| Abstract Detail
Host/Plant Pathogen Interactions and Plant Health Management Akhavan, Alireza [1], Turkington, T. Kelly [2], Askarian, Homa [1], Legge, William G. [3], Tekauz, Andy [4], Tucker, James R. [3], Strelkov, Stephen. E. [1]. Ability of Pyrenophora teres pathotypes to overcome net blotch resistance in Canadian barley genotypes. Barley cultivars and lines resistant to net (NFNB) and spot (SFNB) forms of net blotch were evaluated against representative pathotypes of Pyrenophora teres f. teres (Ptt) and P. teres f. maculata (Ptm) at the seedling stage. Separate experiments were conducted for each form using a completely randomized block design with four replicates. All experiments were repeated. One week following inoculation, the second and third leaves of each plant were rated according to 1–10 and 1–9 disease severity scales for Ptt and Ptm, respectively. Plants with scores of 1–5 and >5, for Ptt, and 1-3 and >3, for Ptm, were scored as resistant and susceptible, respectively. The NFNB resistance in the cultivars ‘Vivar’ and ‘CDC Helgason’ was overcome by two and four of the Ptt isolates, respectively. ‘AAC Synergy’ exhibited resistance against all Ptt pathotypes examined; however, two isolates caused disease severities of almost 5, suggesting some adaptation to the resistance in this cultivar. Among the breeding lines tested for NFNB, TR253, CI9819 and TR236 were the most resistant with average disease severities of almost 3. Resistance to SFNB in ‘CDC Meredith’ was overcome by all pathotypes tested, while ‘AAC Synergy’, ‘Cerveza’ and ‘Major’ were resistant to all of the pathotypes. Among the breeding lines tested for SFNB, TR236 was the most resistant, with an average rating score of almost 4. The identification of pathotypes virulent on cultivars classified as ‘resistant’ indicates the importance of not relying exclusively on resistance as the sole approach to disease management. Log in to add this item to your schedule
1 - University of Alberta, Department of Agricultural, Food and Nutritional Science, Edmonton, AB, T6G 2P5, Canada 2 - Agriculture and Agri-Food Canada, Lacombe Research Centre, Lacombe, AB, T4L 1W1, Canada 3 - Agriculture and Agri-Food Canada, Brandon Research Centre, Brandon, MB, R7A 5Y3, Canada 4 - Agriculture and Agri-Food Canada, Cereal Research Centre, Winnipeg, MB, R3T 2M9, Canada
Keywords: barley net blotch Pyrenophora teres resistance screening.
Presentation Type: Oral Paper:Papers for Topics Session: 46 Location: Salon 2/The Shaw Conference Centre Date: Tuesday, July 28th, 2015 Time: 2:15 PM Number: 46004 Abstract ID:184 Candidate for Awards:CPS Best Student Presentation Awards |