The impact of fruit and leaf of six pistachio varieties on feeding indices of Helicoverpa armigera

The cotton bollworm has been considered as a threatening pest in pistachio orchards in Kerman province especially in Sirjan.  In this study, the nutritional indices of the third instar larvae reared on leaves and fruits of six pistachio varieties including Ahmad Aghaei, Akbari, Ohadi, Jandaghi, Kalehghochi and Momtaz. Experimental containers, containing one larvae and one fruit or leaf incubated at growth chamber with 22±2°C, 55±5% RH and a photoperiod of 16:8 (L: D). The weight of larvae, feces and consumed fruits and leaves were calculated every 24 hours. Data were analyzed by one-way ANOVA using SPSS software. The results showed significant differences in all larval nutritional indices on studied pistachio varieties. The lowest values of efficiency of conversion of ingested food (17.87±0.87%) and the lowest of efficiency of conversion of digested food (21.73±0.69 %) were observed on fruits of Ohadi variety. Also, the lowest of efficiency of conversion of ingested food (11.87±0.89 %) and the lowest of efficiency of conversion of digested food (15.43±0.88 %) were observed on leaves of Ahmad Aghaei variety. Based on the cluster analysis resuls, the highest values of nutritional indices were observed in larvae feeding on fruits of Momtaz, Jandaghi and Kaleghohi varieties. The lowest values were obtained on larvae reared on fruit and leaf of Ohadi and leaf of Ahmad Aghaei varieties.