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The sugar beet flea beetle, Cassida vittata Vill. is an invasive pest that significantly damages sugar beet crops in Morocco by affecting the leaves. To gain a deeper understanding of how temperature influences the development and reproduction of C. vittata and to facilitate its population management, laboratory-based experiments were conducted. Individuals were subjected to a range of constant temperatures spanning from 15 °C to 36 °C. The most extended lifespans for both adult females and males were recorded at 30 °C, with respective longevities of 62.8 and 62.5 days. The highest likelihood of eggs maturing into the adult stage occurred at 25 °C, with survival rates of 39.0% for females and 37.5% for males. Preadult survival rates displayed significant variability with temperature, with the highest survivorship observed at 25 °C (76.5%). The maximum average number of offspring produced per female reached 225.1 eggs at 25 °C. Daily reproduction, maximum total fecundity, and maximum daily fecundity were also notably higher at 25 °C. The population growth parameters exhibited their most favorable values at 25 °C, with r (0.0933 d−1), and R 0 (87.15 offspring per female) being highest at this temperature. The temperature thresholds for the complete pre-adult stage (1st instar larva to adult) were estimated to be 9.4 °C for females and 9.0 °C for males. The thermal constants from the 1st instar larva to the adult stage were calculated to be 526.3 and 476.2 DD, respectively. These findings indicate that the most favorable temperature range for the population growth of this invasive pest falls between 25 °C and 30 °C. [Display omitted] • Life table parameters of C. vittata were evaluated at 15, 20, 25, 30 and 36 °C. • The lowest total preadult mortality and highest fecundity were obtained at 25 °C. • Intrinsic and finite rate of increase and net reproductive rate were highest at 25 °C. • The thermal constants of females and males were 526.3 and 476.2 DD, respectively. • The optimal temperature for population growth of C. vittata is suggested at 25–30 °C. [ABSTRACT FROM AUTHOR]

Diaspis echinocacti (Bouché), is a notorious pest that infests cacti, causing serious damage. The developmental durations of various life stages, sex ratios, survival rates, fecundity, and population growth parameters of D. echinocacti were studied under temperature conditions ranging from 15 °C to 40 °C. Temperature significantly influenced the developmental periods, with the shortest durations observed at 25 °C. A decrease in female life cycle duration was observed from 15 °C (83.2 days) to 32 °C (26.4 days). Higher temperatures led to a decrease in the proportion of females in the population, with a sex ratio of 0.10 at 40 °C. Pre-adult survival rates showed an 83% survival rate at 25 °C which sharply declined to 21% at 32 °C and 7% at 40 °C. Parthenogenesis was not observed in females. Total pre-oviposition, and post-oviposition periods decreased with increasing temperature, with the longest oviposition period at 25 °C (37.7 days). The intrinsic rate of increase (r) was highest at 25 °C (0.09 d−1). Predicted fecundity for the next generation was highest at 25 °C (9947.2), followed by 20 °C (2349.0). The population trend index indicated a potential population increase of 49.7 times at 25 °C in the next generation. The estimated temperature threshold for the egg-to-adult development of females and males in D. echinocacti was 10.5 °C. For the cumulative development of females and males from egg to adult, the thermal constants were 400.0 DD and 357.1 DD, respectively. These findings highlight the effect of temperature on scale development, with implications for scale management. [Display omitted] • Life table parameters of D. echinocacti were evaluated at 15, 20, 25, 32 and 40 °C. • The lowest total preadult mortality and highest fecundity were obtained at 25 °C. • Intrinsic and finite rate of increase and net reproductive rate were highest at 25 °C. • The thermal constants of females and males were 400.0 and 357.1 DD, respectively. • The optimal temperature for population growth of D. echinocacti is suggested at 20–32 °C. [ABSTRACT FROM AUTHOR]