CORRELATION BETWEEN SUSCEPTIBILITY TO FUSARIUM WILT AND AGRONOMIC AND TECHNOLOGICAL TRAITS IN SOME COTTON GENOTYPES

Abstract

Field trials were carried out at Giza Agricultural Research Station in 2012 and 2013 growing seasons. In 2012, 50 cotton genotypes were self-pollinated. In 2013, the genotypes were grown in a randomized complete block design with thre replications. A random sample of four guarded plants of each genotype was randomly chosen from each plot to determine some agronomic and technological traits. The agronomic traits were boll weight (g), seedcotton yield (g/plant), lint yield (g/plant), and lint percentage. The technological traits were fiber length at 2.5 % (mm), fiber length uniformity ratio (%), micronaire reading and fiber strength (g/tex). The genotypes were screened, under greenhouse conditions, in 2014 against a mixture of 50 isolates (race 3) of the wilt fungus. Incidence of Fusarium wilt was used as criterion to evaluate the reactions of the tested genotypes to the disease. The genotypes showed a narrow range of reactions to Fusarium wilt incidence ranging from 0 to 19.99 %. Of the tested genotypes, 54, 40 and 6 % were classified as highly resistant (wilt incidence was 0 %) resistant (wilt incidence ranged from 3.33 to 6.66 %), and susceptible (wilt incidence ranged from 13.33 to 19.99 %), respectively. Linear correlation coefficient was calculated to measure the degree of association between wilt incidence and each of agronomic and technological traits. Cluster analysis was used for grouping the genotypes based on the profiles of their agronomic and technological traits. Correlation and cluster analysis showed a lack of correlation between wilt incidence and each of agronomic and technological traits. This result suggests that breeding for Fusarium wilt resistance in cotton will not negatively affect the quality of agronomic or technological traits.