FACTORS AFFECTING THE INTERSPECIFIC MATING BETWEEN NEZARA VIRIDULA L. AND N. ANTENNATA SCOTT AND ITS EFFECT ON THE REPRODUCTION

• Published in: JAPANESE JOURNAL OF ECOLOGY Vol. 15; no. 4; pp. 148 - 151
• Main Authors: HOKYO, Nobuhiko, KIRITANI, Keizi
• Format: Journal Article
• Language: Japanese
• Published: The Ecological Society of Japan 01.08.1965
• ISSN: 0021-5007; 2424-127X
• DOI: 10.18960/seitai.15.4_148

A field cage experiment using the two closely related stink bugs, Nezara viridula L. and N. antennata Scott, was made to study the significance of interspecific mating between those species. Intraspecific mating of viridula considerably preceded that of antennata, and the latter occurred a few days later than the interspecific mating, viridula female×antennata male. The reciprocal combination of interspecific mating was not observed during the present experiment. These facts indicated that the interspecific mating was partly caused by the difference in sexual maturation between the species and between the sexes of antennata. The sex ratio (♀/♂+♀) of viridula in the late period of the experiment became high due to the differential mortality between the sexes. The shortage of males in relation to the number of viridula females forced the latter to mate with antennata males. And a few females of viridula oviposited some unfertilized eggs due to the interspecific mating. In fact, however, all females of viridula had a chance of intraspecific mating at least once before the interspecific mating. Therfore, in nature, the ill effect of interspecific mating becomes decisive only when the relative abundance of the one species persistently predominates over that of the other.