柑橘黄龙病对沙田柚树体特性和果实品质的影响

Effects of Citrus Huanglongbing on Tree Traits and Fruit Quality of Citrus maxima(Burm.)Merr.cv.Shatian Yu

柑橘黄龙病(Citrus Huanglongbing,简称HLB)是柑橘的毁灭性病害,柑橘感染后不仅导致叶片黄化,影响果实品质,而且会使树势减弱直至植株死亡。本研究以感染黄龙病和健康沙田柚[Citrus maxima(Burm.)Merr.cv.Shatian Yu]为材料,对比分析黄龙病树(HLB+)和健康树(HLB-)在叶片形态特征、果实品质、矿质元素等方面的差异,旨在掌握黄龙病对沙田柚树体和果实的影响,为促进柑橘黄龙病的防控提供理论参考。沙田柚黄龙病植株与健康植株相比,叶片面积减少28.13%,叶绿素a、叶绿素b和类胡萝卜素分别降低40.38%、44.00%和40.47%;果实外观着色异常且果实偏小,平均单果重下降45.62%,果皮变薄,种子败育增多,果实维生素C升高26.44%,达到显著水平,并且不同组织的多个元素发生显著变化。与健康植株相比,黄龙病叶片N和Ca元素分别减少19.00%和49.72%,果肉N元素减少18.00%,而果皮和果肉Ca元素显著升高;病树根、叶片、果皮和果肉S元素均显著低于健康树。病树叶片B和Cu元素分别降低了35.07%和54.45%,果皮Cu元素显著降低了42.96%,果肉Zn元素显著升高了41.30%。黄龙病严重影响了沙田柚叶片形态和果实品质以及矿质元素代谢,应高度重视提高沙田柚果园的黄龙病防控管理水平。

Citrus Huanglongbing(HLB)is a devastating disease that seriously affects the development of citrus industry.It not only leads to leaf yellowing and affects the fruits quality,but also affects the life cycle of citrus trees.In order to investigate the effects of HLB on Shatian pomelo[Citrus maxima(Burm.)Merr.cv.Shatian Yu],the effects of HLB on the leaf morphological characteristics and fruit appearance and internal quality as well as mineral elements of Shatian pomelo were systematically analyzed.The result could provide references for the control of citrus HLB.In this study,the HLB positive Shatian pomelo trees and fruits were used for the experimental group(HLB+)and the HLB negative Shatian pomelo trees and fruits were used as the control group(HLB-).The leaf area,content of chlorophyll a,chlorophyll b and carotenoid of HLB+leaf decreased by 28.13%,40.38%,44.00%and 40.47%,respectively.The color of the HLB+fruits was abnormal and the fruits of HLB+was smaller.The average fruit weight of HLB+fruits decreased by 45.62%.The HLB+fruits had thinner peels and its most seeds could not develop normally.The vitamin C content of HLB+fruits was significantly higher than that of HLB-fruits,increased by 26.44%.The content of mineral elements in different tissues changed obviously after infection with HLB.The content of N and Ca of the leaves decreased by 19.00%and 49.72%,respectively,and the content of N of the pulp decreased by 18.00%,but the content of Ca of HLB+peel and pulp significantly increased compared to the HLB-peel and pulp.And the content of S of the HLB+trees was significantly lower than that of the healthy trees.The content of B and Cu of the HLB+leaf decreased by 35.07%and 54.45%,respectively.The content of Cu of the HLB+peel decreased by 42.96%and the content of Zn of the HLB+pulp increased by 41.30%.HLB seriously affected the leaf morphology,fruit quality and mineral element metabolism of Shatian pomelo trees.So more attention should be paid to the prevention and control of HLB-infected Shatian pomelo.