Pembentukan Kapsul/Nodul Larva Helicoverpa armigera Hubner (Lepidoptera: Noctuidae) Pasca Infeksi HaNPV (Helicoverpa armigera NUCLEAR POLYHEDROSIS VIRUS)
Abstract: NPV is one of the
biological insecticides that kills the target by infecting their cells
including hemocytes. Hemocytes play a key role on defence mechanism against
pathogens like NPV. This defense mechanism may cause the insect to become more
tolerant as well as to chemical insectisides. The tolerances of insect to NPV
could be induced by cellular immune system (CIS). One of the CIS is
capsules/nodules formation. Based on that assumption, this research was
conducted to observe the alteration of capsules/nodules formation of
Helicoverpa armigera larvae post sublethal infection of HaNPV (Helicoverpa
armigera nuclear polyhedrosis viruses). The fifth instar Helicoverpa armigera
ware infected by sublethal doses of HaNPV. 24 hour post infection, partly of
survive larvae reared to get their first (NPV-F1) and second filial (NPV-F2).
Another survivor induced by hit killed Bacillus cereus, and then its haemocoel
were exposed under stereo microscope (total magnification, 60 X) to watch
capsules/nodules that appear as black spots on haemolymph. This procedure also
conducted to fifth instar larvae of NPV-F1, NPV-F2, control (K-P) and their
filial (K-F1 and K-F2), blank and placebo. The result showed that the number of
nodules/capsules on larvae were not significant between control and the
NPV-treat larvae on every generation, which was about 4 nodules/capsules. It
showed that there is no cellular immune respon changed on NPV-P larvae, so
their immune ability are similar to larvae K-P. The recoveries of NPV-P larvae
cause it have a good capability to produce offspring with good immune response.
So, NPV-F1 and NPV-F2 larvae have same ability as K-F1 and K-F2 larvae. It can
be concluded that the use of sublethal dosage of HaNPV has not changed
formation of capsules/nodules of H. armigera larvae and their offspring.
Penulis: Kurnia Nani
Kode Jurnal: jpbiologidd100181
