|Garces, Sandra - VISITING SCIENTIST|
|Koch-Dean, Margery - VISITING SCIENTIST|
Submitted to: In Vitro Cellular And Developmental Biology
Publication Type: Abstract Only
Publication Acceptance Date: June 18, 2001
Publication Date: June 18, 2001
Citation: Hammerschlag, F.A., Garces, S., Koch-Dean, M., Maas, J.L., Smith, B.J. Regenerants, derived from leaf explants of several strawberry cultivars, exhibit increased levels of resistance to the fungal pathogen colletotrichum acutatum.. In Vitro Cellular And Developmental Biology. 37:34A Technical Abstract: Regenerants, from leaf explants of strawberry (Fragaria x ananassa) cultivars Chandler, Delmarvel, Honeoye, Latestar, Pelican and Sweet Charlie, were generated on MS medium containing either 1 or 10 uM thidiazuron and 0.49 uM indole-3-butyric acid (IBA), propagated in vitro on medium containing MS salts, 4.4 uM 6-benzyladenine and 5.7 uM IBA, and 4 wk prior to screening, were transferred to propagation medium without growth regulators. Regenerants and cultivars were screened in vitro by soaking leaves from 4-wk-old cultures in a spore suspension of the pathogen Colletotrichum acutatum isolate Goff (causal agent of anthracnose) for 24 h, subculturing leaves onto 0.5 % Difco Bacto agar, and then scoring leaves for percentage infection after 7 d. Regenerants exhibited 3.5-, 1.7-, 1.7-, 2.1-, 1.4- and 3.9-fold increases in levels of disease resistance compared to cultivars Chandler, Delmarvel, Honeoye, Latestar, Pelican and Sweet Charlie, respectively. Maximum levels of resistance to C. acutatum were exhibited by regenerants CS-1 and CS-10 (from `Chandler`), and SS-3, SS-8 and SS-9(from `Sweet Charlie`). CS-1, CS-10, SS-3, SS-8 and SS-9 exhibited 17.5, 17.7, 11.7 14.9 and 13.9 percent leaf infection, respectively, compared to 62.4 and 45.1 percent for `Chandler and `Sweet Charlie`, respectively. These studies suggest differences in genetic stability among strawberry cultivars cultured in vitro, and that screening for somaclonal variation may be a feasible approach to increasing levels of disease resistance in strawberry cultivars.