The relationship of verticillium wilt and seed surface microflora with gossypol level in cotton (gossypium spp.)

The aim of study was determined to relationship between on the seed surface microflora and reaction to Verticillium wilt of cotton cultivars with different gossypol levels. Thirteen cotton cultivars were examined gossypol level and the seed surface microflora of the cotton in vitro. Then, these cultivars were observed susceptibility to non-defoliating (Vd11 isolate) and defoliating (PYDV6 isolate) pathotypes of Verticillium dahliae Kleb. in vivo. Cultivars we significant at (p<0.05) probability leval for level for disease intensity values in vivo and gossypol values in vitro. While the highest gossypol value was determined in Gloria cultivar (Gossypium hirsutum L.) with a 1.669 ?g mL-1and resistant control Giza 45(Gossypium barbadense L.) with a 1.343 ?g mL-1, the lowest gossypol value was found in Gossypolsuz Nazilli (0.196 ?g mL- 1) and susceptible control Cukurova 1518 (0.484 ?g mL-1) of G. hirsutum L. While the lowest of disease intensity value was observed Vd11 isolate and PYDV6 isolate in the highest gossypol, resistant control Giza 45cultivar (0.30-1.11). The highest disease intensity values were found in the lowest gossypol, Gossypolsuz Nazilli cultivar (2.24-2.82) and susceptible control Cukurova 1518 cultivar (2.00-2.63), respectively. Fungus species were isolated in high and low gossypol of cotton seeds at the same rate. © by PSP.