摘要：Verticillium wilt (Verticillium dahliae Kleb.)is a major wilt pathogen impacting cotton farmingin Turkey.The most efficient and cost-effectivemethod of controlling the disease is the use ofresistant cotton varieties.The aim of the study wasto determine the reactions of new upland cottonvarieties (G.hirsutum L.) in Turkey against thedefoliating and non-defoliating pathotypes ofV.dahliae Kleb.randomized plot design with fivereplications was set up in the growth chamberconditions.A total of twenty upland cotton varietieswere used resistant-control Giza 75,tolerant-controlCarmen and susceptible-control Acala SJ2 varieties.Varieties were significant at (P二0.05) probabilitylevel for disease severity values in pot trial.Diseaseseverity values of the varieties were determinedhigher in PHCVd47 isolate (defoliating pathotype)than PHCVd3 isolate (non-defoliating pathotype).None of the upland cotton varieties were foundresistant in the experiment.Using PHCVd3andPHCVd47 isolates of V.dahliae,resistant-controlGiza 75 variety (0.34-0.96) had the lowest diseaseseverity and followed by tolerant-control Carmenvariety (1.52),Harem 1 (1.54),Efe (1.56),Harem 2(1.56),May 455 (1.58) and Lima (1.58) varieties inPHCVd3 isolate; tolerant-control Carmen variety(1.96),Harem 1 (2.00),Lima (2.04),Harem 2(2.04) and Efe (2.04) varieties in PHCVd47 isolate.The highest disease severity values against bothpathotypes were determined in the susceptible-control Acala SJ2 variety (3.20-4.00).
