Prey consumption of the predatory bug Dicyphus tamaninii Wagner (Heteroptera : Miridae) during nymphal and adult stages by feeding on Aphis gossypii Glover (Homoptera : Aphididae) as prey

摘要

The present study aimed to investigate the prey consumption by the predatory bug Dicyphus tamaninii Wagner (Heteroptera: Miridae) during its development as well as the entire longevity with 1-2- and 4-5-day-old Aphis gossypii Glover (Homoptera: Aphididae) as prey at a temperature of 25 +/- 1 degreesC and 18 +/- 1 degreesC. In total, D. tamaninii consumed during its development from the first nymphal instar (N-1) to the adult stage significantly more 1-2- rather than 4-5-day-old A. gossypii individuals, where it consumed at 25 +/- 1 degreesC in average 313 (femalefemale), 301 (malemale) aphids and 166 (femalefemale), 143 (malemale) aphids, while at 18 +/- 1 degreesC the prey consumption valued 618 (femalefemale), 533 (malemale) aphids and 309 (femalefemale), 224 (malemale) aphids of both age groups, respectively. The prey consumption by D. tamaninii adults over their entire longevity showed according to temperature, prey age group and sex of the predator significant variations. When 1-2-day-old A. gossypii individuals were offered, the total prey consumption was at 25 +/- 1 degreesC in average 844 (femalefemale), 494 (malemale) aphids and at 18 +/- 1 degreesC it valued 1611 (femalefemale), 700 (malemale) aphids, while with 4-5-day-old prey it valued at 25 +/- 1 degreesC in average 652 (femalefemale), 262 (malemale) aphids and at 18 +/- 1 degreesC it was 783 (femalefemale), 420 (malemale) aphids. The prey age preference by D. tamaninii with a mixed population of A. gossypii was also investigated. Results showed that significantly higher numbers of 1-2- rather than 4-5-day-old or adult aphids were killed by N-3, N-5 and adult stage of D. tamaninii.