Studies on the Biological Control of the Diamondback Moth, Plutella xylostella (Linnaeus) : 2. Effect of Temperature on the Development of the Egg-Parasitoids, Trichogramma chilonis and Trichogramma ostriniae

The effect of temperature on the development of two egg parasitoids, Trichogramma chilonis and T. ostriniae, which attack the diamondback moth, were observed in the laboratory under the controlled conditions of constant temperatures (16℃, 20℃, 24℃, 28℃ and 32℃). The results are summarized as follows: 1. The developmental periods from the egg to the adult emergence of two parasitoids became shortend as temperature became higher. 2. The developmental zero of T. chilonis and T. ostriniae were 11.1℃ and 11.7℃, respectively. The effect heat units required from the egg to the emergence of adult of T. chilonis and T. ostriniae were 121.2 day-degree and 134.7 day-degree, respectively 3. The percentage of emergence of two parasitoids developed on the egg of Ephestia kuehniella were higher than those on the egg of Plutella xylostella.2種のタマゴヤドリコバチ,Trichogramma chilonisとT.ostriniaeの発育と温度の関係を調査した.結果を要約すると以下の通りである.1.両寄生蜂の卵から成虫羽化までに要する発育所要日数は,温度の上昇とともに短くなった.2.スジコナマダラメイガ卵で発育するとき,T.chilomsの発育零点は11.1℃,T.ostriniaeは11.7℃であった.また,T.chilonisの卵から成虫羽化までに要する有効積算温度は121.2日度,T.ostriniaeは134.7日度であった.3.両寄生蜂の羽化率は,スジコナマダラメイガ卵で発育するときが,コナガ卵で発育するとさよりも一般的に高かった