Detailed life tables and reproduction were studied in nymphs and adult females of Podisus maculiventris (Say) (Heteroptera: Pentatomidae) fed larvae of Galleria mellonella L. (Lepidoptera: Pyralidae) at constant temperatures of 18, 22, 26, and 30°C. Development rates were fitted to the equation Y = a b ln x. The theoretical development threshold was calculated as T0 = exp (−a/b), resulting in T0 = 12.48 and 12.78°C for females and males, respectively. Degree-days for development ranged from 233.92 in males at 18°C to 338.73 in females at 30°C. In all temperature treatments, P. maculiventris immatures consumed a mean of approximately eight prey items. Mean immature body weights were higher at higher temperatures, but females were heavier than males only at the fifth instar. In adult female P. maculiventris, age at first oviposition ranged from 2.7 d at 30°C to 13.4 d at 18°C. Percentage of egg hatch was lowest at 18°C (11%) and highest at 30°C (36.4%). Survivorship curves showed a linear decline with time, the steepest curves at the highest temperatures. Total number of eggs laid per female ranged from 429.4 at 18°C to 755.4 at 26°C. Mean egg numbers were fitted to a surface equation as eggs = (−6.658 0.432T) d exp(−0.002Td) where d and T are age (days) and temperature (°C), respectively. Net and gross reproductive rates were highest at 26°C (R0 = 379.126; gross reproductive rate [GRR] = 491.273 ♀/♀) and lowest at 18°C (R0 = 207.873; GRR = 294.972). Generation and doubling times were shortest at 30°C (T = 35.021 and DT = 4.270 d). Intrinsic and finite rates of increase were also highest at 30°C (r = 0.1623; λ = 1.1763). Reproductive parameters were recalculated using numbers of eggs that actually hatched, resulting in lower values, although the effects of temperature did not change. In the context of mass rearing P. maculiventris, 26°C is the optimal temperature tested, but female predators >21 d should be not be used because they may not be capable of laying viable eggs.
How to translate text using browser tools
1 October 2005
Life Table Analysis for Podisus maculiventris Immatures and Female Adults Under Four Constant Temperatures
Jesusa Crisostomo Legaspi,
Benjamin C. Legaspi,
Jesusa Crisostomo Legaspi
ACCESS THE FULL ARTICLE
It is not available for individual sale.
This article is only available to subscribers.
It is not available for individual sale.
It is not available for individual sale.
development
life history
reproduction
survivorship