VETIVER AGRONOMY


A Comparative Study On Growth, Rooting System And Yield Of Difference Ecotypes Of Vetiver Grass.
Viroj Satanasolvapark, Chaiwat Sittibutr and Chaleol Jeerachanya, Land Development Department, Ministry of Agricultural and Cooperatives, Bangkok, Thailand.

The comparative study on growth, rooting system, and yield of 10 ecotypes of vetiver namely Songkla 3, Sri Lanka, Kamphaeng Phet 1, Ratchaburi, Loei, Su rat Thani, Kamphaeng Phet 2, Naskorn Sawan, Prachuap Khiri khan and Roi Et was conducted at Amphur Muang, Narathiwat Province on Kho Hong soil series. The study showed that Ratchaburi gave the best performance in term of height tillering and crop yield followed by Prachuap Khiri Khan and Songkla 3.


A Global Perspective Of Vetiver
H. Zvi Enoch. ARO, Institute of Soils and Water, Dept. of Environmental Physics and Irrigation, P.O. Box 6, 50250 Bet-Dagan ISRAEL

The potential role of Vetiver grass in modifying unwanted effects of land-use-change and burning of fossil fuel is presented. In this century we have witnessed large scale soil erosion and climate changes. In the next century soil erosion and climate change are expected to be even more damaging to the well-being of mankind.

The role of Vetiver grass hedges in restricting the world wide soil erosion is outlined.
Means of restricting global warming by increasing the carbon transfer from the global atmosphere to the vadose and phreaticenes using deep-rooted plants like Vetiver is outlined.
Various techniques for improving Vetiver plant survival in cold, saline and arid conditions are presented.


Genomic Manipulation For Eco- Friendly Plantation And Enhanced Productivity Of Essential Oil In Vetiver
U.C. Lavania and Sushil Kumar. Central institute of Medicinal and Aromatic Plants, Post: CIMAP, Lucknow - 226 015, India.

Profuse seed formation enriches vetiver population in its natural habitat but leads to a heterogenous mix of in-built genetic variability that may not be always desirable. Nevertheless, the vegetative mode of propagation attendant in this species promises a distinct advantage for realising uniform population and the resultant plant products. But this does not take care of the menace that is likely to take place on account of seed dispersal, disturbing genetic purity of the growing population as well as spread of vetiver to undesired destinations, lest the flowering tops are excised before seed-set. Therefore, an eco-friendly approach should aim at isolating the desired plant types that either do not bloom or bear only infertile seeds.

In India, tremendous amount of genetic variability exists in vetiver that can be clustered into five distinct groups on account of karyomorphological characteristics and 2C nuclear DNA content (range 2.0 to 2.6 pg). Although, non flowering/infertile plant types naturally occur in southern parts of India, their genetic manipulation to attain desirable attributes is greatly handicapped for lack of an amenable reproductive system. Therefore, resorting to artificial polyploidy is the obvious choice to meet the twin objectives of genetic manipulation for bringing a desirable change in agrobiological characteristics as well as causing a breakdown in sexual reproductive system.

Curiously, the artificial autotetraploids developed in this species have shown their superiority over diploid progenitors with respect to economic yield by 60% and enhanced soil binding capacity on account of thicker roots. The seed sterility associated with such autotetraploids and the expected triploids would not only restrict their unwanted spread, but facilitate channelisation of saved biological resource of the plant towards vegetative vigour and secondary metabolism.


Dr. T. K. Sivaraj M.Sc., Ph.D., Forest ecologist
Phone . 01631 - 71535. India.

ORGANISATION . Wastelands Development Division, Centre, for Environmental Conservation and Rural Development, Dr. S. Krishnaswamypuram - 627602, Pappakudi (PO), Tirunelveli District, Tanmilnadu, India.

ABSTRACT - 1

The paper summarises research results of the use of vetiver grass to improve the water holding capacity and moisture percentage of soil in wastelands. Water holding capacity and moisture percentage are the two important soil factors governing the productivity. Vetiver grass was grown in an area with known water holding capacity and soil moisture percentage for 20 months. A control plot was maintained without vetiver grass. Soil samples were collected once in a month. in control and treated plots. Water holding capacity and soil moisture percentage were determined by standardized methods. When compared with control plots, the treated plots show 20% increase in water holding capacity & soil moisture percentage over control. Positive correlation were made between root biomass and the two soil parameters studied.

ABSTRACT - 2

Fine roots significantly influence soil organic matter accumulation and nutrient cycling. Characterization of the activity of the fine roots is therefore a key approach to the understanding of the below ground system (Singh). At the global level, fine root production represents a large and relatively unknown portion of the production/decomposition carbon balance. Despite the central importance of fine root dynamics neither a clear and consistent pattern of fine root dynamics in communities nor an understanding of factors controlling those dynamics has emerged (Aber). Very little information is available on this subject. The present study on fine root productivity of vetiver was designed to unravel temporal and spatial patterns of their size distribution, growth, decomposition and overall role in the functioning of the below ground system.

