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PRINT ISSN : 2319-7692
Online ISSN : 2319-7706 Issues : 12 per year Publisher : Excellent Publishers Email : editorijcmas@gmail.com / submit@ijcmas.com Editor-in-chief: Dr.M.Prakash Index Copernicus ICV 2018: 95.39 NAAS RATING 2020: 5.38 |
Integration of optimal photosynthetic photon flux density (PPFD) and mycorrhization under in vitro conditions appears to have significant synergistic effect in enhancing the growth and survival of the medicinal orchid, Dendrobium chrysanthum under in vitro and ex vitro conditions. PPFD at 60 µmol m-2s-1 was found to be optimal for root colonization for mycorrhizal association by fungi (73% colonization). The growth of mycorrhizal plantlets was observed to be superior at 60 µmol m-2s-1 PPFD as compared to plantlets subjected to either lower or higher PPFD. The growth responses in terms of shoot length, leaf area, fresh weight (FW) and dry weight (DW) of mycorrhizal plantlets were consistently and significantly higher at 60 µmol m-2s-1 PPFD after 30, 60 and 90 days of treatment. PPFD affected development of stomata with increase in number of stomata per unit area of leaf with increasing light intensity. Maximum length of stomata was observed in mycorrhizal plantlets at 60 µmol m-2s-1 PPFD but light intensity did not cause any substantial effect on width of stomata. After 120 days of hardening, highest survival percentage (97.33%) was obtained with mycorrhizal plantlets transferred from 60 µmol m-2s-1 PPFD. Growth parameters observed were also higher in mycorrhizal plantlets transferred from 60 µmol m-2s-1 PPFD. Mycorrhizal association in vitro at optimal PPFD produced the most marked growth response both under in vitro conditions and during ex vitro acclimatization.