Abstract: Using Aphis craccivora K. as the diet, the effects of different female-male ratios on the laying capacity and hatchability of Coccinella septempunctata under the same feeding density were studied. And using the ratio of 3∶1 as the preferred female-male ratio, the effect of raising Coccinella septempunctata of different densities in a 1 000 mL container on its spawning volume and hatchability was studied. The results showed that spawning volume by Coccinella septempunctata was significantly higher when the female-male ratios were 1∶1, 2∶1 and 3∶1 than those of 4∶1 and 5∶1. With a female-male ratio of 3∶1, the spawning volume of 9 females and 3 males in a container of 1 000 mL was significantly higher than that of 3 females and 1 male, 6 females and 2 males, 12 females and 4 males, 15 females and 5 males. The female-male ratios and the feeding density had no significant effect on hatchability.

Key words: Coccinella septempunctata L., artificial breeding, female-male ratio, feeding density, spawning volume, hatchability