Effect of ABT on Root Growth and Seedling Survival of Haloxylon ammodendron

Abstract

The effects of ABT3 on the fine root dynamics of seedlings,morphological characteristics of root system at the end of growing season and survival rate of seedlings of Haloxylon ammodendron were studied.The plants were cultivated under natural conditions with four ABT3 treatments,i.e.25,50,100 and 200 mg L-1of ABT3.A random block design was used in the experiment.The results showed that:(1) There were two growth peaks of the fine roots growth of the seedlings which appeared in June and September to October.After ABT treatment,the growth dynamics of fine roots of seedlings was consistent with the control.However,ABT treatment significantly increased the total length of fine roots,growth rate and the number of fine roots.(2) Survival rate of seedlings and root characteristics were closely related,and the regression analysis showed that the underground biomass,root volume,root surface-area,length of axial root and above ground biomass were positively correlated with the seedling survival rate.This result indicated that increasing root growth resulted in the enhancement of seedling survival rate.(3) The results of the principal component analysis suggested that the best treatment was 50 mg L-1of ABT which was inoculated in June in local areas.Fig 2,Tab 3,Ref 31