Responses to Aluminium Toxicity Effects of Two Populations of Piptatherum miliaceum (L.) Cosson

Abstract

AbstractThe effects of different aluminium (Al) concentrations (0 (control), 5 and 25 ppm) and pH levels (4.5 and 10.0) on two Piptatherum miliaceum populations, one from a bauxite area (population 1) and the other from pasture soil (population 2) were studied. Root length of both populations was severely inhibited at 25 ppm Al concentration and pH 4.5. Positive correlations between the Al content of roots of the two populations and increasing Al concentrations and pH levels in the nutrient solution were observed. Increase of Al concentrations in nutrient solution resulted in the decrease of calcium (Ca) content of the roots of the two populations in both pH values, while potassium (K) concentrations in the roots slightly differed from those of the control. Leaf chlorophyll content increased with increasing Al concentrations and pH values of nutrient solution in population 1 but decreased in population 2.Based on relative values at different treatments of root length (R.L.), Ca and K content of roots and leaf chlorophyll content, it is concluded that population 1 is more tolerant to Al than population 2.The chlorophyll content, under Al influence, may serve to distinguish Al‐tolerant and non‐tolerant ecotypes.