Evaluation of an anthocorid predator, Blaptostethus pallescens against two-spotted spider mite, Tetranychus urticae (original) (raw)
Related papers
Biological Control, 2007
The two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) is one of the most important pests of many crops in temperate and tropical climates. Chemical control is the main method of combating this mite, but it is less preferred due to the development of resistance as well as environmental problems associated with the use of pesticides. Biological control of spider mites has been tried as a logical alternative method for chemical control. Studies have been conducted in different countries to assess the effect and potential of natural enemies for controlling the pest. The predatory mite Phytoseiulus macropilis (Banks) (Acari: Phytoseiidae) was found associated with spider mites in strawberry crops in the state of Minas Gerais, Brazil. Earlier studies suggested that P. macropilis was able to control spider mites, but predation and oviposition rates have not been measured so far. We measured predation and oviposition on strawberry with spider mites as prey in the laboratory. The predator fed on all prey stages and showed capacity to control local prey populations on leaf disks. The oviposition rate of P. macropilis is similar of the most used predatory mite Phytoseiulus persimilis and the predation rate is higher than that of the latter. Our results suggest that P. macropilis is a promising candidate to control two-spotted spider mites in the tropics and other areas.
Journal of Biological Control, 2019
The present study deals with the evaluation of anthocorid bug, Blaptostethus pallescens Poppius against Tetranychus urticae Koch on okra (Abelmoschus esculentus L.), conducted in Karif season (June-August) during 2013-2015 in the net cage condition at Entomological Research Farm, Punjab Agricultural University, Ludhiana. The 6-7 days old nymphs of B. pallescens @ 10, 20 and 30 nymphs/m 2 were released at weekly interval on the mite infested plants and these were compared with chemical control (Omite @ 300ml/acre at 10 days interval) and untreated control. The releases of predators and acaricidal spray on okra were found better than control in suppressing the population of T. urticae. The release of B. pallescens @ 30 nymphs/m 2 was found most effective with a 75.86 to 81.20 per cent reduction of mite population over control. It was statistically at par with chemical control, where 84.04 to 91.66 per cent reduction of mite population over control was recorded. There was no significant difference observed in the reduction of mite population of the plots released with 20 and 10 nymphs/m 2 of B. pallescens. The yield of okra from the plots of chemical control was recorded highest (52.70 q/acre), followed by 45.05 q/acre from the plots released with a B. pallescens @ 30 nymphs/m 2 at seven days interval. The study concluded that, integrating predator, B. pallescens @ 30 nymphs/plant along with acaricide (Omite 300 ml/acre) as a component of IPM for the management of two-spotted spider mite, T. urticae on okra under net house conditions.
University Journal of Zoology, Rajshahi University, 2009
Three predators Scolothrips sexmaculatus Pergande, Phytoseiulus persimilis Athias - Henriot and Stethorus punctillum Weise were used to control two-spotted spider mite, Tetranychus urticae Koch on potted bean plants. Mite population increased exponentially on the untreated plants, but on the predator treated plants, increase of mite population was checked and remained within minimum number. Early release of predator checked the mite population earlier and kept it lower than on late released plants. All the three predators may be used as bio-control agents against two-spotted spider mite. Key words: Control, Tetranychus urticae, Scolothrips sexmaculatus, Phytoseiulus persimilis, Stethorus punctillum and bio-control agents. Â doi:10.3329/ujzru.v27i0.1954 Univ. j. zool. Rajshahi Univ. Vol. 27, 2008 pp. 51-54
The functional response of the predator Typhlodromus negevi Swirski and Amitai fed on nymphal stages of Tetranychus urticae Koch was determined. A logistic regression of the proportion of prey consumed as a function of initial prey density to identify functional response types was conducted. Therefore, non-linear least-squares regression and the random predator equation to estimate attack rates and handling times were followed. Overall, all stages of T. negevi exhibited a type II functional response to T. urticae. Whereas, the attack rate (a) and handling time (T h ) of protonymph, deutonymph, and female of T. negevi recorded as 0.0329 and 2.0313, 0.0934 and 1.7918, and 0.1068 and 1.0796 when offered nymphal stages of T. urticae, respectively.
