Development of green shield bug (Palomena prasina L., Heteroptera: Pentatomidae) in different temperatures
Özet
Green shield bug (Palomena prasina L., Heteroptera: Pentatomidae) is a very common pest species in Turkish hazelnut orchards. This pest feeds on hazelnut fruits and causes premature nut dropping in early season and causes kernel damage toward post season. In this study, development periods and thermal thresholds of eggs and nymph stages were investigated in laboratory conditions at 16, 20, 24 and 28 degrees C. The nymphs were fed on common bean seeds (Phaseolus vulgaris L.). The seeds were replaced every two days. The egg hatching periods were 12.38 +/- 0.18, 8.23 +/- 0.14, 6.82 +/- 0.06 and 5.47 +/- 0.07 days and hatching ratios of eggs were 82.9 +/- 10.27% (46-100), 97.8 +/- 1.43% (93-100), 96.4 +/- 2.71% (86-100) and 90.7 +/- 4.61% (75-100) respectively, depending on temperatures. At 16, 20, 24 and 28 degrees C, egg hatching lasted 2-4, 1-3, 1 and 1 days respectively. The nymphal periods were 83.80, 66.73, 48.40 and 33.87 days, and development ratios of nymphs were 20, 44, 40 and 24% respectively depending on temperatures. Thermal thresholds were 14.06 degrees C and 8.67 degrees C for egg and nymphal stages respectively, and 9.54 degrees C for all development period. Thermal constants were 69.93 day-degree for egg stage, 666.66 day-degree for nymphal stage and 769.23 day-degree for the total development period including egg and nymphal stages.
