تعيين درجه ميزباني برخي ارقام سويا نسبت به تيپ غالب نماتد سيستي سويا در ايران Heterodera glycines HG Type O

EVALUATION OF SOME COMMON SOYBEAN CULTIVARS TO THE MAJOR TYPE OF THE SOYBEAN CYST NEMATODE OF IRAN, HETERODERA GLYCINES

Host suitability of 17 soybean cultivars commonly grown in Iran to the soybean cyst nematode, Heterodera glycines, was evaluated in growth chamber, greenhouse and field conditions. In pot experiments, host suitability was determined on the basis of the nematode development on the tested cultivars compared to the standard susceptible cultivar Lee 74. Reaction of the cultivars was also evaluated by growing the tested entries in a naturally infested field and determination of the nematode development on them as a ratio of the nematode development on cv. Lee 74. The nematode type categorization was determined by a bioassay test on the differential lines. All of the cultivars except DPX showed a high degree of susceptibility to H. glycines HG Type 0. None of the cultivars classified as moderately susceptible or moderately resistant. Resistance of the cv. DPX with low female index was consistant in pot and field trials.