Untersuchungen zur Vererbung von Resistenzeigenschaften bei Reben gegen <i>Oidium tuckeri, Plasmopara viticola</i> und <i>Botrytis cinerea</i>

Abstract

Investigations on the heritability of resistance to Oidium tuclceri, Plasmopara viticola
and Botrytis cinerea in grapes

In the years 1985-1987 investigations on progenies of interspecific crossings were carried out in order to ascertain the heritability of resistance to Oidium tuckeri, Plasmopara viticola and Botrytis cinerea (formation of stilbene). Results from testing the resistance in the field and in vitro were closeley correlated and allowed therefore to check the degree of resistance in vitro under standardized conditions. The coefficients of heritability in the narrow sense calculated for 0. tuckeri range from 0.31 to 0.51, for P. viticola from 0.26 to 0.39 and for the formation of stilbene from 0.23 to 0.26. According to these results, the resistance to 0. tuckeri is most strongly influenced by additive gene effects. The high coefficients of heritability in the broad sense lying between 0.82 and 0.95 for all the investigated characters indicate little environmental dependence.
Investigations on a seed!ing population of the Asian wild species Vitis yeshanensis point to a monogenic respectively oligogenic mechanism of resistance. The usage of this resistance for breeding purposes as a complement to the establishment of a stable horizontal resistance is discussed.