Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Resistance in Cucurbita pepo and Cucurbita maxima germplasm to watermelon mosaic potyvirus-2.

Abstract

Samples of 279 Cucurbita pepo and 159 Cucurbita maxima accessions (PI numbers) were screened for resistance to watermelon mosaic potyvirus-2 (WMV-2) in a glasshouse. The whole set of both Cucurbita species was substantially more susceptible to WMV-2 infection than previously evaluated responses to cucumber mosaic cucumovirus (CMV) infection. Large variation in resistance to WMV-2 among accessions was demonstrated. Forty-one C. pepo and 27 C. maxima accessions were fully susceptible. A limited number of accessions was free of visual symptoms of infection. Only two C. pepo accessions and five C. maxima accessions did not develop visible symptoms of the systemic infection on the true leaves and could be considered as highly resistant. These accessions may be useful for future breeding programmes. For both Cucurbita species, statistically significant differences in response to viral infection among groups of accessions originating from different world areas were documented. No clear relation between C. pepo fruit shape and resistance to WMV-2 was found.