21521143
not annotated - annotated - LINNAEUS only
Post-egression host tissue feeding is another strategy of host regulation by the Koinobiont wasp, Toxoneuron nigriceps.
Koinobiont wasps start their lives as hemolymph feeders inside the host body, but before they egress from the host many become tissue predators. One species, the endoparasitoid Toxoneuron nigriceps Viereck (Hymenoptera: Braconidae), exhibits the unusual behavior of egressing before initiating tissue predation. After egression from the host, it reinserts its head into the host body to begin tissue feeding. These third instar T. nigriceps larvae show a significant increase in body size and mass after post-egression feeding. Through this project the importance of post-egression feeding in the development of T. nigriceps in its host the tobacco budworm, Heliothis virescens Fabricius (Lepidoptera: Noctuidae), has been evaluated. The study was conducted by preventing the egressed third instar T. nigriceps larvae from feeding on host tissue and observing whether they could undergo further development. Though some of the larvae that were prevented from post-egression feeding did undergo cocoon formation, pupation, and adult emergence they were inferior in terms of size, body mass, and survival to those that developed from larvae allowed to feeding after egression. Hence, it is concluded that post-egression host tissue feeding is essential for the normal development of T. nigriceps, as the prevention of feeding resulted in significantly lighter and smaller larvae, cocoons, and adults as well as deformed adults and reduced adult survival. Post-egression feeding as a host regulatory strategy is discussed.
Ann file
T1 Species 98 118 Toxoneuron nigriceps
N1 Reference T1 Taxonomy:51531
T2 Species 299 319 Toxoneuron nigriceps
N2 Reference T2 Taxonomy:51531
T3 Species 550 562 T. nigriceps
N3 Reference T3 Taxonomy:51531
T4 Species 734 746 T. nigriceps
N4 Reference T4 Taxonomy:51531
T5 Species 763 778 tobacco budworm
N5 Reference T5 Taxonomy:7102
T6 Species 780 799 Heliothis virescens
N6 Reference T6 Taxonomy:7102
T7 Species 920 932 T. nigriceps
N7 Reference T7 Taxonomy:51531
T8 Species 1403 1415 T. nigriceps
N8 Reference T8 Taxonomy:51531