Hello Sandy, >From various sources (online and in books) I have come to understand the following:
1) Most orchids need fungus to germinate. This is a fight of life and death. If the fungus is too strong, it can kill the seed. If the seed can keep the fungus in check, it survives and grows. 2) From germination, an orchid seed relies on the fungus for nutrition. This period can be long or short, depending on genera and species. Phals quickly put out leaves and can flower in about 4 years. Some slipper orchids could take many years before putting up a leaf, and many more before flowering. Also, there exist orchids who are not able to make chlorophyl at all, and rely 100% on fungus to feed them. Upon maturity, some orchids tend to eliminate fungii from their roots. Others tend to keep a colony handy. 3) Even orchids who have green leaves and produce food by photosynthesis can revert to their earlier phase of fungal dependency should conditions force them into prolonged dormancy underground. If the orchid had eliminated all fungii from its roots, it can always "invite" a new colonization. So, in bad conditions, some orchids will simply go underground and live off of fungus until it feels conditions have ameliorated above, and will put out new leaves and flowers. This is especially true of terestrial species with tubers. Epiphytes might function somewhat differently. (I got most of my information out of books on European native orchids. Some websites are cited in the following links on symbiosis between fungus and orchids). Sincerely, Marianne To see some disscussions and links: http://ukorchidforum.proboards24.com/index.cgi?board=orchidchat&action=display&num=1090921407 http://ukorchidforum.proboards24.com/index.cgi?board=orchidchat&action=display&num=1093603565
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