Study on the ecotype comparison of vetiver grass in Thailand

Vetiver grass of 28 different ecotypes were collected from the brackish water coastal areas in the southern to high mountains in northern parts of the country. These vetiver grass were identified as 17 ecotypes of Vetiveria nemoralis A. Camus (upland species) and 11 ecotypes of Vetiveria zizanioides Nash (a wetland species, 1 in the experiments of 12 different locations that were conducted to test the vetiver grass characteristics suitable for hedge development in sandy, loamy-clay and lateritic soils. The growth of vetiver grass considered were tillering, clump diameter and height at the age of 90 days after planting which started from July 27, 1992 to October 27, 1992. The experiment results showed that high growth of vetiver grass were obtained from 10 ecotypes, these were 6 ecotypes of V. nemoralis and 4 ecotypes of V. zizanioides. 30 tillers per clump and 18 tillers per clump respectively. Nevertheles the average of clump diameters were not different, that was 12 centimetre. An average height, of V. zizanioides was higher than that of V. nemoralis, 104 centimetre and 99 centimetre respectively. The eotypes suitable for hedge development in sandy soil were 4 ecotypes of V. nemoralis, Nakhon-Sawan (v7), Kampaengpet, 1 (v8), Roi-Et (v13), Rachburi (v20) and 2 ecotypes of V. zizanioides, Kampaengpet 2 (v9), Songkhla 3 (v28). The ecotypes suitable for hedge development in loamy clay soils were 5 ecotypes of V. nemoralis, Loei (v6), Nakhon-Sawan (v7), Kampaengpet 1 (v8), Rachburi (v20), Prajuabkirikhan (v22) and 2 ecotypes of V. zizanioides, Suratani (v23), Songkhla 3 (v28). The ecotypes suitable for hedge development in lateritic soils were 2 ecotypes of V. nemoralis, Loei (V6), Prajuabkirikhan (V22) and 4 ecotypes of V. zizanioides, Sri Lanka (V4), Kampaengpet 2 (V9), Suratani (V23), Songkhla 3 (V28).