Location: Southern Insect Management Research Unit
Title: Life tables as tools of evaluation and quality control for arthropod mass production Authors
Submitted to: Elsevier
Publication Type: Book / Chapter
Publication Acceptance Date: March 22, 2013
Publication Date: November 21, 2013
Citation: Portilla, M., Morales Ramos, J.A., Rojas, M.G., Blanco, C. 2013. Life tables as tools of evaluation and quality control for arthropod mass production, pages 241-275. In J. A. Morales-Ramos, M. G. Rojas and D. I. Shapiro-Ilan [Eds.]. Mass Production of Beneficial Organisims: Invertebrates and Entomopathogens. Academic Press, San Diego, CA. Interpretive Summary: Construction of a life table is a simple method for keeping track of births, deaths, and reproduction. For arthropod life tables, parameters are basically calculated by recording deaths and births within a population on a daily basis, from the time that the first egg of an arthropod is born, to the time that all the arthropods, regardless of developmental stage, die. The formulae to calculate the important parameters of a life table are given in this chapter. Among the most important are net fecundity which indicates the number of females produced by a female at a given age, net reproductive rate which is the average number of offspring left by each female during their lifetime, and the finite rate of increase which produces a factor indicating how the population will increase every day. These three basic parameters can help while rearing high-quality arthropods because an alteration in any of them will allow us to determine optimal rearing conditions. How a life table is constructed, how these parameters can be interpreted, and their practical application, are presented with examples using different species of insects reared under laboratory conditions.
Technical Abstract: Life tables, as a basic concept, are descriptions of survival potential at various ages or stages. Understanding critical life stages of arthropod development and their influence on the population structure is of great importance for arthropod rearing systems. Another important advantage of a life table is that they summarize multiple life history parameters like immature survival, progeny sex ratio, development time, adult fecundity, and longevity by a single value defined as intrinsic rate of increase. The life table provides an overall evaluation of the impact of environmental factors or nutrients in all life history parameters at once. This chapter reviews the basic methodology of life table constructions and analysis with a particular emphasis in real cases of insect studies.