ENHANCEMENT OF DIPLOID SOLANUM-CHACOENSE BITT USING ADAPTED CLONES OFSOLANUM-PHUREJA JUZ AND BUK

F1 hybrids between Solanum phureja and S. chacoense were studied in a new approach to enhance wild diploid potato species using adapted S. p hureja clones as the female parent. S. chacoense parents had few tuber s, whereas S. phureja parents had been previously selected for tuberiz ation under long days. Twenty hybrid families were evaluated for haulm vigor, vine maturity, stolon development, frequency of tuberization, tuber set, tuber yield and average tuber weight under naturally occurr ing increasing or decreasing photoperiods in spring and fall growing s easons in Morocco. The hybrid plants were more vigorous, later maturin g with thicker stolons in the spring season. Frequency of tuberization and tuber set did not vary with season. Tuber yield and average tuber weight were higher in fall; the maximum yield was 2.4 and 4.6 kg per hill under spring and fall conditions, respectively. Remarkable variat ion was found both between and within hybrid families for all traits i n this first cycle of enhancement. The selection of vigorous, fertile clones incorporating the S. chacoense genome is possible by using S. p hureja as an adapted germplasm source.