The influences of larval and adult food quality on the calling rate and pre-calling period of females of the cotton bollworm, Helicoverpa armigera Hubner (Lepidoptera : Noctuidae)

Pre-calling behavior of female adults of Helicoverpa armigera reared on art ificial diet (Insecta LF) during the larval stage and fed on water and hone y solutions (5, 10 and 20%) was observed. The quality of the adult diet did not influence the distribution of the pre-calling period (PCP). However, t he calling rate was significantly higher in the three honey-fed groups (100 %) than in the water-fed group (87.5%). In the next experiment, pre-calling behavior of female adults that were reared on Insecta LF during the larval stage and fed on 10% honey solution starting from different days after eme rgence was observed. The delay of adult feeding did not influence the calli ng rate, although the PCP was slightly prolonged in individuals which were not fed on honey solution until the onset of night 3 or night 5 (night 0=ni ght of adult eclosion). In the experiment in which larvae were fed on diffe rent qualities of food (cotton leaf, okra fruit and Insecta LF), the callin g rate varied greatly depending on the adult diet. When fed on honey soluti on, almost all adults called irrespective of their larval diet. However, wh en fed on water only, the calling rate of adults fed on Insecta LF during t he larval period was 60.4%, while those of adults fed on cotton leaf and ok ra fruit were only 16.7% and 33.3%, respectively. These results indicate th at most female adults of H. armigera can attain reproductive maturity even without feeding on nutritious diets when provided with highly nutritious di ets during the larval period and most female adults can not attain reproduc tive maturity without feeding on nutritious diets when provided with low nu tritive value diets during the larval period.