库尔勒香梨黄化病年度发生规律调查

Investigation on Annual Occurrence Law of Yellows Disease of Kuerle Fragrant Pear

【目的】对库尔勒香梨黄化病年度发生规律进行了调查，旨在为香梨缺铁诊断和防治提供参考。【方法】以黄化株为试材，与正常株为对照，对新梢长度、叶面积、叶片叶绿素含量、果实品质进行了测定，并对叶片结构进行了解剖学研究。【结果】黄化株新梢长度、叶面积、叶片厚度、叶绿素含量均显著低于正常株；黄化株果实硬度、酸度增大，单果重、可溶性固形物较正常株显著减小；解剖研究表明黄化株的叶片栅栏组织和海绵组织厚度、栅栏组织与海绵组织的比值均明显下降。黄化株在整个生长季均有明显症状，其中5月底-6月初病情表现最为典型。【结论】黄化病造成香梨叶片光合代谢失调，营养生长迟缓，生殖生长受限，严重威胁着香梨商业化栽培。对黄化病诱发原因进行深人分析，并采取有效的防治措施是香梨生产亟待解决的一个实际问题。

[ Objective]The present study investigated the annual occurrence law of yellows of Kuerle Fragrant Pear to provide the related basis for discussing its occurrence mechanism. [ Method ] The length of different tree shoot, leaf area, weight per leaf, leaf chlorophyll content and fruit quality of Kuerle Fragrant Pear were tested by use of yellows tree of Kuerle Fragrant Pear and normal tree as research materials. [ Result ] The results showed that ehloritic tree＇s shoot length, a leaf area, a leaf weight and chlorophyll a ＋ b content all are lower than those of normal trees, and their peak appeared at the end of June. Chloritic tree＇ s fruit external quality is lower than that of normal tree, but in internal quality, chloritic tree＇s acidity is higher than that of normal tree, soluble solid content is lower than that of normal tree, soluble sugar and vitaminc have not signigicant difference from that of normal tree （ P 〉 0.05 ） . [ Conclusion] The occurrence of chloritic appearance of Kuerle Fragrant Pear is caused by yellows disease which brings about chloritic trees grow slowly, leaves become yellow, chlorophyll a ＋ b contents and yield both decline, and this disease severely threaten fruit tree＇ s yield. Therefore, it is of great importance that the effective measures should be adopted to control the occurrence of the yellows disease of Kuerle Fragrant Pear.