Effect of Verticillium dahliae Kleb. on cotton yield and fiber technological properties

The objective of this study was to determine the effect of Verticillium dahliae Kleb. on cotton yield and fiber technological properties, relationships among to disease and seed cotton yield, fiber yield and fiber technological properties and also determine susceptible and tolerant cotton varieties. The study was conducted in the Southeastern Anatolia Agricultural Research Institute’s experimental area during 2004-2006. The experiment was arranged as a randomized split block design with four replications. Main plot consisted of infected and non-infected area, sub-plot consisted of varieties. In this study 10 different commercial cotton varieties were grown to test the verticillium wilt performance. The results indicated that there were significant differences among varieties for all of the investigated characteristics. Area differences were significant for all of the investigated traits except ginning percentage. The results of the non-infected area showed that there were decreasing with regard to foliar disease index (FDI), vascular disease index (VDI), vascular disease rate (VDR), first picking percentage, fiber fineness, micronaire and yellowness; while increasing with regard to seed cotton yield, fiber yield, fiber length, strength, elongation, uniformity, reflectance and spinning consistecy index. Only ginning percentage was unaffected from area differences. With planting cotton varieties in non-infected area there were 323.60 kg ha-1 increase for seed cotton yield and 114.50 kg ha-1 for lint yield. Disease led to a decrease (7.86%) in seed cotton yield and (6.73%) in fiber yield. The results of this study indicated that GW-Teks, GW-Golda and Carmen varieties were tolerant; while Maraş 92, Sayar 314 and Stoneville 453 were sensitive in terms of FDI, VDI and VDR and tolerant varieties can be used as parents in Verticillium breeding programs.