Rendimiento de tres tipos de cruzas entre genotipos silvestres y cultivados de frijol (Phaseolus vulgaris L.)

the objective of the research was to during 2000 an experiment was established at campo experimental valle de mexico, instituto nacional de investigaciones forestales, agricolas y pecuarias (inifap) in which three of each type of cross made between a cultivated and three wild genotypes were evaluated: simple cross, backcross one and simple crosses with double recombination. the cultivated parent was the cultivar negro tacaná and the wild populations were from different geographical origin, hidalgo, puebla and jalisco. the trial was established on june 12, 1998 and conducted under rainfall plus suplemental irrigation. a complete random desing with three replicates was utilized and the experimental plot consisted of three rows 5 m in length separated 0.8 m. in all segreganting populations there were late flowereing and maturing plants, but with a larger frequency in those populations derived from simple crosses with double recombination. plants derived from backcrousses, as it was expected, displayed similar phenological and morphological traits as the recurrent parent, negro tacaná. significant differences were observed among populations for seed yield in g m2; those populations derived from backcrosses showed a seed yield similar to the recurrent parent, negro tacaná. among the simple crosses, the one derived from negro tacaná x wild hidalgo displayed a seed yield similar to the one of the cultivated parent (259 g m2). in all populations the were individual plants that showed superior yield than those of negro tacaná, i. e. transgressive segregants. in regard to seed size, few individual plants showed a larger size than negro tacaná, the cultivated parent. in all crosses a negative transgressive segregation was observed for seed size, in other words there were plants with smaller seed size than the wild parent. from the results it seems that the best type of cross for the utilization of wild germplasm in breeding the common bean is the backcross.