Research on Pyrenophora tritici-repentis tan spot of wheat in Uruguay
1998
Diaz de Ackermann, M. | Kohli, M.M. (INIA, La Estanzuela (Uruguay))
Tan spot of wheat, first reported in Uruguay in 1982, did not become a major disease until 1990/91 when high disease incidence was noted in the northwestern coastal region of the country. During those years, identification of germplasm with superior disease resistance was not possible due to severe infection levels, although it was possible to distinguish between symptoms of Drechslera tritici-repentis and of Septoria tritici. Almost all cultivars under evaluation were moderately to highly susceptible to tan spot. The perfect stage of the fungus was found on wheat stubble in 1993. Many of the numerous alternative disease hosts reported in the literature are present in Uruguay; however, none have tested positively for tan spot. The increase in zero-tillage cultivation in the country has made it essential to develop and identify highly resistant cultivars. Local advanced breeding lines and introduced germplasm have been screened for tan spot resistance at key locations since 1990. Of these, Fink and other lines were found to be resistant, but Vicam was found susceptible. Careen 12 and Red Chief, sources of tan spot resistance elsewhere, were not adapted to local conditions. Newer germplasm from the region and from CIMMYT, such as Milan, Cisne INIA, Coker62/BR14, LE2062/LE2096, LE2091/LE2089, E.Dor/Aepoglom, and Kvz//BB/Cha/3/Trm/4/TEMU36-78/5/Ovacion, has shown stable resistance over years. Recently, a set of advanced lines from CIMMYT selected for high rainfall conditions has been tested at the seedling stage.
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by International Maize and Wheat Improvement Centre