摘要：Iran with large saline areas is an ideal habitat for growth of plants of the family
Chenopodiaceae. Diversity, frequency, and population density of endophyte fungi species depend
on the edaphic and climatic conditions, heterogeneity of habitats and niches present within the host
tissues, as well as on the competing organisms. In order to isolate endophytic fungi, 52 specimens
of each Chenopodiaceae species were collected from its natural habitats in dry and temperate
ecosystems located in the south and north of Iran. Staining roots showed that hyphae, spore and
microsclerotia of endophytes are present in all surveyed roots. After surface disinfection, specimens
were cultured on potato dextrose agar medium (PDA). A total of 192 fungal isolates were obtained
and identified on the basis of morphological features and molecular identification. Obtained
isolates consisted of eight dematiaceous genera (Alternaria, Bipolaris, Chaetomium, Cladosporium,
Curvularia, Embellisia, Macrophomina and Ulocladium) and four non dematiaceous genera
(Acremonium, Aspergillus, Fusarium and Penicillium) and twelve types of sterile mycelia. We
isolated three species of Alternaria in the studied sites that base on phylogenetic studies located in
three different groups. Most of plant roots had a colonization rate of 100% in dry ecosystems (site
A, B), while the average colonization rate in temperate ecosystem was 63.8%. However, Shannon's
and Fisher's Alpha indices indicate diversity of fungi in temperate ecosystem (site C, 2.45) is higher
than that of in other sites. Among the genera, Fusarium was the most abundant in all ecosystems
(site A 51%, site B 49% and site C 57%). Climate and soil condition can alter frequency of
endophytic fungi in each ecosystem, so that site C with different altitude and soil condition in
temperate region had different fungal distribution patterns compared to other studied sites in arid
region. Our observations showed that higher endophytic fungi frequency can occur in the roots of
plant in arid soils with pH values ranging from 7 to 8 and EC values ranging from 1.4–4.5(dS m-1
)
in high altitude (1230–2000 m) compared to those in roots of plants in temperate soil in low
altitude (13m). According to similarly Jaccard index, site A and B had the highest similarity (0.26).
