甘肃省秦安县苹果叶缘焦枯死亡原因的初步研究

Preliminary Survey on the Cause of Withered and Die off of Apple Leaf in Qin`an County of Gansu

针对甘肃秦安县苹果叶缘焦枯发生严重的情况,对该地果园叶片和土壤进行了分析。结果表明,正常果园叶片全钾含量平均值为9.2 g/kg,叶片钠含量平均值为315 m g/kg,K+/N a+为29.2;而发病果园叶片全钾含量平均值为4.2 g/kg,叶片钠含量平均值为3 900 m g/kg,K+/N a+为1.1,与正常果园K+/N a+相比,相差26.5倍。正常果园土壤pH值为8.2,发病果园土壤pH值为8.6,相差0.4个单位;发病果园要比正常果园土壤水溶性N a+高84.9 m g/kg,初步认为秦安县苹果叶缘焦枯死亡的原因是由于土壤中钠盐含量过高所致。

The apple leaf and soil in orchard of Qinran county of Gansu were investigated. The results indicated that total potassium content of leaf was 9.2 g/kg, sodium content of leaf was 315 mg/kg in health orchard, K^＋/Na^＋ ratio was 29. 2. But total potassium of leaf was 4. 2 g/kg, and sodium content of leaf was 3 900 mg/kg in leaf marginal withered orchard, K^＋/Na^＋ ratio was 1.1, it was less 26.5 times than the health orchard. Soil pH was 8.2 in health orchard, it was less 0.4 units than the leaf marginal withered orchard. And the water-soluble sodium in health orchard was less 84.9 mg/kg than that in leaf marginal withered orchard. In conclusion, the reason of apple leaf withered away could be deduce excessive sodium content in the soil of leaf withered orchard.