Demographic characteristics of Paracoccus marginatus on papaya fruit and potato tubers with an innovative method for efficient application of the multinomial theorem in demographic research

The life table data of Paracoccus marginatus Williams and Granara de Willink reared on potato tubers and papaya fruit were collected and analyzed using the age-stage, two-sex life table. The preadult survival rate (sa = 0.61) and female adult longevity (28.6 d) on papaya fruit were significantly higher than in individuals reared on potato tubers (sa = 0.38 and 18.8 d). The female adult longevity was significantly longer than it was in male adults on both hosts. The net reproductive rate (R 0 = 206.72 offspring/individual), intrinsic rate of increase (r = 0.1745 d-1) and finite rate of increase (λ = 1.1912 d-1) of P. marginatus were significantly higher on papaya fruit than they were on potato tubers (R 0 = 37.29 offspring/individual, r = 0.1138 d-1, λ = 1.1221 d-1). Population projection indicated that the total population size of P. marginatus on papaya fruit could reach 146,826 individuals after 60 days, while the total population size of P. marginatus on potato tubers would only be 3,619 individuals. This study showed that P. marginatus had a higher fitness on papaya fruit than on potato tubers. We also discuss an innovative method for applying the multinomial theorem in demographic analysis based on the multinomial coefficients and individual compositions. To facilitate the application of the multinomial theorem in life table research including both fertile and infertile bootstrap samples, we calculated the exact multinomial coefficients for all possible individual compositions. A file for a sample size of 15 individuals (file size 4.07 GB) is made available for public access at DOI: 10.5281/zenodo.11257789.