Provenance Differences for Fire-assistant and Fire-resistant Chemical Components in Fresh Leaf of Schima superba
- Received Date: 2004-03-29
Abstract: In fire risk period, l5 provenances of Schima superba was selected to study the geographic differences and its variation patterns for fire-assistant and fire-resistant chemical component in fresh leaves. The results indicated that there were significant differences among provenances for five main chemical components including water content, percentages of lignin,ash,crude fattiness, benzene-ethanol extractive, whose differences between highest and lowest provenances were reached 5%, 31%, 80%, 66% and 33% respectively.A classical latitude clinal variation pattern was found for the 5 main chemical component aboved-mentioned.In addition, lignin and crude fattiness content were related to the longitude of the seed source. Comparing with provenances from the northern, there were more fire-resistant component content (water and ash content) and less fire-assistant component (crude fattiness and benzene-ethanol extractive content) for provenances from the southern. The lignin, as a fire-resistant component with heavy heat value when firing, was found to be related positively to the latitude of the seed source, whose geographic variation pattern was different from water and ash content. Associated with results form the provenance trial at seedling stage, it was primarily concluded that the southern provenances were more resistant to fire with higher growth rate, richer roots and more leaves, more fire-resistant and less fire-assistant chemical components in fresh leaves.