Effect of diet, photoperiod and cold on Eurygaster integriceps Puton diapause (Hemiptera: Scutelleridae)

Abstract : Sunn pest (Eurygaster integriceps Put.) (Hemiptera: Scutelleridae), is a serious pest of cereals causing severe quantitative and qualitative by feeding on leaves, stems and grains. Aim of the current study was to evaluate the effect of photoperiod and diet on the Sunn pest diapause. Thus, the effect of two photoperiod conditions including short day (8 L: 16D) and long day (16L: 8D) and two diet including wheat grains and growing wheat plants on stadium duration, gonad size and haemolymph protein concentration was examined. Also, to extend our studies the effect of cold on gonad size and haemolymph protein concentration was studied. Results showed that stadium duration in short day photoperiod condition (31.43 days) was shorter than long day photoperiod condition (38.58 days) (P<0.05) i.e. when the nymphs were placed in short day conditions and fed on wheat grains their development time (time taken to adult) was shortened about 15?16 days in compare with those nymphs that placed in long day conditions and fed on wheat plants. Short day photoperiod condition and wheat grain diet caused larger ovary size (4.08±0.48 mm2) than long day conditions and wheat plant diet (3.12±0.04 mm2). Cold exposed females and males had lower haemolymph protein concentration than control females and males. The results showed that although photoperiod and diet cause significant changes on the stadium duration, ovaries and testis size and haemolymph electrophoretic bands, their distinct effects on diapause needs to be elaborated more
Keyword : Sunn pest, Diapause, Diet, photoperiod, cold
Author(s) : , A. Amiri, A. R. Bandani, A. Moslemi-Mehni
Downloads : 1148

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