PRODUCTION OF ADVENTITIOUS ROOTS AND BUDS ON FRAGMENTS OF MYRIOPHYLLU M SPICATUM L.

The time for adventitious roots and buds formation and the frequency of plantlet production fromwatermilfoil fragments were compared among fragments from different node?positions or with different lengths.The results demonstrated that the time for adventitious roots and buds formation was gradually shortened with the descending of node positions from the top down while the frequency of plantlet formation increased.The length of fragments (expressed by the amount of nodes on fragments) also has some effects on the time of root and bud formation as well as frequency of plantlet formation. Multi?node fragments produced adventious roots and buds in a shorter time than mono-node fragments and developed to plantlets with a higher frequency. Compared with throwing method which means throwing the cuttings into thewater randomlyl, cuttage method delayed the formation of adventitious roots and buds from the multi?node fragments, but increased the frequency of plantlet formation.