臺灣偽黑尾葉蟬及褐飛蝨之寄生天敵

Abstract

本項工作於1969~1970年間在稻田中進行，調查偽黑尾葉蟬（Nephotettix cincticeps (Uhler)）及褐飛蝨（Nilaporvata lugens (Stål））之部分寄生性天敵，結果如下：(一)偽黑尾葉蟬卵寄生蜂有6種：Paracentrobia andoi (Ishii), Oligosita sp. A, Oligosita sp. B, Lymaenon sp., Anagrus sp. 及Mymar? Indica Mani，在臺北稻田中之寄生蜂，以第1種佔最多，達70%，第3、4種較次，分別佔15、13％。在屏東稻田中之蟲口密度則以第2種為最多，佔77%。卵寄生蜂之寄生潛能在臺北似受環境因子所影響，在第1期水稻尚未收穫稻田具有覆蓋時，寄生率達24%，顯較水稻收穫後稻田空曠多日照之7，11%為高。可見卵寄生蜂發生雖普遍，其寄生潛能每受小氣候所限制而無法發揮。（二）褐飛蝨卵寄生蜂種類與偽黑尾葉蟬具有共通性，而以Anagrus sp.最多而普遍，在臺北稻田中其蟲口所佔比率達93％。各地之寄生情形，則每因寄主環境及發生季節而不同，最高寄生率可達80%，平均亦有62％。（三）偽黑尾葉蟬之寄生性頭虻發現有Tomosvaryella oryzaetora Koizumi, T. subvirescens (Loew), T. epichalca (perkins), T. sylvatica (Meigen), Pipunculus mutillatus Loew, P. javanensis de Meijere, P. orientalis (Koizumi)及P. roralis (Kertesz)8種，其中5種為寄主昆蟲祈紀錄（第2,3,4,5及8種），4種為臺灣分佈新紀錄（第l,9,4,7種）。在臺北稻田之發生密度以第1及第6種較多，分別佔43及31％。其寄生率之季節以8用份以前顯較其以徒為高，5月份時草地較稻田為高。在屏東稻田中成蟲之發生比率則以T. subvirescens佔70%。（四）各種天敵均經詳細記載形態特徵，附有分類檢索表及各種特徵照片以供鑑別。 The survey to the some parasites of the rice green leafhopper, Nephotettix cincticeps (Uhler) and brown planthooper Nilaparvata lugens (Ståi) was carried through 1969 to 1970 in the rice paddy cover the western coast of Taiwan including the areas of Taipei, Taichung, Changhwa, Yanlin, Chiayi and Pingtung. In this report, six species of egg-parasites (Trichogrammatidae and Myinaridae) and eight species of pipunculids were concerned. This paper included the studying methods, keys to species, collecting data, morphological descriptions and some biological notes. According to the collecting data, the parasi-tisms of Paracentrobia andoi (Ishii) (Trichogrammatidae) and Anagrits sp. (Mymaridae) were found more differently abundant on the parasitized-eggs of N. cincticeps and N. lugens than that of other species did (see table 2, 3). The percentages of parasitisms made by each species of egg parasites have been observed and detailly described in the paper and the tables. The parasite occurring was generally found little more frequent in the rice crowding area than that in the open area. The eight pipunculids of Tomosvaryella oryzactora Koizumi, T. subvirescens (Loew), T. epichalca (Perkins), T. ylvatica (Meigen), Pipunculus (Eudorylas) rnutillatus Loew, P. (E.) javanensis de Meijere, P. (E.) orientalis (Koizumi) and P. (E.) roralis (Kertesz) were systematically treated in this paper. Among the species, T. suhvirescens, T. epichalca, T. sylvatica, P. (E.) mutillatus and P. (E.) roralis were found associated withnew host in the world, also T. oryzaetora, T. subvirescens, T. sylvatica and P. (E.) orientalis were new in Taiwan again. By the investigation with the sweeping and rearing method, in Taipei area the parasitisms of T. oryzaetora and P. (E.) javanensis were relatively abundant than other speices (see table), hut in Pingtung area T. subvirescens was richer (see table 8) than other. Their seasonal occurring in general conclusion by the analysed field data was more common in the weedy land which near the rice paddy in the month of May.