Resistance of Vitis germplasm to anthracnose in Southern Brazil

Abstract

Abstract Anthracnose is a fungal disease that affects all parts of grapevine in warm and humid regions of the world. The present study aimed to assess 13 Vitis spp. germplasm accessions for resistance to grapevine anthracnose, caused by E. ampelina in southern Brazil, during the 2014/2015 and 2015/2016 growing seasons. Anthracnose incidence and severity were assessed biweekly under natural infection from budburst (October – BBCH-09) until flowering (November – BBCH-63). The accessions were compared based on the following epidemiological parameters: a) beginning of symptoms appearance (BSA), b) time to reach the maximum disease incidence and severity (TRMDI and TRMDS), c) maximum disease incidence and severity (Imax, Smax), and d) areas under incidence and severity disease progress curves (AUIDPC and AUSDPC). Additionally, histological analyses and quantification of hydrogen peroxide production were conducted with the less and high susceptible accessions to anthracnose. In general, there was significant difference in estimated epidemiological parameters according to accessions. The principal parameters that differentiated accessions were Imax, Smax, AUIDPC, and AUSDPC. V. berlandieri, V. shuttleworthii, V. candicans, and Baco 1 and V. thunbergii and V. betulifolia were the less and high susceptible accessions to anthracnose, respectively. V. thunbergii and V. betulifolia showed the highest Imax, Smax, AUIDPC, and AUSDPC when compared to the less susceptible V. berlandieri, V. shuttleworthii, and V. candicans. Additionally, V. betulifolia exhibited higher cell death in leaf tissues around the E. ampelina infected points than V. shuttleworthii. The variation in susceptibility level to anthracnose among accessions can be utilized in further grapevine breeding programs.