|Title:||嘉南地區瘤野螟之生態觀察||Other Titles:||Investigation on Biononiics of the Rice Leaffolder, Cnaphalocrocis medinalis (Guenee) In the South of Taiwan||Authors:||鄭清煥
|Keywords:||瘤野螟;生活史;取食葉面積;族群及被害葉消長;Rice leaffolder;Bionomics;Damage||Issue Date:||Jun-1987||Publisher:||植病保護學會||Journal Volume:||29||Journal Issue:||2||Start page/Pages:||135-146||Source:||植物保護學會會刊||Abstract:||
瘤野螟原為本省偶發性水稻害蟲，近年來常於二期作造成嚴重危害。本蟲係以其幼蟲捲起稻葉並藏匿於捲葉中取食葉片組織，而嚴重影響水稻之光合作用。每隻幼蟲平均可捲稻葉3至5片，隨稻株之生育期而增加，取食葉片面積則隨葉片之老化而減少。以同齡期葉片餵食，其取食葉面積由19.8 cm2至34.0 cm2，其中第五齡蟲之取食面積約佔全幼蟲取食面積之50-74%隨溫度而異。瘤野螟之卵、幼蟲及蛹之發育臨界分別為12.3、11.1及13.9℃，有效積溫分別為60.2、240.8及88.3日度。成蟲壽命隨溫度升高而縮短，但其產卵量則反之，在30℃每雌蟲平均可產卵260粒。在室溫下採田間各生育期水柄葉片連續飼養，本蟲一年可完成10世代，各世代幼蟲發育所需時閒顯受溫度及稻葉品質所左右，以水稻成熟期葉片飼養，幼蟲期顯著地延長，且有3-6%之個體可增加脫皮一次發育至6齡蟲。田間調查發現本蟲在嘉南地區一年可完成九世代，在第一及第二期作每期可遭受三個世代危害，其成蟲高峰分別出現於6月中旬及10月中、下旬。吸式誘蟲燈及雌女誘蟲器均可充分反應本蟲在田間之族群密度。依據本蟲幼蟲密度及被害葉率之進展，發現在第一期作並無防治需要，而二期作則應以第七世代幼蟲期（出現於10月上旬）為防治之重要時期，其防治基準建議定為每叢稻有幼蟲1隻或被害葉3片。
The rice leaffolder, Cnaphalocrocis medinalis being a sporadic insect pest of rice in Taiwan, has become increasingly abundant in recent years. The damage caused by this pest to rice plant is mainly by the larva which feeds on the green chlorophyll protion of the leaf, leaving only the underside epidermal membrane along the vein of the leaf. The total rice leaf area consumed per larva during its whole growing period was from 19.3 to 34.7 cm2 and about 50 to 74% of which being caused by the last instar larva. The larva, however usually attacked 3 to 5. leaves before pupation. The threshold temperature for development of egg, larva and pupa were estimated to be
12.3, 11.1 and 13.9℃, and the thermal constants for each above mentioned stage were 60.2, 249.8 and 88.3 day-degrees, respectively. Life span of adult was about 12 days at 30℃ and increased to more than 27 days at 15℃. The average number of egg-laid per female was about 260 at 30℃, 160 at 20℃ and no egg laid at 15℃. The insect could completed 10 generations a year under room temperatures, however, only 9 generations could be traced out basing on the data collected by using three different traps and field investigations. The duration for larvae each generation were affected distinctly by both temperature and food quality, the leaves from ripenning plant stage prolonged the larval period and induced about 3 to 6% larvae developing to 6th instar. Suction light trap and virgin female trap showed more efficiency for monitoring the adult population than the other. Adult population peaks in the first and second rice crop appeared separately in the middle. June and from the middle to the end of October From the population development and infestation of the pest, it is suggested that no control is needed in the first rice crop, while the larval stage of the 7th generation, which appeared usually during the first decade of October, is a suitable time for control of the pest in this area.
|Appears in Collections:||植物保護系|
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