Relationship between Fusarium Wilt Disease and Fatty Acids Content of Cottonseed

Abstract

Ten genotypes of cotton were evaluated for resistance to Fusarium wilt cause by Fusarium oxysporum f. sp. vasinfectum. The genotypes were divided into two groups based on their reactions to the disease. The first group included five susceptible genotypes (9/2017, 32/2017, 58/2017, 63/2017, and 68/2017) and the second group includes the other five resistant genotypes (123/2017,131/2017, 133/2017, 135/2017, and 137/2017). Diseases incidence in the first group ranged from 83.33% to 100%, while it ranged in the second group from 0% to 20%. Cottonseeds of genotypes contained twenty-two distinct fatty acids. Eight fatty acids (archidic, palmitic, stearic, linoleic, linolenic, myrsitic, oleic, and vaccinic) were found in different amounts in all the tested genotypes. Five fatty acids (capric, caprylic, heptadecenoic, pentadeceonic, and tetradecenoic) were found only in the resistant genotypes. Percentage of saturated acids in cottonseed genotypes was 31.719%, while unsaturated acid was 67.001%. Positive significant correlation was found between Fusarium wilt incidence and each of arachidic acid and behenic acid. Negative significant correlation was found between disease incidence and each of heptadecenoic and pentadecenoic acid. Cluster analysis showed that fatty acid profile was unable to differentiate among cotton genotypes based on their reaction to Fusarium wilt. However, fatty acid profiles differentiated among some genotypes regardless of their reactions to Fusarium wilt disease. Therefore, fatty acids could be used in seed purity tests.