Modeling Thermal Developmental Trajectories and Thermal Requirements of the Ladybird Stethorus gilvifrons

Abstract

The development rate of the predatory ladybird, Stethorus gilvifrons (Mulsant), fed on Tetranychus urticae Koch, was determined at 15, 20, 25, 27, 30, 34, and 38 °C. The total development time from egg to adult emergence for females was estimated to be 61.4, 31.6, 14.4, 13.3, 12.5, and 11.7 days, respectively. The development time decreased with increasing temperature from 15 to 34 °C, but all eggs failed to hatch at 38 °C. The lower temperature threshold (T0) for the entire development period and the thermal constant (K) for female S. gilvifrons were estimated to be 11.64 °C and 194.50 degree-days (DD) using the common linear model, and 11.96 °C and 187.87 DD using the Ikemoto and Takai model, respectively. Data were fitted to 20 non-linear development rate models and the thermal thresholds (Tmin and Tmax) and optimal temperature (Topt) were estimated. Among non-linear models, the Briere-2 and Ikemoto and Takai linear model provided adequate descriptions of the temperature-dependent development of S. gilvifrons. The upper-temperature threshold was estimated to be about 44 °C using the Logan-10 non-linear model. The estimated thermal development characteristics can be used to predict the occurrence and the population dynamics, as well as to improve the mass rearing and release, of S. gilvifrons for the biological control of T. urticae.

Effects of Temperature and Host Plant on Hedgehog Grain Aphid, Sipha maydis Demographics

“…In addition, the relationship between temperature (T) and developmental rate (r = 1/d) for the pre-reproductive time was modeled using linear regression, using the formula Dr = a + bT, where Dr is the development rate (days−1) and T is the temperature ( • C) [27] within a temperature range in which the relationship was linear (15 to 30 • C). The lower temperature threshold (T0) and the thermal constant (K, degree-days) were determined using the parameters: T0 = −a/b and K = 1/b [28].…”

Thermal Oviposition Performance of the Ladybird Stethorus gilvifrons Preying on Two-Spotted Spider Mites

“…Both the plastic containers and plastic dishes were stored in growth chambers programmed at 15, 20, 25, 27, 30, and 34 °C (all ± 1 °C), 50 ± 5% R.H and a photoperiod of 16:8 h (L:D). The numbers per individual cohort (age < 24 h) at the starting point of the experiments were 200, 140, 120, 120, 120, and 120 eggs at the above temperatures [ 25 , 36 ]. Progress in development (hatching, molting, pupation, adult emergence) and survival were assessed every 24 h [ 23 , 36 ].…”

“…The numbers per individual cohort (age < 24 h) at the starting point of the experiments were 200, 140, 120, 120, 120, and 120 eggs at the above temperatures [ 25 , 36 ]. Progress in development (hatching, molting, pupation, adult emergence) and survival were assessed every 24 h [ 23 , 36 ]. Due to juvenile survival varying with temperature [ 25 ], the number of adult females emerging at the above temperatures was 10, 20, 29, 33, 33, and 38 individuals.…”

“…In previous studies [ 25 , 36 ], we assessed the effect of temperature on the life history of S. gilvifrons [ 25 ] and simulated the thermal developmental trajectories using linear and non-linear models [ 36 ]. Here we aimed at describing the thermal oviposition performance of S. gilvifrons by using four non-linear models [ 37 , 38 , 39 , 40 , 41 ] and comparing their fit to experimentally observed fecundity data at six constant temperatures [ 25 ].…”

Correction: Jafari et al. Modeling Thermal Developmental Trajectories and Thermal Requirements of the Ladybird Stethorus gilvifrons. Insects 2023, 14, 11

“…Following the publication of [ 1 ], we detected some errors in Tables 1, 4 and 5. Table 1 reported an incorrect formula for the third-order polynomial model; Tables 4 and 5 contained a few incorrect numerical values.…”