Evaluation of soybean genotypes for resistance against soybean cyst nematode Heterodera glycines

Soybean cyst nematode (Heterodera glycines) is the most important factor in reducing the yield of soybean crop (Glycine max) in most of its cultivated areas in the world and is also spread in Iran in Mazandaran and Golestan provinces. In the present study, the reaction of 100 genotypes and soybean cultivars in the seed bank of Oilseeds Research and Development Company to soybean cyst nematode was evaluated. Genotypes were studied in a randomized complete block design with three replications under constant greenhouse temperature conditions. The race of soybean cyst nematode population was determined and identified using differential soybean cultivars. The results showed that 12 genotypes among Leflor, Bedford and Forrest as resistant ; three genotypes including Chiquita, Centennial and Cloud as moderately resistant ; 26 genotypes as moderately sensitive and 59 genotypes namely Essex, Faur and Clark In addition susceptible check (Jk cultivar) as highly sensitive genotype to race 3 of soybean cyst nematode were identified. The results of cluster analysis based on nematode resistance, maturity group, seed color and umbilical color divided the genotypes into five groups. The most susceptible genotypes were in the second cluster group and the most resistant genotypes were in the third cluster group. Also, most of the resistant genotypes in terms of soybean maturity group belonged to groups V and VI of the maturity group.