Seed germination in Taxus baccata subsp. wallichiana was investigated using soil from the forest as well as non-forest areas, including sterilized soil. Results obtained from various soil treatments indicated the presence of certain antigerminationfactors in the rhizosphere soil of T. baccata, which seem to be of microbial origin. Seed germination was found to improve in autoclaved Taxus forest soil. The aril portion of Taxus seed inhibited germination. Since Taxus plants were found growing underthe shade of Cedrus deodara trees, probably sharing similar rhizosphere communities, seed germination of Taxus was also tried in Cedrus forest soil, which too was found to be inhibitory. Similar to Taxus rhizosphere soil, in this case also, germination improved in autoclaved soil. Pine rhizosphere soil and non-forest soil treatments resulted in higher seed germination, indicating the absence of antigermination factors. Highest seed germination (up to 70 percent) was recorded in non-forest soil under polyhouse conditions, when the seeds were sown after removing the aril. These results are indicative of the association of specific microbial population with Taxus rhizosphere, not favouring its own seed germination. The study has implications in afforestation or reforestation programmes.
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