Does body size influence mating success? A morphometric study of two Anastrepha (Diptera: Tephritidae) fruit fly species

Comparison of Fecundity and Gall-Forming of the Horned-Gall Aphid, Schlechtendalia chinensis (Hemiptera: Aphididae) from Different Populations

The horned-gall aphid, Schlechtendalia chinensis, is the most economically valuable Chinese gallnut aphid species, playing a decisive role in the production of Chinese gallnuts. The method of cultivating the gallnut species with artificial moss and increasing the yield of gallnuts after inoculation has been applied in the main producing areas of Chinese gallnuts. However, it is still unclear whether artificial cultivation affects the fecundity and gall-forming effect of S. chinensis. In this study, autumn migrant aphids of S. chinensis from wild, artificial and introduced populations were used as materials to cultivate and inoculate under the same environment. The number of male and female sexuales, fundatrices, the galls per tree, and the total weight of galls per tree in subsequent generations were analyzed, and differences in the fecundity and gall-forming effects of different populations were analyzed. The results showed that the fecundity of the wild population was stronger than that of the artificial population, and the number of aphids produced by a single spring migrant and the number of fundatrices increased by 75.86% and 81.62%, respectively. Compared with the introduced population, the survival rate of female sexuales in the local population was higher. Compared with the artificial population, the gall-forming effect of the wild population was better; the number of galls per tree, the weight of single gall, and the total weight of galls per tree increased by 68.33%, 50.77%, and 153.78%, respectively; and the gall preservation rate increased significantly. Artificial cultivation of S. chinensis will lead to a decrease in fecundity and gall-forming effect in subsequent generations, showing the degradation of the vitality of S. chinensis. Therefore, it is necessary to improve the effect of artificial cultivation of S. chinensis by adopting technical measures such as wild population or introduction.

Effects of adult-diet modifications on sexual maturation rate, body weight, and quantity of sperm transfer by male Mexican fruit fly (Diptera: Tephritidae)

Mass-reared sterile Mexican fruit flies (Anastrepha ludens [Loew]) are released along the US-Mexico border to control fruit fly damage and spread. It is more cost effective for the mass rearing program if males mature at a younger age because they can be held for a shorter time at the facility before release. In this study, adult male Mexican fruit fly diets were tested to determine if the current diet used at the mass rearing facility promotes younger mating and optimal sperm transfer compared to other diet formulations. Hydrolyzed yeast presentation methods were examined: an agar-free dry mixture of yeast and sugar (Y+S), yeast embedded in the diet during the agar boiling process (current method used) and sifted dry on the ager gel surface. Methoprene, a juvenile hormone analog was also tested as a supplement to agar gel diets with and without yeast. A greater proportion of males fed Y+S mated 1 day earlier than males fed other diets. Male mating age and diet did not significantly affect the quantity of sperm transferred; however, a non-significantly higher percentage of males fed diets with embedded yeast transferred enough sperm to fill all 3 spermathecae. The results suggest that the current diet used is optimal for mass-rearing the flies and that yeast presentation method has a significant effect on A. ludens male mating age but not on the quantity of sperm transferred to females.