Effect of Different Temperatures on Consumption of Two Spotted Mite,Tetranychus urticae, Eggs by the Predatory Thrips,Scolothrips longicornis

Abstract

Environmental variables such as temperature are important factors affecting the efficacy of biological control agents. This study evaluated the predation rate of the predatory thrips Scolothrips longicornis Priesner (Thysanoptera: Thripidae) against the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) under laboratory conditions. Based on daily and total prey consumption of different life stages of S. longicornis on spider mite eggs at temperatures covering the range suitable for development and survival of the predator (15° C to 37° C, 60 ± 10% RH, 16:8 L:D), there was a significant effect of temperature on prey consumption. The number of prey consumed daily by first and second instar larvae increased linearly with increasing temperature from 15 °C to 37 °C, whereas daily consumption of preovipositing and postovipositing females was uninfluenced by temperature. Lower temperature thresholds for consumption by first and second instar larvae of S. longicornis was estimated to be 6.8 ± 0.04° C and 4.6 ± 0.03° C, respectively. The daily consumption of ovipositing females followed a nonlinear pattern, with maximum daily predation estimated at 32.8° C. From the model used to describe consumption of ovipositing females, an upper threshold for consumption of 41.4° C was estimated. The performance of S. longicornis at the different temperatures is discussed in relation to its practical use in integrated pest control programs.

Long‐term patterns of invertebrate abundance and relationships to environmental factors in arid Australia

“…Both Acarina and Thysanura showed positive relationships to average temperatures immediately prior to the survey. Acarina can increase prey consumption as ambient temperature increases (Pakyari & Enkegaard ), and general activity and capture rates would therefore be expected to increase as well. This may also be the case for Thysanura, although this seems less plausible as most Thysanura are nocturnal and actively avoid the soil surface if it is too hot (Cloudsley‐Thompson ).…”

Effects of photoperiod on development and demographic parameters of the predatory thripsScolothrips longicornisfed onTetranychus urticae

“…Newly hatched 1st instar larvae were moved individually to fresh leaf discs using what paintbrush. The larvae were fed every day with a surplus of spider mite eggs (about 100 prey items offered daily for each larva); the number of offered eggs was higher than the utilization capacity (Pakyari and Enkegaard, 2012). The leaf discs were renewed every 2 or 3 days until appearance of the last adult of S. longicornis .…”

“…The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), has a worldwide distribution attacking more than 900 type of host plant, including perennial and annual crops (Han et al ., 2003; Pakyari et al ., 2011 a ). T. urticae is difficult to control with insecticides (Naher et al ., 2005), due to short life cycle, unavailability of lower leaf surface, capacity to develop resistance to pesticides, and high reproductive capacity (Cranham and Helle, 1985; Pakyari and Enkegaard, 2012). Biological control plays a major role in managing spider mite populations, and comprise a range of taxa including predatory anthocorids (Heteroptera: Anthocoridae) (Cocuzza et al ., 1997), acarophagous ladybird beetles (Coleoptera: Coccinellidae), (Mori et al ., 2005), predatory mites (Acari: Phytoseiidae) (Gotoh et al ., 2004 a ), and acarophagous thrips (Thysanoptera: Phlaeothripidae, Aeolothripidae, Thripidae) (Sabelis, 1985; McMurtry and Croft, 1997).…”

“…Scolothrips longicornis shows all the life stages common to terebrantian thrips: the egg, two larval stages, prepupa, pupa and adult, with longevity varying according to temperature, photoperiod, and prey species. The prey consumption rate of this predator in their lifetime is about 300 eggs of T. urticae (Pakyari and Enkegaard, 2012). Some aspects of the biology of S. longicornis (life table characteristics, mutual interference, functional response, and prey consumption) have been established (Gerlach and Sengonca, 1986; Sengonca, 1988; Pakyari et al ., 2009; Pakyari and Enkegaard, 2012), but to date, the effect of photoperiod on development and life table has not been examined.…”

Effect of Temperature on Demography and Predation Rate of Menochilus sexmaculatus (Coleoptera: Coccinellidae) Reared on Phenacoccus solenopsis (Hemiptera: Pseudococcidae)

“…Being poikilothermic organisms, the development, reproduction and predatory potential of insects is affected to a great extent by temperature variations in the environment. Insects perform best only at a certain temperature range (Roy et al, 2002;Rana, 2006;Pakyari and Enkegaard, 2012). Life table studies of a predator at varying temperatures can provide detailed information about survivorship, development, mortality and life expectancy Rizvi, 2007, 2008).…”