Research and Evaluation of the Anti-adversity and Cloning Competitiveness Ability of Rhus Typhina
|School||Shandong Agricultural University|
|Keywords||Typhina Locust Clone competition Drought Stress Salt and Drought cross stress|
Torch tree native to North America, the introduction and China in 1959. Present to the north of the Yellow River basin provinces (regions) more cultivated, mainly for the saline-alkali wasteland of barren hills and green doubles as a scenic forest tree species, to meet the greening, landscaping needs; but because it has a strong breeding competitiveness, many experts believe should not be excessive growth of even considered harmful invasive species. To this article torch tree species were taken for the study, a field investigation and pot experiment, papers were studied from two aspects, one is the the alien species torch tree clones competitiveness; second is its resilience characteristics, system study the the Torch of tree clones law and stress resistance. An attempt was made to arrive at a comprehensive conclusion to guide the torch tree in ecological construction. Torch tree growth characteristics and its clone seedlings clonal reproduction system of indicators survey Torch tree clone competitiveness. The results show that with the increase in the diameter at breast height of torch tree mother plant, root diameter, tree height, crown, crowns weight, dry weight, and other indicators showed an upward trend; With the extension of the torch tree growth years, the ability to clone the stronger but when the torch tree reaches a certain roughness began to appear after automatically quit phenomenon, the clone will decline; clone spacing mother plant distance farther the roots more stout, more robust growth. On the other hand, the torch tree intraspecific competition, planting density increases, intraspecific competition, increased populations of individuals within size class differences. Torch tree through allelopathy reduced by the number of plants to reduce competition with tree seedlings, saplings survived growth. Stumping, the torch tree stumps processing, the Torch tree growth trend is clearly strong; of torch tree and locust species showed a strong competitive advantage, the number of cloned seedlings, root diffusion distance is much larger than the locust; extremely poor site conditions, excellent the vegetative propagation characteristics of survival and rapid canopy. Torch and locust trees to drought have a strong self-control, you can quickly adjust their own metabolism, make the physiological response. The persistent drought stress, with increasing stress intensity changes in physiology torch trees and locust seedlings. SOD activity increased with the increase of the stress intensity within a certain range, after 14 days, as the stress intensity increases dramatically reduced. POD activity with increasing stress intensity the increase Hunzai case showing a trend first and then decreased with the increase of the stress intensity. Soluble protein content with the stress intensity increases does not change the law. The study found that the torch tree Salt and Drought Stress exhibit different regularity. Salt drought stress increase in the number of days increased the relative conductivity of the torch and locust trees, which typhina elevated conductivity increase membrane permeability is weaker than the locust; Salt and Drought cross under the torch and locust trees SOD activity first increased and then downward trend with time, salt and drought stress more strongly, the smaller the SOD activity increased with the severity of stress, torch tree SOD activity was significantly higher than the locust; days with salt drought stress extended torch and locust trees POD activity upward trend, the greater the salt concentration, the smaller the increase, higher than the locust torch tree initial POD activity; typhina content in the initial phase, followed by a sharp decline, after a slight upward trend ; locust showing a decline in the trend - rising - falling; 2 species PRO content are appear first decreased and then increased by the trend, declining typhina PRO content stress the number of days late in the locust; torch tree CHLA content presented first increased and then decreased trend , reached a peak on day 7, locust upward trend in; early Chlb increased, and then decreased, and increase the amplitude decreases with the increase in salt concentration and the number of days the extension, the decrease of the amplitude increases, carotenoids changes in the difference between the two species, and there is a big difference between the treatments.