Effects of constant and variable temperatures on development and reproduction of the two-spotted spider mite Tetranychus urticae (Acari: Tetranychidae)

Abstract

We focused on the influence of different temperature amplitudes on development and reproduction of the two-spotted spider mite, Tetranychus urticae Koch, at a 16:8 (L:D) h photoperiod and 60-95 % RH. The temperature amplitudes varied from 0 to 24 °C in steps of 6 °C; i.e. 22 ± 0, 22 ± 3, 22 ± 6, 22 ± 9 and 22 ± 12 °C. Temperature changed every 24 h between a low and an upper value, but without changing the average temperature (22 °C). The number of eggs laid by five females for 24 h was slightly lower at 22 ± 12 °C than at constant temperature (22 ± 0 °C), and egg hatchability differed among the five temperature regimes. Developmental time at 22 ± 0 °C was shorter than that at 22 ± 3 and 22 ± 6 °C, but longer than that at 22 ± 9 and 22 ± 12 °C. The oviposition period, total fecundity per female and adult longevity gradually decreased with increasing amplitudes. Sex ratio was similar at all five temperature regimes. The intrinsic rate of natural increase (r m) was affected by temperature amplitude and the r m-values at all amplitudes except 22 ± 12 °C were higher than that at constant temperature. Thus, this study showed that variable temperature regimes influence population growth rates of T. urticae and that large amplitude regimes are stressful for this species.

Effects of constant and fluctuating temperatures on development and reproduction of Megoura crassicauda and Aphis craccivora (Hemiptera: Aphididae)

“…However, fluctuating temperatures are more relevant ecologically as compared to the temperatures that organisms actually experience daily and seasonally in the field (Lamb 1961, Hagstrum & Hagstrum 1970 and in greenhouses (Tantau 1998, Pollet et al 2009. In fact, many biological characteristics of insect and mite species, including body size (Beck 1983, Bahar et al 2012, survival rate (Colinet et al 2006& 2007, Carrington et al 2013, Gotoh et al 2014, developmental time (Niederegger et al 2010, sex ratio (Vangansbeke et al 2013), female fecundity (Hagstrum & Leach 1973, Carrington et al 2013, population growth rates (Mironidis & Savopoulou-Soultani 2008, Vangansbeke et al 2013 and immune function (Karl et al 2011) can differ greatly when organisms are reared at fluctuating temperatures compared to constant temperatures. The mechanisms responsible for these developmental differences that occur at fluctuating versus constant temperatures are not completely known (Worner 1992, Liu et al 1995, Vangansbeke et al 2015.…”

Identification of long non-coding RNAs in the immature and mature rat anterior pituitary

“…Therefore, the relevant molecular mechanisms in reproduction development should be more of a research focus. Reproduction development contains extensive content and is regulated by many factors, such as hormones, essential micronutrients, and temperature 14 – 18 . Several recent studies have reported that lncRNAs perform an important role in reproduction.…”

Diurnal Temperature Variations Affect Development of a Herbivorous Arthropod Pest and its Predators

“…urticae has shown to be a successful alternative for chemical control [ 36 – 38 ]. Recently, the influence of temperature variations on both pest and predators has been investigated [ 39 , 40 ], revealing a substantial impact on their development, fecundity and population growth. Here, we explored the developmental rates of the mite species under a wider range of temperatures at different DTRs.…”