Temperature-dependent development of Oenopia conglobata (Col.: Coccinellidae) fed on Aphis gossypii (Hem.: Aphididae)

Abstract

Ladybeetles are known beneficial insects, with a long history in augmentative and classical biological control. The ladybeetle Oenopia conglobata (L.) is a natural enemy of many herbivores, particularly aphids. The temperature-dependent development of O. conglobata was studied at six constant temperatures (22.5, 25, 27.5, 30, 32.5 and 35 °C) to understand its development rate and environmental constraints better. Linear and nonlinear (Lactin) models were fitted to the data. In the thermal range from 22.5 to 32.5 °C, the rate of development increased for all stages; 35 °C was lethal for all stages and no eggs hatched. The Tb and K values for the biological cycle (egg–adult) were 8.84 °C and 263.15 DD, respectively. Depending on the model, tmin values for the total development time of the coccinellid ranged from 8.45 to 8.82 °C. The nonlinear model of Lactin estimated the optimum and upper temperature thresholds for the total development time of the ladybeetle to be 33.2 and 35.0 °C, respectively. High R2 values and low residual sum of squares values revealed a good fit to the experimental data for total development and different developmental stages of O. conglobata. The results may contribute to the improvement of practical methods for mass rearing of O. conglobata.

Molecular characterization of DNA methyltransferase 1 and its role in temperature change of armyworm Mythimna separata Walker

“…Obviously, the DNA methylation inhibitor (5‐aza‐dC) are broad spectrum, in consideration of multiple subtypes of DNA methyltransferase that have not yet been discovered in oriental armyworm, it is probable that they can affect many MsDnmt s signaling pathways including MsDnmt1 . Temperature change affect the larval development duration, generally the M. separata exhibited longest time from larval to pupae stage under high temperature (Figure 6d), this situation is also consistent with other insects (Jalali, Sakaki, Ziaaddini, & Daane, 2018; Kobori & Hanboonsong, 2017). Besides, injection of DNA methylation inhibitor (5‐aza‐dC) leads to shortened duration time of the last instar to pupae under 36°C (Figure 6d).…”

“…| 11 of 14 larval development duration, generally the M. separata exhibited longest time from larval to pupae stage under high temperature (Figure 6d), this situation is also consistent with other insects (Jalali, Sakaki, Ziaaddini, & Daane, 2018;Kobori & Hanboonsong, 2017). Besides, injection of DNA methylation inhibitor (5-aza-dC) leads to shortened duration time of the last instar to pupae under 36°C (Figure 6d).…”

Effects of temperature on the fitness of the alfalfa weevil (Hypera postica)

“…We predicted the occurrence of H. postica at different developmental stages, taking the estimated values of t min and K from the linear model into account, as previously reported 42,43,58,59 . The occurrence of late‐stage larvae at the beginning of the productive cycle (late March) increases the risk of damage caused by this pest 5,29,60,61 .…”

“…18 4.5 Phenology and the damage risk period of H. postica in the Ebro basin We predicted the occurrence of H. postica at different developmental stages, taking the estimated values of t min and K from the linear model into account, as previously reported. 42,43,58,59 The occurrence of late-stage larvae at the beginning of the productive cycle (late March) increases the risk of damage caused by this pest. 5,29,60,61 Previous studies have suggested that H. postica produces more than one generation under the conditions in the Ebro basin, 5,29 thus affecting both the first and second alfalfa intercuts.…”