土壤因子对库尔勒香梨缺铁失绿症发生的影响

Effects of Soil Factors on Iron-deficit Chlorosis of Kuerle Fragrant Pear(Pyrus Bretschneideri Rehd)

对香梨产区10个点的土壤样品进行理化特性分析,结合黄化病田间调查资料,研究土壤因子对库尔勒香梨缺铁失绿症发生的影响。结果表明,香梨在南疆钙质土壤上叶片失绿黄化是多种土壤因子交互作用的结果。土壤高pH(平均为8.49)和有效铁含量低(平均为12.2mg/kg)是诱发香梨叶片缺铁失绿的两大因素。上层土壤中浓度高达7mmol/L HCO3-对土壤铁的活化与运输有着潜在的影响。土壤中较低的有效铁含量可能与较高的锰、锌、铜含量之间的生理拮抗关系也是导致香梨黄化失绿的原因之一。水溶性钙在土壤表层有累积现象。

In South Xinjiang calcareous soil,serious iron-deficiency chlorosis frequently occurred in Kuerle Fragrant Pear.The characteristics of soil from 10 sites were investigated to study the effects of soil factors on the iron deficiency chlorosis.The results indicated that the leaf chlorosis of Fragrant Pear in calcareous soils resulted from interaction of several soil factors such as higher pH,limited available Fe concentration,higher HCO3-and so on.The higher pH（average 8.49） and lower available Fe（average 12.2 mg/kg） were main factors inducing chlorosis.It was the higher HCO3-concentration by 7 mmol/L that potentially affected on the activation and mobilization of iron of the upper layer soil.The antagonistic relationship between available Fe and higher available Mn,Zn and Cu also probably increased iron deficiency chlorosis.The water soluble calcium accumulated in the upper layer soil.