Submitted to: Biological and Cultural Tests for Control of Plant Diseases
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 1, 2002
Publication Date: April 1, 2003
Citation: CHEN,W. ., GRUNWALD,N.J., MCPHEE,K.E., MUEHLBAUER,F.J. FIELD EVALUATION OF LENTIL CULTIVARS FOR RESISTANCE TO SCLEROTINIA SCLEROTIORUM. BIOLOGICAL AND CULTURAL TESTS FOR CONTROL OF PLANT DISEASES. Vol. 18. F010. DOI:10.1094/BC18. 2003. Interpretive Summary: White mold is an important disease of lentils under humid conditions. No appropriate control measure is currently available for this disease. Information about relative susceptibility of lentil cultivars to white mold is not available. This experiment was carried out to evaluate the relative susceptibility of 15 lentil cultivars and one breeding line to white mold under field conditions. Four cultivars were found to be very susceptible and should be avoided in areas where white mold is suspected to be a problem. There are seven test entries (six cultivars and the breeding line) showed little disease and appeared to be relatively resistant to white mold.
Technical Abstract: The relative susceptibility to Sclerotinia white mold for 15 cultivars and one breeding line was evaluated at the Spillman Farm of Washington State University in Pullman, WA. The plots were inoculated twice. First inoculation was on 12 June using cold-treated sclerotia recovered from dry pea screenings. A second inoculation was carried out using colonized oat kernels on 1 July. Disease severity ratings were taken on 9 July and again on 25 July according to the following 0-to-8 scale: 0 = no infection, 1 = 1-3% infection, 2 = 4-10%, 3 = 10-25%, 4 = 25-50%, 5 = 50-75%, 6 = 75-90%, 7 = 90-97%, and 8 = 97-100%. Because of the dry summer, white mold disease severity was generally low. Nevertheless, differences among the 16 test entries in response to white mold were observed. Cultivars Athena, Mason, Palouse and Pardina were clearly among the most susceptible cultivars, and should be avoided in fields where white mold is suspected to be a problem. Seven of the tested entries (6 cultivars and one breeding line) showed very little disease and appeared to be relatively resistant to white mold. None of the test entries were immune to white mold.