根际中硅、铁、锰和铝的状况与水稻生长

本文以根盒试验与盆栽试验相结合的方法,研究了红壤性水稻土、淀浆白土、第四纪红土和赤红壤植稻后根际微生态系统中Si、Fe、Mn和Al等元素的状况及其与水稻生长的关系。结果表明,新垦红壤植稻后根际中活性Fe和Al富集;活性Mn量降低,但亏缺率小;活性Si则亏缺不明显,有时甚至富集。而熟化水稻土植稻后根际中活性Fe和Al则出现亏缺;Mn的亏缺较大,且差值明显;活性Si的亏缺现象更为显著。由于新垦红壤植稻后Fe和Al在根际微生态系统中富集,根茎叶中累积量较高,从而使Si、P和Mn等元素的吸收受阻,导致新垦红壤上水稻生长明显比熟化水稻土上的水稻要差。

Status of Si,Fe, Mn and Al in rhizosphere and its effect on rice (Oryza sativa L.) growth

The present research investigated the status of Si, Fe, Mn and Al in rhizosphere of two red earths and two paddy soils after planting rice and its effect on rice growth and element absorption with the combination of rhizobox and pot cultivation experiment. The results show that active Fe and Al are accumulated in the rhizosphere of red earths after rice planting, active Mn is less in the rhizosphere, while active Si is not conspicuous deficient and accumulated on occasion. In paddy soils, after growing rice, active Fe and Al in the rhizosphere has a definite depletion, active Mn has a high depletion, while active Si is depleted very obviously. These differences result in the decrease of element absorption, such as Si, Pand Mn during the rice growing period in two red earths. At the same time, Fe and Al are accumulated in both roots and shoots, and the element absorption and rice growth are hindered. All these findings should help to understand material cycling in rhizosphere microecosystem.