INFLUENCE OF SOME AGRONOMIC CHARACTERS ON THE YIELD OF SUNFLOWER SEED

Abstract

For the genetic manipulation of the seed yield components, it is necessary to know how these characters affect seed yield. In this study, 23 sunflower (Helianhus annuus L.) genotypes were evaluated in Saltillo, Coahuila, in 1987. A randomized complete block design with three replications was used. The following variables were registered: days to flowering, 100 seed weight, days to physiological maturity, plant height, and head diameter. Their influence on seed yield, by using path analysis, was also analysed. Head diameter had a highly significant and positive phenotypic correlation with seed yield. None of the genotypic correlations
were significant, but head size and days to physiological maturity were highly associated with seed yield. lt was found, by path analysis, that days to flowering had the highest direct effect on seed yield. On the other hand, days to physiological maturity had a high and negative direct effect on seed yield. The path analysis also indicated that the correlation between head size and seed yield was mainly due to its direct effect.