جداسازی و شناسایی چند گونه از قارچ های اندوفیت همراه بذر لوبیا در ایران

Endophytic fungi are microorganisms with the ability to colonize plants for the entire or at least a significant part of their life cycle asymptomatically and in most cases have positive effects on their host. Every plant species is one host for at least one or many endophytic fungi. This group of fungi is omnivorous and has high biological diversity. However, until now, an accurate estimate of the biodiversity of endophytes has not been provided in most regions of the world as well as in Iran. In order to identify of seed endophytic fungi from 31 seed samples including Kidney bean (cultivars of Ofogh, Dadfar and Yaghut), Navy bean (cultivars of Shokoofa, Pak and Almas) and Pinto bean (cultivars of Koosha, Saleh, Sadri and Ghaffar) collected from fields of the provinces of Markazi and Lorestan were sampled according to the International Rules for Seed Testing (ISTA). To isolation of fungi, number of 400 seeds of each sample, after washing with water and surface sterilization with 1% sodium hypochlorite solution and were placed on different agar media with alternating 12 hours light and 12 hours darkness at 25 ± 1 °C. Purification of fungal colonies was performed using single spore and hyphal tip methods on 2% water agar medium. The morphological and molecular characteristics (one of the marker genomic regions including ITS-rDNA, Tef1-α, Gapdh or Rpb2 based on the studied fungal genus) of the obtained fungal isolates were examined and the species were identified. A total of 18 isolates belonging to 5 fungal genera were obtained. Molecular identification of the selected isolates and evaluation of their antagonistic effects under greenhouse condition are in processing. Based on a combination of morphological features and sequencing data, five isolates belonging to the Penicillium oxalicum, one isolate belonging to Alternaria alternata and Trichoderma virens in Kidney bean seed samples, two isolates belonging to the Fusarium oxysporum, one isolate belonging to A. alternata, F. solani and Aspergillus fumigatus in Navy bean seed samples, and four isolates belonging to the A. alternata, three isolates belonging to the Fusarium oxysporum and two isolates belonging to the F. solani were identified. The genera Fusarium (42.1%) and Alternaria (31.6%) had the highest and lowest frequency, respectively. The highest frequency of isolated fungi in the seed samples was related to the A. alternata. Since the species of this genus include pathogens, saprophytes and endophytes, in order to understand the correct relationship between this isolate and the host plant, pathogenicity tests of the isolate obtained on bean are under consideration.