草铵膦对棉花根系发育影响及其生理机制

Effect of Phosphinothricin on Growth of Cotton Seedling Roots and Its Physiological Mechanism

草铵膦(Phosphinothricin,PPT)在生产上使用后易在土壤中残留,但其对根系生长发育的影响国内尚无报道。在温室内水培条件下用不同浓度PPT处理棉花幼苗根系,研究PPT对棉花根系发育的影响及其生理机制。结果表明,当PPT浓度为1mg/L时,植株根系的总长度、面积和体积显著减小,随着PPT浓度的上升,棉花根系的总表面积、根长和体积的受抑制程度增大,当处理浓度大于5mg/L时,根系的总表面积、根长和体积的受抑制程度达到最大。随着PPT处理浓度的增加,谷氨酰胺合成酶(glutamine synthetase,GS)的活力也显著下降,从而导致铵积累,这可能是草铵膦抑制根系生长的重要原因。

After using of PPT, it was apt to accumulate, but its effect on cotton root growth was not reported at present. Therefore, this paper studied effects of different PPT concentrations on root growth and development under hydroponic cultured in greenhouse. The results showed that the total root surface area, total root length and total root volume significantly decreased when PPT concentration was 1 mg/L, to maximum at 5 mg/L concentration of PPT. The activity of glutamine synthetase was reduced significantly as the concentration of PPT increased. It maybe ammonium＇ s accumulation inhibited root growth, thus decreased the activity of root and glutamine synthetase.