Maejo International Journal of Science and Technology (May 2010)
Phenological observation and population dynamics of six uncommon medicinal plants in the grasslands of Nilgiris, Western Ghats, India
Abstract
Phenological observation and a population density study for six uncommon medicinal plant species were made in four grasslands in Nilgiri Biosphere Reserve, Western Ghats, viz. Thiashola, Korakundah, Ebbenadu and Wenlockdown, at monthly intervals from April 2007 to March 2008. The six plant species were Anaphalis elliptica DC. (Compositae), Ceropegia pusilla Wight & Arn. (Asclepiadaceae), Hedyotis articularis R. Br. ex G. Don (Rubiaceae), Heracleum rigens Walli. ex DC. (Umbelliferae), Leucas vestita Benth. (Lamiaceae) and Luzula campestris (L.) DC. (Juncaceae). Generally, all six species exhibited peak bud formation between February and May and bud break in June. Most of the leaves were produced in a single flush. Leaf expansion continued up to August in L. vestita. Flowering phenophase was observed from July to October, but in A. elliptica it extended to December. The active period of fruit formation occurred during August to December for all species except A. elliptica, which was during January and February. Seed maturation and seed dispersal happened during December - February for all the species except A. elliptica which happened during May-June. The study of population dynamics shows that there was a net decrease in the population of A. elliptica, L. vestita and L. campestris over a period of one year at Korakundah, Ebbenadu and Wenlockdown grasslands. C. pusilla, H. articularis and H. rigens maintained their populations at the same level in the respective grasslands without any major change during the study period.