Root sampling. involved collection of replicate soil cores, hand washing and sorting of roots from the soil matrix. Collections were made at monthly intervals. Ten randomly spaced samples (1.9 cm in diameter and to a depth of 15 cm) were collected separately in the study area. (l8 months old stand of vetiver). Annual fine root production of vetiver is estimated by max-min method of McClagherty et al (1982)

The annual fine root biomass was 190 kg/ha. Positive correlation was obtained between fine root biomass and organic carbon content of soil.

ABSTRACT - 3

The paper presents the impact of R D M (Rock Dust Mineralisation) technology on the biomass production of vetiver grass. The positive impact of R D M technology was well studied and well reported in many forest tree species and vegetable crops (Joanna Camp). The technology is simple, cost effective and environmental friendly. As far as known to us this study is the first research effort made on the impact of R D M technology in the productivity of vetiver grass.

The study was carried out in earthen pots. Twenty five pots were kept without R D M treatment (control) and twenty five pots were treated with R D M treatment. Biomass (Root & Shoot) production was estimated after 120 days. Productivity of vetiver in control pot is 0.225g/day and 0.383g/day in treated pots. Significant increase in the biomass was noticed in the treated plants. Since this was only a pilot study carried out for practical application the conclusion is tentative and R D M technology needs further investigation.


Effect Of Soil Water Levels And Nitrogen Fertilizer On Growth Of Vetiver Grown On Three Major Soil Series Of Northeast, Thailand.
Santibhab Panchaban And Mongkon Ta-Oun
Department ofSoils, Faculty ofAgriculture, Khon Kaen University, THAILAND.

Experiments were conducted in greenhouse and in the field to elucidate the effect of soil water and nitrogen fertilizer levels on growth of vetiver on three major soil series of the Northeast, Thailand, namely: Satuk (Oxic Paleustults), Nampong (Ustoxic Quartzipsamments) and Roi-et (Aeric Paleaquults at Khon Kaen Province during 1993-1994).

For the greenhouse study, four levels of soil water (100, 80, 60 and 40% of field capacity) were applied with each level of 0, 2.5, 5 and 10 kg. nitrogen fertilizer per rai. three weeks old Songkla-3 vetiver seedlings were transferred into 5 kg. capacity pots. Soils were treated with respective levels of water and nitrogen. Experimental design was factorial in CRD. Plants were observed for growth and harvested at 3 months.

Roi-et soils gave the highest shoot dry matter followed by Nampong and Satuk soils. In general, increase in soil water as well as nitrogen fertilizer levels resulted in increase in shoot dry matter for all soils. There was no interaction between soil water and nitrogen fertilizer levels for Satuk and Nampong but Roi-et soils.

For field study, three soil series with three different locations were surveyed and selected. For each soil, 2 levels of soil water (control and irrigation) were applied with each level of nitrogen fertilizer (0 and 10 kg. N per rai). Plot size were 4 x 6 m. with 1 x 1 m. spacing. Experimental design was in RCBD with 3 replications. Growth was observed and measured. The plants were harvested when they were 8-10 months old. Shoot dry matter as well as other parameters were determined. In general, increase in soil water levels as well as nitrogen fertilizer resulted in increase shoot dry matter. Nampong soils gave the highest shoot dry matter followed by Satuk and Roi-et soils respectively. For Nampong soils, the effect of irrigation was extremely high for shoot dry matter when compared to the effect of nitrogen fertilizer where as on the other soils, the effect from both treatments were more or less similar.


Varietal Selection For High Root Biomass And Oil Yield In Vetiver
R.K. Lal, J.R. Sharma and H.O. Mishra, Central Institute of Medicinal & Aromatic Plants, P.O CIMAP, Lucknow-2260 15, India

Soil-erosion is a serious cause of ecological disturbances and environmental degradation. Its impact is more distressing in resource-poor countries which can hardly afford mechanical control of soil-remediation. Vetiver -- a perennial grass with its fibrous roots offers an inexpensive yet effective and eco-friendly tool to combat soil erosion. Axiomatically, the larger its root volume, better is the capacity to conserve soil and soil moisture both. Besides, larger root volume will also ensure higher (dried) root yield which has multiple economic uses including those related to aroma and essential oil, the world renowned Khus oil (oil of vetiver). With this in view, we screened 45 indigenous germplasm collections of vetiver for fresh and dry root biomass, oil content and oil yield. Sixteen clones/lines were found to be promising. They were evaluated in initial station trial, where the best five strains (BDP-1, BMH-1, MBR-5, BMH-3 and MBP-6) were shortlisted and elevated to bench scale trial (BST). The elite strain BDP-1 had the largest root-volume (dry root yield = 97.0 q/ha) followed by BMH-1 (56.2 q/ha), BMH-3 (33.3 q/ha) and MBR-5 (28.7 q/ha), all registering 12 to 3.6 times more root yield than the commercial checks in BST. Fortunately, the oil content in their roots was also high, hence economically most viable. Thus BDP-1 with its largest root volume can serve as an excellent soil-binder besides being the most productive oil strain of vetiver.