Published online by Cambridge University Press: 19 September 2011
A bioassay was developed to assess the in vitro feeding responses of Chilo partellus larvae to susceptible (Inbred A) and resistant (MP 704) maize varieties. Consumption of internode tissues from the two maize varieties differed while the reverse was true for the nodes. Aqueous extracts from the two varieties caused a decrease in feeding and weight gain, but these effects were more evident in MP 704 than in Inbred A treatments. This suggests that MP 704 has a water extractable factor affecting weight gain negatively. Dose-response curves of neural responses from the maxillary styloconica sensilla showed that aqueous extracts from the two maize varieties evoked different functional forms of impulse frequencies especially in the lateral sensilla. These observations suggest that the quality of gustatory stimuli in the two maize varieties differs.
Un test in vitro fut develope pour examiner le comportement nutritionnel des larves de Chilo partellus sur deux varietes de mais (“Inbred A”, sensible; “MP 704”, resistante). La consomation du tissus vegetale des deux varietes de mais est differente, tandis que ceci nest pas vrais pour le tissu nodal. Les extraits en solution aqueuse des deux varietes de mais causent une reduction de nourissement et du taux de croissance, et ces effets sont plus evident avec les extraits de MP 704 qu avec ceux de Inbred A. Cela demontre que MP 704 contient un facteur de retention deau qui reduit le taux de croissance. Les extraits en solution aqueuse des diverses varietes de mais se caracterisent par des variations de frequence sur les courbes de reponses des sensilles laterales. Les observations demontrent que la qualite de stimulation gustatif des deux varietes de mais est differente.