Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/1/2004
Publication Date: 10/1/2004
Citation: Legaspi, J.C. 2004. Life history of Podisus maculiventris (Heteroptera: Pentatomidae) adult females under different constant temperatures. Environmental Entomology. 33(5):1200-1206. Interpretive Summary: The spined soldier bug is native throughout North America and has been found in various crops, including soybean, alfalfa and corn. Because it feeds on over 75 insect species including several important pests, the spined soldier bug is reared and sold commercially in Europe and North America. Despite much research interest in this bug, relatively few studies about how its populations may change with time and environment, and how this influences its usefulness as a biological control agent, have been done. Scientists at the USDA-ARS Center for Medical, Agricultural and Veterinary Entomology in Tallahassee, FL, determined spined soldier bug longevity and reproduction at various temperatures. They discovered that egg production was particularly sensitive to temperature. This information will help predict the usefulness of the spined soldier bug at different seasons of the year and improve the efficacy of mass-rearing.
Technical Abstract: Life table analysis was performed on Podisus maculiventris (Say) adult females at constant temperatures of 16, 26, 30 and 36 C. Survivorship curves were linear Type II, with steeper rates of decline at higher temperatures. Longevity at 16 C (47.2 d) was significantly longer than that at 26 C (14.3 d) or 30 C (12 d). Adults under the 35 C survived only 4.9 d and laid no eggs. Percentage of eggs that hatched was relatively constant at 40% at 16, 26 and 30 C. Numbers of egg clutches (ranging from 5.9 to 9.4), eggs per clutch (13.6 to 14.6), and eggs in the first clutch (9.0 to 15.1) did not differ significantly at these three temperatures. However, preoviposition period was significantly longer at 16 C (20.3 d) than at 26 C (6.3 d) and 30 C (4.9 d). Number of eggs laid was related to body weight by the equation E = -139.1 + 3.49 w where E is number of eggs laid per female lifetime, and w is the weight of the predator female. Life table analysis of P. maculiventris female adults showed that both net reproductive rate (R0) and gross reproductive rate (GRR) were highest at 26 C, estimated at 47.8 and 156.0 females/female, respectively. However, the shorter generation times at 30 C (T = 42.2 days) resulted in higher values for the intrinsic rate of increase (r = 0.09), the finite rate of increase (l = 1.09), and doubling time (DT = 7.7 days).