ARBUSCULAR MYCORRHIZAL FUNGI FROM SOME COASTAL PLANTS OF KARACHI (PAKISTAN (original) (raw)

Fourteen species of angiosperms belonging to 11 genera and 8 families were tested for their association with AM fungi in their roots and rhizospheres in Hawkes Bay coastal environment of Karachi, Pakistan. Thirteen species of AM fungi belonging to four genera were found to associate with the angiosperms. Among these fungi, Genus Glomus was the most dominant genus – represented by nine species. The maximum number of AM fungi (8) associated with a legume, Lotus garcinii, followed by a composite Launaea resedifolia (7 AM fungi) and a grass Aeluropus lagopoides (7 AM fungi). The lowest number of AM fungi (2) associated with Atriplex griffithii and Avicennia marina. Each of the 14 species tested for AMF occurrence had at least association with one Glomus species. The number of Glomus species associated with some angiospermic species was quite substantial. The frequency of occurrence of AM fungi with the angiospermic species, Glomus macrocarpum was the most frequent fungi (57.14%), Glomus epigaenum and Gigaspora geosporum associate with 7 angiospermic species each. (Freq: 50%). Glomus leptotichum and Gigaspora margarita associated with 6 species each (Freq: 42.86%) and Glomus mossaee, Acaulospora laevis and A. birecticulata had frequency of 35.71% (association of each AM fungi with five angiospermic species. The number of AMF spores per 100 g rhizospheric soil of angiospermic species varied substantially (CV: 48.7%) amongst the species tested and averaged to a grand mean of 400.31 ± 52.09 spore. The number of AMF spores were lesser than the grand mean in case of Cyperus longus, Indigofera argentea, Ipomoea pes-caprae, Heliotropium subulatum, Heliotropium sp. and Suaeda sp. whereas the number of AMF spores were near equal to grand mean value in case of species viz. Aeluropus lagopoides, Atriplex griffithii and Suaeda fruticosa. The number spores were considerably larger than the grand mean value in A. marina, C. cretica, L. resedifolia, L. garcinii, and Cyperus sp. Root colonization (%) also varied substantially amongst the angiospermic species (CV: 49.59%) and averaged to a grand mean of 22.40 ± 2.97. Root colonization happened to be lesser than the grand mean value in Atriplex griffithii, Cyperus longus, Indigofera argentea, Ipomoea pes-caprae, Heliotropium sp., Launaea resedifolia and Suaeda sp. and substantially larger than the grand mean value in Aeluropus lagopoides, Avicennia marina, Cressa cretica, Heliotropium subulatum, Lotus garcinii, Suaeda fruticosa, and Cyperus sp. The mean number of AMF spores per 100 g rhizospheric soil was quite larger in magnitude in Families Leguminosae and Asteraceae and somewhat equally moderate in Families such as Convolvulaceae, Chenopodiaceae, Cyperaceae and Poaceae. AMF clusters were recognized by Ward method of Hierarchical clustering – each cluster was a collection of highly similar species. Cluster A: Glomus clariodeum + Glomus geosporium; Cluster B: Gigaspora margarita; Cluster C: Glomus epigaenum + Acaulospora birecticulata + Scutellospora dipapillosa; Cluster D: Glomus scaledonium + Glomus leptotichum; Cluster E: Glomus mosseae + Glomus intraradices; Cluster F: Glomus clariodeum + Glomus macrocarpum + Acaulospora laevis The following seven clusters of angiospermic species were recognized on the basis of presence or absence of AMF species. Each cluster was a collection of closely similar species. Cluster A: A. marina + S. fruticosa; Cluster B: Ipomoea pes-caprae + Cyperus longus; Cluster C: Cressa cretica + Heliotropium sp.; Cluster D: Lotus garcinii; Cluster E: Indigofera argentea + Suaeda sp., Cluster F: Launaea resedifolia + Cyperus sp.; Cluster G: Atriplex griffithii + Heliotropium subulatum + Aeluropus lagopoides.