings

Winter wheat -- Disease and pest resistance
Wheat streak mosaic virus



Number of Pages



South Dakota State University