扶桑綿粉介殼蟲 Phenacoccus solenopsis (半翅目：粉介殼蟲科) 寄主偏好探討

Host preference of cotton mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae)

徐士恆(Shih-Heng Hsu)

指導教授 ： 蕭旭峰

國立臺灣大學/生物資源暨農學院/昆蟲學研究所/碩士(2020年)

https://doi.org/10.6342/NTU202003132

摘要

扶桑綿粉介殼蟲 (Phenacoccus solenopsis Tinsley) 源於美洲，現今於中國大陸、印度、台灣等亞洲地區皆有分布，為廣食性害蟲，具有極強的繁殖能力且擴張迅速，以刺吸式口器吸食植物的汁液，造成植物黃化、凋萎影響植物生長。本文先以大花咸豐草 (Bidens pilosa L. var. radiata Sch. Bip.)、南美蟛蜞菊 (Wedelia triloba L. Hitchc.)、馬纓丹 (Lantana camara L.) 三種常見的寄主植物，進行偏好性試驗，得知綿粉介殼蟲是否存在偏好性，及這三種常見植物中的偏好性高低。接著對於綿粉介殼蟲進行寄主經驗法則的試驗，前人研究顯示轉換不同寄主植物會影響綿粉介殼蟲的取食效率，但並未提及寄主經驗是否影響寄主選擇的偏好性，本試驗種植馬纓丹與大花咸豐草來進行選擇性試驗，藉由不同植物試驗以了解經驗法則是否影響寄主選擇。前面試驗結果顯示大花咸豐草有可能在田間作為中間寄主，透過選擇性試驗，了解大花咸豐草是否為綿粉介殼蟲在番茄 (Lycopersicon esculentum Mill., Solanaceae)、茄子(Solanum melongena L., Solanaceae)、朱槿 (Hibiscus rosa-sinensis L., Malvaceae)、南瓜 (Cucurbita moschata Duchesne ex Poir., Cucurbitaceae)、辣椒 (Capsicum annuum L., Solanaceae) 田間傳播的中間替代寄主。偏好性試驗中，綿粉介殼蟲在一齡若蟲與成蟲偏好性最偏高為大花咸豐草，二齡以及三齡若蟲則對三種植物無明顯偏好。寄主經驗法則試驗結果顯示寄主植物經驗不影響綿粉介殼蟲選擇的偏好性，無論是馬纓丹或是大花咸豐草。寄主轉移試驗中以大花咸豐草作為偏好的基準，各齡期綿粉介殼蟲對於番茄的偏好性低於大花咸豐草，對於南瓜的偏好性在二齡、三齡若蟲以及成蟲低於大花咸豐草，對於朱槿的偏好性，一齡以及二齡若蟲高於大花咸豐草，綿粉介殼蟲對於茄子、辣椒的偏好性與大花咸豐草無顯著差異。結果顯示大花咸豐草可作為中間寄主，廣泛地分布為扶桑綿粉介殼的擴散提供適合的條件。調查田間周遭大花咸豐草的有無可以作為扶桑綿粉介殼蟲傳染的初步判斷。Y型管嗅覺測試使用馬纓丹與朱槿作為氣味源，結果顯示綿粉介殼蟲對寄主氣味幾乎無反應，說明寄主氣味可能非綿粉介殼蟲搜尋寄主之主要依據。

關鍵字

扶桑綿粉介殼蟲 ； 寄主偏好 ； 寄主轉移

並列摘要

Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) was discovered in North America in 1898; so far, widely distributed in Asia and America, including Taiwan. Due to the polyphagous behavior of Phenacoccus solenopsis, it could quickly establish and expand its population in many plants. Plants that are harmed by Phenacoccus solenopsis may have symptoms such as leaf yellowing, withering, and poor fruit development. Firstly, we use three common weeds Bidens pilosa L., Lantana camara L. and Wedelia triloba L. to know if Phenacoccus solenopsis has different preferences for different plant species. According to the studies in bibliography, transfering Phenacoccus solenopsis onto different host plants will reduce its feeding efficiency, but no study mentioned about whether this will change its preference of the original breeding host plant. In this study, we use two plants, Bidens pilosa L. and Lantana camara L. to raise Phenacoccus solenopsis, and record whether they prefer the original host plant during the preference experiments. Furthermore, we chose the most common weed in Taiwan, Bidens pilosa L., to conduct the preference experiments to compare with various crop plants, including Lycopersicon esculentum Mill., Solanum melongena L., Hibiscus rosa-sinensis L., Cucurbita moschata Duchesne ex Poir. and Capsicum annuum L. The objective of this test is to know the possibility of Bidens pilosa to become an intermediate host or an overwintering host for cultivated crops, and providing the fundamental data to be used in the field prevention and control of Phenacoccus solenopsis. Finally, we use Y-tube to test how Phenacoccus solenopsis reacts to different plant volatiles. Results of the three weed preference experiments indicated that first instar nymphs and adults prefer Bidens pilosa. Second and third instar nymphs have no significant preference for all three plants. The experimental results of the host plants experience showed that the previous experience cannot change their preference either they were previously reared on Bidens pilosa or on Lantana camara. Host selection experiment comparing with Bidens pilosa showed that Bidens pilosa can attract Phenacoccus solenopsis at any instar on tomato leaves. On the contrary, the leaves of Hibiscus rosa-sinensis are attractive to the Phenacoccus solenopsis of any instar. Bidens pilosa can attract first and second instars and adult Phenacoccus solenopsis on Cucurbita moschata leaves. Comparing with the Bidens pilosa, Phenacoccus solenopsis have no preference for both Solanum melongena and Capsicum annuum. The results of the Y-tube test showed that Phenacoccus solenopsis did not respond to any plant volatile we offered. Our results support that the Bidens pilosa could be a possible intermediate host in the field, and their wide distribution may assist the mealybug dispersal. Field survey of the surrounding Bidens pilosa could be a useful preliminary index for monitoring the mealybug infestation.

並列關鍵字

Phenacoccus solenopsis ； host selection ； host shift

參考文獻

Abbas G, Arif MJ, Saeed S. 2005. Systematic status of a new species of the genus Phenacoccus Cockerell (Pseudococcidae), a serious pest of cotton, Gossypium hirsutum L., in Pakistan. Pak Entomol 27: 83-84.

Boufford ED, Hsieh CF, Huang TC, Kuoh CS, Ohashi H, Peng CI, Tsai JL, Cheng YK. 2003. Flora of Taiwan, Vol. 1. , 2nd ed. Editorial Committee, Dept. Bot., NTU, Taipei, Taiwan.

Chen HS, Huang LF, Jiang JJ, Zhou ZS, Wang WL, Meng X, Yang L. 2019. Host selection behavior of Phenacoccus solenopsis Tinsley and its correlation with the contents of biochemical substances in host leaves. Journal of Southern Agriculture 50: 768-774. (in Chinese).

Chen HY, Liu JX, Xu ZF. 2011. Description of a new platygastrid parasitoid Allotropa phenacocca (Hymenoptera) on Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae). Orient Insects 45: 275-280.

Chen MM. 2014. Life Table of Paracoccus marginatus on Four Host Plant Species in Taiwan [Master]. Taiwan: National Taiwan University. 64 pp. (in Chinese).