ASSESSING PHENOTYPIC DIVERSITY OF CUCURBITA PORTUGUESE GERMPLASM

Cucurbita is considered one of the most variable genera in the entire plant kingdom with regard to fruit characteristics (colour, size and shape). The most important species are: C. maxima, C. pepo, C. argyrosperma, C. ficifolia and C. moschata. In Portugal, the production of Cucurbita spp. is based in local populations and is mainly for self-consumption (human food or animal feed) and sale on local markets. The aim of this work was to characterize 108 populations of Cucurbita being55 of C. pepo, 32 of C. maxima and 21 of C. moschata. A total of20 traits (13 qualitative and seven quantitative) were scored according to the Minimum Descriptors for Cucurbita spp. developed by the ECPGR Working Group on Cucurbits were used. The C. pepo populations revealed the highest mean values for fruit length, skin thickness and seed weight, and the populations of C. maxima showed the highest mean values for fruit width and 100 seed weight. The C. moschata populations presented the highest mean values for fruit weight and flesh thickness. ANOVA revealed significant differences for all traits, with exception of skin thickness. Principal Component Analysis showed that the three most informative principal components explained 52.5 % of the total variation and a clear separation of the three species. The results reveal a high variability in this collection ofCucurbita populations.