Chloride exclusion patterns in six grapevine populations

Abstract

Evidence exists for both quantitative and qualitative inheritance of chloride exclusion in Vitis species used as rootstocks. To increase the scope of these data, the patterns of chloride exclusion in six populations of Vitis progeny derived from parents with variable capacity for chloride exclusion were examined. Methods and Results: Screens were conducted using a recently developed greenhouse assay that measured chloride concentration in the leaves. Chloride uptake was distributed continuously in all of the populations. Two strong excluders showed a clear difference in exclusion capacity with the hybrid progeny equivalent to, or evenly distributed between, the parental values. Populations with the lowest mean chloride concentration in the leaves had either a V.berlandieri or V.rupestris parent. Conclusions: Chloride exclusion appeared to be inherited quantitatively in the crosses examined; however, variability in chloride accumulation among replicates of the same genotype was high enough that simple dominant inheritance could not be ruled out. Differences in chloride exclusion were found between genotypes classified as strong excluders. Significance of the Study: Differences observed between strong excluders and the even distribution of hybrid progeny at or between the parental values provides a theoretical basis for the genetic improvement of this trait.