بررسی قارچ‌های بذرزاد همراه با توده‌های بومی بذر زیره سبز، گشنیز، آویشن، سیاهدانه و رازیانه

Seed-borne fungi are known as one of the most important factors that threatens the health of seeds, and lead to reduce germination and vigor indices and finally reduce production. In order to evaluation of status of seeds infected in native seed populations of some medicinal plants to seed-borne fungi during the crop year 2020 from seed populations collected from fields of Cumin, Coriander, Thyme, Fennel and Black cumin were sampled according to the International Rules for Seed Testing (ISTA) and were transferred to the National Seed Health Laboratory. For isolation of fungi, 400 seeds of each sample, after washing with distilled water and surface sterilization with 1% sodium hypochlorite solution, using the standard method of determining the seed health including culture on different agar media, including Potato Dextrose Agar (PDA) and Potato Carrot Agar (PCA) were investigated. Purification of fungal colonies was performed using single spore and hyphal tip methods on 2% water agar medium and fungi were identified based on morphological characteristics and valid identification keys. According to the results, the highest percentage of natural infected in seed populations of Cumin were belong to the native populations collected from Mashhad (91.1%), Quchan (6.7%) and Fariman (2.1%), in seed populations of Coriander were belong to the native populations collected from Boshravieh (62.5%), Sarbisheh (25%), Qaen (12.5%), Karaj (0%), Arak (0%) and Qazvin (0%), in seed populations of Black cumin were belong to the native populations collected from Gorgan (47.2%), Semirom (23.5%), Fereydan (17.6%), Shahreza (11.7%), Bushehr (0%), Sarvabad (0%), Nazarabad (0%), and also in seed populations of belong to the native populations collected from Aliabad (60.6%), Nahavand (18.2%), Khodabandeh (12.1%) and Marivan (9.1%), respectively. Not detected any fungal infection in Thyme seed populations. Specific primers reported by other researchers including FOR1/FORF1, Fs4R/Fs4F, AaR/AaF and ABR/ABF were used to detect species of Fusarium oxysporum, F. solani, Alternaria alternate and A. burnsii, respectively. In general, from fungal isolates isolated based on morphological and molecular characteristics, 35 isolates belonging to A. alternata, 4 isolates belonging to A. burnsii, 5 isolates belonging to F. oxysporum and one isolate belonging to F. solani in Cumin seed populations, 8 isolates belonging to A. alternata in Coriander seed populations, 16 isolates belonging to F. oxysporum and one isolate belonging to F. solani in Black cumin seed populations and 20 isolates belonging to A. alternate and 13 isolates belonging to F. oxysporum in Fennel seed populations were identified. Overall the highest frequency of isolated fungi was related to the genus Alternaria. The results of this study can be used to complete the basic information for identifying of seed-borne fungi of medicinal plants and help to writing the national seed health standard.