Paris, H.S., Department of Vegetable Crops, Agricultural Research Organization, Newe Ya'ar Experiment Station, Haifa, P.O., Israel

Fordhook Zucchini, a squash (Cucurbita pepo) cultivar having intensely colored fruits conditioned by genotype D/D L-1/L-1 L-1/L-2, was crossed with Beirut, a squash cultivar having lightly colored fruits. Beirut was also crossed with Vegetable Spaghetti, a cultivar having lightly colored fruits conditioned by genotype d/d l-1/l-1 l-2/l-2, and with tester stocks of genotypes d/d L-1/L-1 l-2/l-2 and d/d l-1/l-1 L-2/L-2. The results indicated that Beirut, like Vegetable Spaghetti, possesses genotype d/d l-1/l-1 l-2/l-2. However, no F2- or backcross-generation segregates possessing the 'Light type 1' phenotype, conditioned by recombinant genotype d/d L-1/-l-2/l-2 and heretofore observed when Fordhook Zucchini was crossed with Vegetable Spaghetti, were recovered when Fordhook Zucchini was crossed with Beirut. The results of crossing Beirut with Vegetable Spaghetti and with the tester stocks indicated that both Beirut and Fordhook Zucchini carry a recessive gene, designated pl, which results in 'Plain light' fruit coloration in plants of d/d L-1/- l-2/l-2 genotype. Beirut possesses genotype d/d l-1/l-1 l-2/l-2 pl/pl, Fordhook Zucchini D/D L-1/L-1 L-2/L-2 pl/pl, and Vegetable Spaghetti d/d l-1/l-1 l-2/l-2 Pl/Pl. Both the dominant D allele and the dominant L-2 allele are epistatic to gene pl. © 1992 Kluwer Academic Publishers.