Symbiotic Effect of Arbuscular Mycorrhizal Fungi on Growth and Flowering of Micropropagated Plants of Chrysanthemum (Chrysanthemum dendranthemum)

Field mortality and poor growth of in vitro raised plantlets of chrysanthemum is a major hindrance for commercial propagation through tissue culture. In the present investigation four AMF strains namely, Acaulospora laevis, Acaulospora scorbiculata, Glomus fasciculatum and mixed AMF strains (Nutrilink®) were used as bio-hardening agents to improve survival, flower quality and yield of in vitro raised chrysanthemum plantlets of cv. Yellow Bangla. Plantlets inoculated with mixed AMF gave the highest survival (94.89%) and root colonization (66.23%). The predominant effect of mixed AM fungi was also evident as increased plant height (32.34 cm), root length (24.62 cm), leaf number (46) and leaf area (10.93 cm²) of the inoculated plantlets. Acaulospora laevis and Glomus fasciculatum were found more effective in improving both shoot and root biomass at 30, 60 and 90 days after inoculation (DAI). All the treatments a improved survival and growth significantly over uninoculated control. The plantlets inoculated with Glomus fasciculatum and mixed AMF flowered early, produced higher yield, bigger flowers with increased sugars and carotene content in the flowers than other treatments.