Abstract

M. A. Yeboah, V. Katoch, R. Rakoto-Herimandimby, A. Rahantanirina and B. Rakotoarisoa

Summer squash (Cucurbita pepo L.) is one of the most popular vegetables in Madagascar, where it is grown for both leaves and fruit. Previous breeding efforts concentrated solely on high fruit yield. In recent years the demand for varieties that can produce edible fresh leaves and high fruits yield has increased. Our objective in this study was to evaluate the effects of leaf harvest and season on fruit yields of summer squash genotypes in Madagascar to identify dual-purpose varieties for the hot-dry and rainy seasons. Two leaf harvest regimes (‘no leaf harvest’ and ‘leaf harvest’), five entries (four summer squash inbred lines S16, S17, S18 and S19, and one local variety ‘Vang’) and two seasons (hot-dry and rainy) were tested in a randomized complete block design with three replications in Madagascar. The results showed entry effect was significant on yield and fruit length but not on fruit size. Interactions of all the three factors (entry, leaf harvest, and season) were highly significant in all three traits. In the rainy season, significant differences in mean yield occurred between S16 and the local check ‘Vang’ when leaves were harvested. The percentage in fruit yield reductions between the ‘no leaf harvest’ and ‘leaf harvest’ treatments were 45% for S18, and 22% for ‘Vang’ in the hot-dry season trial, and 15 and 2% reduction in the rainy season for S18 and ‘Vang’, respectively. S16 gained 3 and 9% in yield when leaves were harvested in the hot-dry and rainy seasons, respectively. Any of the entries will produce good yield in the hot-dry season, while entries S16 and S19 are recommended for high yield in the rainy season for leaf harvests in Madagascar’s subhumid tropics.