Assessing the potential for biological control of potato field pests in Ardabil, Iran: functional responses of Orius niger (Wolf.) and O. minutus (L.) (Hemiptera: Anthocoridae)

Abstract

The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), and the onion thrips, Thrips tabaci Lind. (Thysanoptera: Thripidae), are significant field pests of potato in the Ardabil region of Iran. Orius niger (Wolf.) and O. minutus (L.) (Hemiptera: Anthocoridae) are locally the predominant natural enemies of these pests. This study compared the functional responses of O. niger and O. minutus to female mites and second instar thrips larvae across a range of prey densities (5, 10, 20, and 40 prey/arena) under controlled conditions of 24 ± 1°C, 50 ± 5% RH and 16:8 h (L:D). The resulting data were appropriately fit to Type II functional response models in four predator-prey interactions, including: (1) O. niger to second instar thrips larvae (a = 0.009 h -1 ; and T h = 1.62 h); (2) O. niger to females mites (a = 0.006 h -1 and T h = 1.28 h); (3) O. minutus to second instar thrips larvae (a = 0.008 h -1 and T h = 1.93 h) and (4) O. minutus to females mites (a = 0.01 h -1 and T h = 1.1 h). The number of second instar thrips larvae attacked by O. niger was greater than that by O. minutus (P B 0.01); conversely, the number of females mites attacked by O. minutus was greater than that by O. niger (P B 0.01). These results confirm the potential for both O. niger and O. minutus to make valuable contributions to a biological control program against onion thrips and the two-spotted spider mites infesting potato fields in this region.

Basic Studies Aiming at Orius minutus (Hemiptera: Anthocoridae) Mass-Rearing

“…The present study was conducted to establish a mass-rearing technique for improving the usability of Orius minutus (L.), an indigenous Asian species that is expected to show effective control in agriculture, because it is already adapted to domestic environments. Previous studies reported the potential of O. minutus as a biological control of aphids, leaf mites, and diamondback moths (Plutella xylostella (L.) (Lepidoptera: Plutellidae)) [13][14][15][16]. We also verified the predatory ability of the two-spotted spider mite (Tetranychus urticae Koch (Acari: Tetranychidae)), which was 1.39 times higher than that of O. laevigatus [17].…”

Understanding trophic interactions of Orius spp. (Hemiptera: Anthocoridae) in lettuce crops by molecular methods

“…There are many laboratory predation studies of Orius spp. on thrips, as well as some under field conditions in the Mediterranean basin and the Middle East . However, very little is known about Orius spp.…”

Effect of Temperature on Functional Response ofAphidius gifuensis(Hymenoptera: Braconidae) ParasitizingMyzus persicae(Hemiptera: Aphididae)

“…At all 4 temperatures, linear parameters (P 1 ) were negative (Table 1), showing that the functional responses were type II. A type II functional response has been found by many scientists with other insect species under various conditions (Bernal et al 1994; De Clercq Zamani et al 2006;Fathi & Nouri-Ganbalani 2009). Holling (1959 stated that invertebrates display a type II functional response whereas type III is found in vertebrate predators, but later this idea was rejected because parasitoids can also display a type III functional response.…”