Establishment of a Faba Bean Banker Plant System with Predator Orius strigicollis for the Control of Thrips Dendrothrips minowai on Tea Plants under Laboratory Conditions

The stick tea thrip Dendrothrips minowai (Priesner) (Thysanoptera: Thripidae) is a destructive pest in tea plantations in south and southwest China. To control this pest, a non-crop banker plant system was developed using a polyphagous predator Orius strigicollis (Poppius) (Heteroptera: Anthocoridae) with the black bean aphid Aphis fabae (Scopoli) (Hemiptera: Aphididae) as an alternative prey and the faba bean Vicia faba as the banker plant to support the predator in targeting the pest. The fitness of A. fabae on tea plants and faba bean was evaluated to determine its host specificity. Moreover, the control efficacy of the banker plant system on D. minowai on tea plants was tested in the laboratory and compared with that of direct release of O. strigicollis. The experiments showed that faba bean was an excellent non-crop host for A. fabae because, while the aphid population increased quickly on faba bean, it could only survive for up to 9 days on tea plants. Compared with direct release of O. strigicollis, lower densities of pest were observed when introducing the banker plant system. Our results indicate that this banker plant system has the potential to be implemented in the field to improve the control of the pest thrips.

Development and Fecundity of Orius minutus (Hemiptera: Anthocoridae) and O. laevigatus Reared on Tetranychus urticae (Acari: Tetranychidae)

The polyphagous predator Orius species is a dominant predator of thrips, mites, and aphids. Orius laevigatus (Fieber) is a well-known commercialized and effective biological control agent, whereas Orius minutus (L.) distributed widely over the world has not been commercialized. To assess potentials of developing O. minutus as a commercial biological control agent, we compared the biological parameters of O. minutus with O. laevigatus when reared on mixed stages of Tetranychus urticae Koch at 27.5°C. Nymphal development of O. laevigatus was shorter (11.30 d) than that of O. minutus (12.25 d), but there was no significant difference in survivorship between the two species. Also, no significant difference was found in either the preoviposition or oviposition periods, lifetime fecundity, or longevity between the two species. However, O. minutus eggs had a higher hatch rate (0.77) than O. laevigatus (0.71). In life table analysis, no difference was found in any parameters, i.e., R0, rm, λ, T, and DT, between O. laevigatus and O. minutus in two-tailed t-tests. In a predation bioassay, O. minutus consumed 1.39 times more adult T. urticae in 24 h than did O. laevigatus, although the predation rate on T. urticae eggs was similar between the two species. These results suggest that O. minutus native to Korea could be developed as a biological control agent against T. urticae.

The Occurrence of the Polyphagous Predator Orius niger (Wolff) (Hemiptera, Anthocoridae) in Greece

[no abstract available]

Feeding Efficiency of Green Lacewing, Chrysoperla carnea (Stephens) against Different Species of Aphid in Laboratory Conditions

Green lacewing, Chrysoperla carnea Stephens (Neuroptera: Chrysopidae) is the most effective polyphagous predator of different species of aphids and is commonly known as “aphid lion” . The experiment on feeding efficiency of green lacewing was studied in the laboratory of Entomology Division, NARC, Khumaltar, Lalitpur, Nepal from 21st , December 2015 to 26th, March 2016. The known number of predatory larva of green lacewings were fed with known number of seven different species of live aphid and frozen Corcyra eggs representing each treatment. The treatments were replicated four times. The predatory efficiency was calculated by counting the number of consumed host per day. The result revealed that the predatory efficiency of C. carnea larvae were increased from first to third instar and third instar were more voracious as compare to first two instars. It consumed significantly the highest rice moth, Corcyra cephalonica followed by Aphis craccivora and others aphid species, respectively. From this experiment, it is evident that the green lacewing is potent bio-agent against different aphid species and hence further research is required simultaneously in the farmer’s field conditions.Int. J. Appl. Sci. Biotechnol. Vol 5(1): 37-41

Natural prey of the lynx spider Oxyopes lineatus (Araneae: Oxyopidae)

The natural prey of the lynx spider Oxyopes lineatus Latreille, 1806 was studied in a meadow in the subtropical zone of Azerbaijan. The percentage of specimens of O. lineatus found while feeding was low (4.3%). Spiders were observed feeding both day and night. The investigation has shown that O. lineatus is a polyphagous predator feeding on a wide range of arthropods, with representatives of nine arthropod orders found in its diet. The primary food of O. lineatus was Diptera, Hymenoptera, and Homoptera, which collectively made up about three quarters of all prey. Worker ants constituted about 20% of the diet suggesting that O. lineatus is a myrmecophagic spider. The length of prey killed by O. lineatus ranged between 0.50 and 8.50 mm (mean 2.72 mm), varying from 12.1 to 171.4% (mean 61.4%) of the length of their captors. The most frequently captured prey were arthropods not exceeding the length of the spiders (87.5%).