Study on the Relationship between Root-rot Incidence and Soil-plant Nutrient Status for Aloe vera (L.) Burm. f.

The fertilization situation and root-rot incidence of Aloe vera(L.) Burm.f.were investigated in Yuanjiang County of Yunnan province,the samples of leaf and rhizosphere soil were collected and tested.The result showed that there was significantly positive correlation between root-rot incidence and available soil phosphorous,and no obvious correlation between root-rot incidence and other nutrients in soil and leaf.Moreover,the contents of alkaline N,organic matter,available K,available Ca,available Mg,available B in rhizosphere soil,and K and B in leaf were much lower,compared with healthy plants and their rhizosphere soil nutrition status in Hainan province,but the available phosphorous was much higher in rhizosphere soil in Yuanjiang.The possible reasons resulting in severe aloe root-rot in Yuanjiang might be nutrient disorder in soil and plant,disease multiplication and resistance reduction because of irrational fertilization,over-application of phosphorous and sugar refinery silt.