昆虫学报 ›› 2020, Vol. 63 ›› Issue (2): 166-173.doi: 10.16380/j.kcxb.2020.02.006

• 研究论文 • 上一篇    下一篇

亚洲柑橘木虱成虫和5龄若虫在感染黄龙病的柑橘上的取食行为及获菌效率比较

乌天宇1,2, 张旭颖1, George A. C. BEATTIE3, 岑伊静1,*   

  1. (1. 华南农业大学昆虫生态研究室/华南农业大学柑橘黄龙病研究室, 广州 510642; 2. 南方日报, 广州 510000;3. School of Science and Health, Western Sydney University, Penrith, NSW 2751, Australia)
  • 出版日期:2020-02-20 发布日期:2020-02-25

Comparison of feeding behaviors and pathogen acquisition rates of adults and the 5th instar nymphs of Diaphorina citri (Hemiptera: Liviidae) on huanglongbing-infected citrus plants

WU Tian-Yu1,2, ZHANG Xu-Ying1, George A. C. BEATTIE3, CEN Yi-Jing1,*   

  1.  (1. Laboratory of Insect Ecology/Citrus Huanglongbing Research Laboratory, South China Agricultural University, Guangzhou 510642, China; 2. Nanfang Daily, Guangzhou, 510000, China; 3. School of Science, Western Sydney University, Penrith, NSW 2751, Australia)
  • Online:2020-02-20 Published:2020-02-25

摘要: 【目的】亚洲柑橘木虱Diaphorina citri是柑橘的毁灭性病害——黄龙病亚洲种‘Candidatus Liberibacter asiaticus’(‘Clas’)的主要传播媒介。本研究的目的是明确木虱成虫和5龄若虫的取食行为、获菌效率是否有差异,以及寄主感染黄龙病是否对5龄若虫取食产生影响。【方法】利用直流型刺吸电位仪(DC-EPG Giga-4)记录柑橘木虱成虫和5龄若虫在携带黄龙病的酸橘Citrus reticulata cv. Sunki嫩梢上10 h的取食行为,用qPCR单头检测其获得黄龙病病原菌的效率,并比较5龄若虫在感病和健康植株嫩梢上的取食行为。【结果】柑橘木虱成虫与5龄若虫在感染黄龙病的酸橘上的取食行为有显著差异。5龄若虫比成虫更快地开始在韧皮部和木质部进行吸食,口针在韧皮部的总过程以及吸食时间显著长于成虫。此外,5龄若虫和成虫在EPG测定(同时饲菌)10 h后获菌率分别为37.5%和20.0%,若虫明显高于成虫。寄主植物感染黄龙病对5龄若虫的取食行为有一定的影响,表现在感病植株上的刺探次数、唾液分泌次数和韧皮部吸食次数都显著少于健康植株,而两者分泌唾液和韧皮部吸食时间没有显著差异。另外,在感病植株上首次韧皮部取食出现时间较在健康植株上要早。【结论】在同等时间下,柑橘木虱5龄若虫比成虫在感染黄龙病的酸橘上的取食能力更强、取食量更大、获菌率更高,原因可能是若虫需要更多的营养物质供其生长发育所致。寄主感染黄龙病对木虱5龄若虫的取食有利,使其更快地开始取食,而且更改取食位点次数变少,推测可能与黄龙病菌破坏了植物的防御有关。

关键词: 亚洲柑橘木虱, 柑橘, 黄龙病, 取食行为, 获菌效率, 刺吸电位

Abstract: 【Aim】 The Asiatic citrus psyllid (ACP), Diaphorina citri, is the major vector of ‘Candidatus Liberibacter asiaticus’ (‘CLas’) (α-Proteobacteria), the pathogen that causes the Asiatic form of huanglongbing (HLB), the most devastating disease of citrus. The aims of this study are to determine whether the feeding behaviors of adults and the 5th instar nymphs of D. citri differ, and if so, whether these differences influence pathogen acquisition efficiency, and whether HLB-infected plants influence feeding by the 5th instar nymphs. 【Methods】 The feeding behavior of adults and the 5th instar nymphs of D. citri on immature shoots of HLB-infected Citrus reticulata cv. Sunki was recorded for 10 h with DC-EPG giga-4. The acquisition efficiency of the pathogen by individual adults and nymphs from HLB-infected shoots was determined by qPCR. The feeding behaviors of the 5th instar nymphs on pathogen-free and HLB-infected shoots were also recorded and compared by EPG. 【Results】 The feeding behaviors of adults and the 5th instar nymphs of D. citri on C. reticulata cv. Sunki shoots infected with HLB differed significantly. The 5th instar nymphs started to ingest xylem and phloem sap sooner than adults. Durations of the phloem salivation and ingestion phases of nymphs were significantly longer than those of adults. When feeding on HLB-infected shoots, 37.5% of the 5th instar nymphs acquired ‘CLas’ in contrast 20% of adults. The frequencies of probing and salivation and phloem sap ingestion by the 5th instar nymphs feeding on HLB-infected shoots were significantly lower than those on healthy shoots. However, HLB-infected plants did not influence the duration of phloem salivation and sap ingestion by the 5th instar nymphs. Feeding also commenced sooner in phloem of HLB-infected shoots than in phloem of healthy shoots. 【Conclusion】 The 5th instar nymphs of D. citri feed for longer intervals, ingest more phloem sap, and acquire higher titers of ‘CLas’ than adults. This may be due to that nymphs require more nutrients for their growth and development than adults. They are therefore less inclined to withdraw their stylets from, and re-insert their stylets into ‘CLas’-infected leaf tissues. ‘CLas’-induced changes in host-plant phytochemistry promote feeding by the 5th instar nymphs of D. citri.

Key words: Diaphorina citri; Citrus reticulata, huanglongbing, feeding behavior, pathogen acquisition efficiency, electrical penetration graph