Title : Evaluation of Sunn pest resistance in bread wheat genotypes/cultivars using agronomic characteristics
The Sunn pest (Eurygaster integriceps Put.), known for causing severe decreases in wheat growth, yield and flour quality, is one of the most destructive insects in Iran. So, efforts had been made to identify wheat genotypes that are resistant to this pest. To investigate the response of wheat genotypes to the Sunn pest, we evaluated 18 bread genotypes and 2 cultivars. These genotypes/cultivars were selected based on flour quality, high yield and tolerant to drought stress. This experiment was conducted based on a randomized complete block design with three replications in Neishabur Agricultural Research Station, Khorasan-e Razavi, Iran during 2022-2023 growing season. The numbers of adult and nymph Sunn pests were counted in mid-January and one month later by randomly selecting sampling quadrat with dimensions of 0.5×0.5 m2. The studied traits were plant height, number of days to spike emergence, number of days to physiological maturity, and numbers of adult and nymph per m2. The results revealed that genotype/cultivar had significant impact on density of adult and density of nymph per m2. The highest density of adult and nymph were recorded for L9 with 4.0 and L7 with 3.83 No. per m2, respectively.
Keywords: Numbers of adult, Numbers of nymph, Sunn pests, Wheat