苗代期のニカメイガ卵塊の分布, および卵寄生バチの寄生状態

概要

論文の詳細を見る
1) In 1955 and 1956m, investigations were carried out on the first brood of emergency of the rice stem borer, Chilo suppressalis WALKER, and its egg parasites, Trichogramma japonicum ASHMRAD and Phanurus beneficiens ZEHNTER, in rice nurseries at several places in Matsue City. 2) The number of egg masses deposited by the moth was daily recorded in a rice nursery at Nogi, Matsue City, and it was found that the distribution of egg masses in that nursery was heterogeneous. 3) The densities of the egg masses were almost similar, in a relatively limited region, excepting a few nurseries of high densities. There was no tendency that the size of egg mass, i.e. the total number of eggs composing an egg mass, was significantly large in such a nursery of high densities as mentioned above. 4) The local distribution of egg masses was investigated at Ikuma, Matsue City, in 1956. This district is flat and is uniform in the rice cultivation, but the density of egg mass in a rice nursery was significantly lower at a certain region than of other parts of the district. 5) There was a tendency that the percentage of parasitism of egg masses was low in the rice nursery of high density of host egg. This phenomenon seems to be explainable assuming that the number of adult parasites is nearly constant regardless of the host density in a rice nursery.
日本生態学会の論文
1956-12-31