2018
Typhlodromus divergentis (Acari: Phytoseiidae) is a predatory mite of the family Phytoseiidae. Phytoseiid mites are known as one of the most promising biocontrol agents against spider mites. Biological studies of T. divergentis including preference of prey stage and predatory potential on Tetranychus urticae were conducted at CABI Biocontrol Laboratory, Directorate of Plant Protection, Agriculture Research Institute, Quetta, Pakistan. To conduct stage preference studies; different combinations of spider mites’ life stages i.e. (a) eggs + immatures (b) eggs + adults and (c) immatures + adults, were evaluated for larval, nymphal and adult stages of T. divergentis. The results suggested that eggs and immature stages of spider mites were preferred in all combinations for feeding by T. divergentis (larvae, nymph and adult stages). In case of predatory potential, each prey stage (egg, immature and adult) was provided separately to T. divergentis and maximum consumption of T. divergentis a...
Journal of entomology and zoology studies, 2020
A single 8 day's old nymph, mature female and mature male of anthocorid bug B. pallescens Poppius consumed an average of 9.2 10.0 and 10.0 eggs of two spotted spider mite, Tetranychus urticae Koch respectively, whereas similar stage of bugs consumed an average of 7.2, 9.8 and 9.4 eggs of European red mite, Panonychus ulmi (Koch) during a period of three days at 1:10 predator- prey ratio. Rate of consumption increased gradually in relation to increased predator- prey ratio up to 1:30. Data on consumption rate when denoted in terms of per cent host egg mortality was found declining gradually in relation to predator- prey ratio, both for two spotted spider mite and European red mite which was due to increasing chance of escape of host eggs from predation. Although potential feeding by all the stages of the bug used was positively correlated with prey density however result on was found varying at different predator- prey used. % host egg mortality by 8 day's old nymph, mature f...
In microcosm set-ups we investigated whether combined releases of the predatory thrips Scolothrips longicornis Priesner and two phytoseiid species, Neoseiulus californicus (McGregor) and Typhlodromus bagdasarjani Wainstein & Arutunjan provide better biological control of Tetranychus urticae Koch on cucumber plants than releases of each predator species alone. Results showed that control of T. urticae populations was equivalent under all predator combinations as in single predator release, indicating that no additive or synergistic effects among three predatory species had occurred in the control of the prey. In addition, the densities of each predator species under different combinations were similar, indicating that the three predators did not prey on each other during the observation period. Overall, our results showed that all three predator species are effective predators of T. urticae under microcosm conditions and suggest that they can be used in combination without decreased efficacy through intraguild predation.
2020
Predaceous insects is an effective important biological control agents of feeding on Tetranychus urticae Koch and decreasing the number during 2018 season to study the optimal predator: prey ratios for the release of Stethours gilvifrons (Mulsant) sacond larvae and adult stage for controlling the T. urticae on cottonplants Gossypium burbadense L. The obtained results showed that the effective control was gained after 12 days from released the second larvae and adult of the S. gilvifrons predatorwhen the predator: prey ratios were 1:15and1:25 respectively. The regression analysis between predator: prey ratios of S. gilvifrons (larvae and adults) reduction percentages cleared that there were negatively high relationship of larvae and adult predators and prey ratios, which means that the reduction rate was increased with lower predator : prey ratios and vice versa .The results assured that the best control of T.urticae populations under semi field conditions was cleared by using the l...
Entomophaga, 1985
Eight phytoseiid species were tested to evaluate and compare their potential as predators of Tetranychus evansi Baker & Pritchard and 7". urticae (Koch). The study was conducted using arenas of excised nightshade (Solanurn douglasii Dunal) and Lima bean (Phaseolus vulgaris L.) leaves infested with either Tetranychus species. When the prey was T. evansi, the predators Arnblyseius californicus (McGregor) and Phytoseiulus persirnilis Athias-Henriot from Ventura, California, showed the highest oviposition rates. However, those rates were 4 to 6 times lower than rates for the same predators feeding on T. urticae. Only A. californicus and the strain ofP. persimills from Beni-Mellal, Morocco, had survivorship higher than 50 % 8 days after the beginning of the experiment. The results indicated that T. evansi is an unfavorable prey for all the phytoseiids tested.