نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه گیاهپزشکی، دانشکده تولید گیاهی، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران
2 گروه گیاهپزشکی، دانشکده کشاورزی، دانشگاه ولیعصر (عج) رفسنجان، رفسنجان، ایران
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Introduction: Wild species of the Poaceae family cover a significant portion of the rangelands in Golestan Province, Iran. Arbuscular mycorrhizal fungi (AMF) are one of the most beneficial soil microorganisms that form a mutualistic symbiotic relationship with the roots of most vascular plants. These fungi enhance water and nutrient uptake (particularly phosphorus) and increase host plant tolerance to various biotic (e.g., pathogens) and abiotic stresses (salinity, drought, heavy metal contamination and nutrient deficiencies), thereby providing considerable ecological and economic benefits. This study aimed to determine the spore population, mycorrhizal colonization percentage and identity of the dominant arbuscular mycorrhizal species associated with wild Poaceae in selected rangelands of Golestan Province.
Material and methods: The sampling was conducted at a depth of 5 to 30 cm from the rhizosphere of perennial rye-grass (Lolium perenne L.), blue barley (Hordeum glaucum S.), common wild oats (Avena fatua L.), Bermuda grass (Cynodon dactylon P.), poa or winter grass (Poa annua L.), lesser canary grass (Phalaris minor R.) and woolly brome (Bromus tomentellus B.) in the northern (April 2022) and southern (July 2022) rangelands of Golestan Province. Roots were stained using lactoglycerol blue solution and the mycorrhizal colonization percentage was assessed using 20 root segments per sample. Spores of arbuscular mycorrhizal fungi were extracted by wet sieving and sucrose centrifugation methods, and spores were counted per three grams of soil with three replicates. Dominant spore identification for each plant species was done based on morphological characteristics (shape, color, size, spore wall structure, hyphal attachment, etc.) using identification keys and reliable websites.
Results and discussion: The microscopic observations confirmed mycorrhizal symbiosis in all root samples. The percentage of mycorrhizal colonization varied between different plant species (17% to 95%) and the highest and lowest colonization percentages were observed in A. fatua (95.30%) and P. annua (17.25%), respectively. The average spore population (per three grams) of Ph. minor, A. fatua, H. glaucum (Agh Abad), H. glaucum (Chapar Quymeh), C. dactylon, B. tomentellus, L. perenne and P. annua were respectively estimated at 206.67, 374.33, 278, 256, 344, 242.67, 46.33, and 324.66. A. fatua and L. perenne exhibited the highest and lowest spore population, respectively. Statistical analysis revealed a positive correlation between the number of spores and the percentage of mycorrhizal colonization in all plants, except P. annua. Based on morphological criteria, Funneliformis mosseae was the dominant species of C. dactylon, A. fatua and H. glaucum (Chapar Quymeh), and F. geosporus, Septoglomus constrictum, Claroideoglomus etunicatum, C. lamellosum and Scutellospora calospora were identified as the dominant species in H. glaucum (Agh Abad), Ph. minor, B. tomentellus, P. annua and L. perenne, respectively. These identified arbuscular mycorrhizal fungi have been previously reported in various crops and regions across Iran.
Conclusion: These findings highlight the widespread and diverse symbiotic associations between arbuscular mycorrhizal fungi and wild Poaceae species in Golestan rangelands. Variation in colonization and spore population reflects the significant influence of ecological and edaphic factors on arbuscular mycorrhizal fungi community structure. The identification of native isolates of arbuscular mycorrhizal fungi provides a critical first step towards mass production and their future utilization in restoration programs, particularly in arid and semi-arid rangeland ecosystems.
کلیدواژهها [English]
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