Evaluation of Sunflower )Helianthus annus L.( Genotypes under Sewida governorate

Abstract

This research was carried out in Erah Research Station/ Sewida Agricultural Research Center/ General Commission for Scientific Agricultural Research/ Syria in 2020-2021. Where 10 local genotypes of the fruiting sunflower were cultivated, according to the RCBD randomized complete block design with three replications, to evaluate some developmental, morphological and productive traits, and to select the genotype that is most adapted to the conditions of the cultivation area. The following parameters were studied: number of days for germination (day), number of days to flowering (day), number of days to full maturity (day), average plant height (cm), average head diameter (cm), average head dry weight (g), average number of seeds per head (seed/ head), average seed weight per plant (g), average weight of 100 seeds (g), average harvest index %, average plant yield (g/ha), average dry weight of the plant (g), average achen/seed ratio%, In addition to the correlations between the studied traits was studied. The results of the statistical analysis showed significant differences between the studied genotypes, This is due to the difference in genotypes between the studied genotypes of sunflower, where the genotype 156105 was significantly the lowest in the mean number of days to germination, flowering and early maturity, with significant differences compared to all other studied genotypes, as the average number of days for germination was (2 days), and the number of days to flowering (51 days), and the number of days to full maturity (88 days), while the genotype 156045/1 excelled in each of the traits: seed yield (2928 g/ha), seed weight per plant (292.8 g), average head diameter  (36.89 cm), the weight of the dry head is (1669.7 g), and the number of seeds in the head is (1781) seeds. The results indicate that the two genotypes 156045/1 and 156105 were the most adapted to the conditions of the cultivation area. The results of the simple correlation analysis between the studied traits showed that there was a very strong positive correlation between the characteristic of the dry weight of the head and each of the number of seeds in it (r=0.776^**), and the yield of seeds (r=0.849^**), and a correlation was also found there is a very strong significant positive correlation between the number of seeds per head and the yield of seeds (r=0.765^**), and therefore the yield can be improved by improving the associated traits. The degree of dendrogram between the studied genotypes was also studied, depending on the developmental, morphological and productive traits, using cluster analysis, where the dendrogram was separated into two clusters, where the second cluster included genotype 156045/1, while the first cluster included the rest of the studied genotypes.