عوامل قارچی مرتبط با بیماری نقطه سیاه گندم در سه رقم از گندم در برخی انبارهای استان همدان

Black point disease is an important disease of wheat, which can be problematic in rainy regions during the early stages of seed growth. When the seed moisture content is more than 20% and the relative humidity of the air is more than 90%, the disease is dramatically increased. The greater the amount of blackened area in the seed, the more likely the seedling wilt and root rot will be. In this study, 30 samples of three varieties of wheat seeds including Mihan, Pishgam and Sayson according to ISTA rules were collected from 5 Hamedan province seed loads in the spring of 2016. 100 infected seeds of each sample were cultured on papers soaked with sterile water in petry dishes and then incubated at 20 °c for 8 days under alternating 12 hours of darkness and NUV light cycle. Plated seeds were screened daily under steriobinocular microscope and growing hyphae from seed margins isolated and purified by single spore techniques. The fungi were stored in refrigerated PDA media at 4 ° C. In this study, 150 fungal isolates were obtained. Isolates of each genus, according to references and valid identification keys, put on culture mediums and under identification conditions, then isolates identified based on morphological characteristics. Based on results of this study species including Alternaria infectoria, Alternaria alternata and Stemphylium sp. by 25, 16.66 and 15% were the predominant fungi and Penicillium sp., Rhizopus sp., Mucor sp. and Fusarium graminearum were minor importance species. Study of dominant mycoflour associated with black point disease in other varieties of wheat could be recommended.