تأثیر انواع مختلف سبزیجات برگی روی شاخص‌های تغذیه‌ای کرم برگ‌خوار پنبه،Spodoptera littoralis (Boisd) (Lepidoptera: Noctuidae)

The Egyptian cotton leafworm, Spodoptera littoralis (Boisd) (Lepidoptera: Noctuidae), is the important pest and polyphagous that causes considerable damage to agricultural products in Iran and many parts of the world. In current research, the effects of seven different leafy vegetables, including Perpin, Chives, Parsley, Basil, Dill, Coriander and Mint hosts assessed on feeding indices of various instar S. littoralis larvae individually in a growth chamber at 25 ± 1°C, 60 ± 5% RH, and a photoperiod of 16:8 (L:D) hours. The data were analyzed via one-way analysis of variance (ANOVA) using the statistical software of SPSS ver. 22. The statistical differences among means of various bean cultivars were compared through Turkey’s post hoc Honestly Significant Difference (HSD) test at α= 0.01. The results showed that significant differences were observed in the nutritional properties of S. littoralis fed on fresh leaves from the different vegetables. The highest whole larval instars weight, larval gain weight and feces produced values were achieved Basil host (52.59, 17.01 and 49.56 mg, respectively), and the lowest were obtained on Chives host (37.55, 9.98 and 5.18 mg, respectively). In addition, the highest values of food consumed was detected on the Perpin vegetable (89.61 mg), and the lowest was observed on the Chives vegetable (23.52 mg). The lowest and highest approximate digestibility (AD) value was on Basil (30%) and Perpin (91%) hosts, respectively. Furthermore, the highest efficiency of conversion of ingested food )ECI) and efficiency of conversion of digested food (ECD) came from larvaes that fed on Chives (43%) and Coriander (88%) vegetables. Also, the lowest values of ECI and ECD were observed on Perpin host (12 and 13.5%, respectively). The lowest value of relative consumption rate (RCR) was observed on Parsley host (0.16 mg/mg/day) and the highest value was on Perpin vegetable (0.45 mg/mg/day). In addition, the highest and lowest values of relative growth rate (RGR) were found on Dill (0.09 mg/mg/day) and Perpin (0.05 mg/mg/day) vegetables. According to the results of this study, Dill and Coriander vegetables were susceptible and the most suitable hosts for S. littoralis. In contrast, the Perpin host were found the relatively resistant, least appropriate, host for this pest which could be useful in development of integrated pest management strategies and plant-herbivore interactions.