茶實象鼻蟲生活史調查報告

Report on a Survey of the Life of Balaninus Camelliae Roelofs

林寶琛(P.C. Lin) ； 黃梅頌(M.S. Huang)

《中華農業研究》 7卷3期 (1957/12) Pp. 26-36

https://doi.org/10.29951/JARC.195712.0003

摘要

(l)茶實象鼻蟲分類地位
(A)鞘翅目　(B)象鼻蟲亞目
(C)象鼻蟲科　(D)真象鼻蟲亞科
(E)實象蟲屬　(F)茶實象鼻蟲
(2)分佈：此蟲早於民國二十六年日人楚南氏在嘉義阿里山的奮起湖附近及南投縣魚池鄉本分所茶園發現，富初發生極少爲害茶寞輕微，直至民國四十二年至今在本分所茶園大量發生爲害，臺灣其他茶區尚未發現。
(3)雌雄成蟲形熊上之差異：雌雄成蟲在外形上之主要區別，係雌蟲嘴長平均5.89公釐，而雄蟲平均謹4.33公釐，雌雄蟲最明顯之區別是雌蟲嘴前段均較觸角前段爲長，平均焉+0.84公釐，雄蟲則嘴前段反較觸角前段爲短，平均焉-0.47公釐，其他各部份雌雄無大差別，雖雌蟲身軀較大，但以肉眼甚難察覺。
(4)成蟲之習性：成蟲生性活潑，每次飛翔遠達七至八公尺，具有三對強健粗壯之爬行足，行勤迅速，並有墜落性與僞死性，成蟲之食性輿幼蟲不同，成蟲以未成熟之果實液爲其覓食之封象，日間交尾，雌蟲産卵於其嚙食果仁中之圓錐形墜道中，普通一穴中僅産卵一粒。
(5)卵之形熊：卵爲長圓錐形，長約0.8公厘，濶豹0.2公釐，全體白色，表面光滑。
(6)幼蟲之習性與天敵：幼蟲自卵孵出俊，郎在此果實中度過其整個幼蟲期，僅以種仁爲食。其齡期在三齡以上。幼蟲身軀肥大成乳黃白色，直經約5公厘，無足，竟能蠕動行走每次可達2.5公尺。幼蟲老熟俊，自果實啃出隧落地面俊，隨卽鑽入土中，以唾液粘土粒做成土繭，並於土繭中休眠越冬，土繭離地面20到30公分處。
自種籽中剝出之死亡幼蟲身軀上，發現一種寄生蜂之幼蟲，學名不詳，但發現次數不多，是否爲錯誤寄生，尚未獲悉，又另自死亡幼蟲之屍體上發現一些菌類，未見有何種寄生昆蟲發生，其幼蟲之死亡可能爲某種菌類侵害，但目前還未作淮一步之研究。
(7)蛹之形熊與蛹期：幼蟲經過長久之休眠越冬俊始變爲蛹，蛹爲裸蛹平均是達0.926公厘，濶達0.524公厘(最濶點)蛹期長約十至十八天，全部蛹期在茶園土壤中度過，自土中掘出之初蛹，其體色與幼蟲相同，蛹體甚活潑，如外物觸其蛹體則搖擺不休。
(8)生活史：成蟲期五月上旬至九月底，五月下旬至十月上旬發現卵，六月上旬幼蟲出現以至十月中旬。其後經過一極長之休眠期，蛹期約十八天。
(9)一年中發生之代數：茶實象鼻蟲一年僅發生一代，並與茶籽生長成熟同一時期。

並列摘要

This weevil was first discored by a Japanese called Sonan in 1937, in the neighbour-hood of Feng-Chi Lake, Chiayi-Hsien, and in the tea gardens of this Experimental Station Yu-Chih Hsiang, Nantou Hsien. When discovered, these weevils were few and caused only a slight harm, but from 1953 upto now they multiplied rapidly to such an extent as to make their harm quite felt in the tea gardens of this Experimental Station and so far no presence of them was noticed in the other tea plantations of this Island.
The adults are very active and can fly as far as 7 to 8 meters. They, equipped with three pairs of strong climbers, move very quickly, and are apt to fall down from their perch when rocking the tea bush and sometimes pretend to die when falling on their back on the ground. The adults eat their way into the transparent paste-like kernel of the unripe tea seeds until they lay their eggs in there, an egg a time sometimes two or three but rarely, such eggs are cylindrical in shape and 0.8 mm. long and 0.2 mm. wide, white in colour with smooth surface.
Its larvae feeding on the kernel spend their whole formative stage in the seeds for about five to six months, such larvae, creamy colour, and about the size of 5 mm., have no feet and can only crawl about, sometimes as far as 2.5 meters. They, when developed, eat their way out of the seeds and fall to the ground. And immediately wriggle down into the earth and spend the whole winter in a stage hibernation about 20-30 CM. below the surface of the earth.
Such larvae after a long period of hibernation in the earth, become pupas in middle- April to early May, which are about 0.926 mm. long and 0.524 mm. wide (the widest part) pupation generally lasts 10 or 18 days, all this time spent under the soil of the tea gardens. Such pupas, dug out of the soil for observation, are quite identical with the larvae in body colour, but are very sensitively active, and vibrate consider only when touched on leg anything else. These pupas develop into adults in early May, and lay eggs in late May, which hatch into larvae in early June.
These weevils cause a great amount to the tea seeds, though they propagate only one generation a year. With financial assistance of JCRR. We are now planning to study on how to control their propagation in the tea gardens as well as to exterminate them once and for all.