Seena S, Sridhar K R
Department of Biosciences, Mangalore University, Mangalagangotri, Mangalore 574 199, Karnataka, India.
Can J Microbiol. 2004 Dec;50(12):1015-21. doi: 10.1139/w04-094.
Endophytic fungi of 3 age classes (seeds, seedlings, and mature plants) and 5 tissue classes (cotyledons, seed coats, roots, stems, and leaves) of coastal sand dune legumes Canavalia cathartica and Canavalia maritima were assessed by plating surface-sterilized segments on malt extract agar. Forty-six fungal taxa comprising 6 ascomycetes, 33 mitosporic fungi, 2 zygomycetes, and 5 sterile morphospecies were recovered. There was no significant difference in the colonization frequency of endophytes between plant species (p = 0.4098, Student's t test). Among the age classes, endophytic fungi colonized over 90% of seedlings and mature plants. Similarly, among tissue classes, endophytic fungi colonized over 90% of root, stem, and leaf segments. Diversity and richness of endophytic fungi were higher in C. cathartica than in C. maritima. Rarefaction curves revealed a "higher expected number of species" in mature plants of C. cathartica and seedlings of C. maritima, whereas it was highest in leaves of both plant species. The most dominant endophyte, Chaetomium globosum, colonized over 50% of the root, stem, and leaf segments of C. maritima and over 50% of the root segments of C. cathartica. The colonization frequency of C. globosum was found to be 5%-12.5% in seeds and increased up to 40%-64.4% in seedlings or mature plants. Halosarpheia sp. was the only marine fungus recovered among the endophytes.
通过将表面消毒的切段接种在麦芽提取物琼脂上，对滨海沙丘豆科植物刺桐和海滨刺桐3个年龄阶段（种子、幼苗和成熟植株）以及5种组织类型（子叶、种皮、根、茎和叶）的内生真菌进行了评估。共分离出46个真菌类群，包括6个子囊菌、33个丝孢菌、2个接合菌和5个不育形态种。植物物种间内生真菌的定殖频率没有显著差异（p = 0.4098，学生t检验）。在年龄阶段中，内生真菌定殖于90%以上的幼苗和成熟植株。同样，在组织类型中，内生真菌定殖于90%以上的根、茎和叶切段。刺桐内生真菌的多样性和丰富度高于海滨刺桐。稀疏曲线显示，刺桐成熟植株和海滨刺桐幼苗中“预期物种数更高”，而在两种植物的叶片中最高。最主要的内生真菌球毛壳菌定殖于海滨刺桐50%以上的根、茎和叶切段以及刺桐50%以上的根切段。发现球毛壳菌在种子中的定殖频率为5%-12.5%，在幼苗或成熟植株中增至40%-64.4%。盐孢霉属是内生真菌中唯一分离出的海洋真菌。
