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El objetivo de esta investigación fue estimar los parámetros genéticos de la variedad CHF1-Chapingo de tomate de cáscara (Physalis ixocarpa Brot.). Se evaluaron 200 familias de medios hermanos maternos en tres ambientes, con un diseño experimental de bloques al azar con dos repeticiones y 22 plantas por unidad experimental. La heredabilidad en sentido estricto de los 13 caracteres estudiados fluctuó entre 37.1 y 57.7 % y el coeficiente de variación genético aditivo entre 8.2 y 24.4 %; para rendimiento total estos valores fueron 37.5 y 10.4 %, respectivamente. El número y peso de frutos en el primer corte, y frutos totales por planta fueron los principales componentes del rendimiento total. Se encontraron correlaciones genéticas aditivas con valores absolutos altos del rendimiento total con: rendimiento en el primer corte (0.67), frutos por planta en éste (0.50), frutos totales por planta (0.58), número de frutos amarrados (0.38) y altura a la primera bifurcación del tallo (-0.49).

In the present work a dialelic mating design with ten varieties of different husk tomato (Physalis ixocarpa Brot.) races was made. The objectives were to study the magnitude of the heterosis between varieties, to define the heterotic pattern, and the relative importance of additive and non additive effects. Dialelic crosses were made in the fall of 1994 and 1995, and they were evaluated in two loca-tions during the spring-summer cycle of 1996. From the ten studied varieties nine of them were self-incompatibles and the other one was self-fertile; however, the self-fertile variety did not produce fertile descendants when it was crossed with the others, but those crosses induced parthenocarpy. This phenomenon was also observed in the self-incompatible varieties when they were self-pollinated. Maternal and reciprocal effects were not significant; therefore, the inheritance of average fruit weight (AFW), fruits number per plant (FNP) and total yield per plant (TYP) traits was basically nuclear. The general combining ability effects were significant in the three studied traits and the specific combining ability effects were significant just in AFW; therefore, in FNP and TYP the additive affects were more important than the non additive ones. The average heterosis of the intervarietal hybrids was significant in the three studied traits (AFW = - 5.73 , FNP = 10.42 y TYP = 17.19 %). The hybrid between the Verde Puebla and CHF1-Chapingo varieties presented more TYP (14.29 %) than the best variety and its specific heterosis effect was more important than the varietal heterosis effect, in the three.