Age-Stage, Two-Sex Life Tables of the 24 Spot Ladybird [(Subcoccinella vigintiquatuorpunctata (Coleoptera: Coccinellidae)]

HIGHLIGHTS

• Subcoccinella vigintiquatuorpunctata is one of the main pest on alfalfa.

• Age-specific life table and survival rate for each life stage was calculated by using TWOSEX-MSChart.

• This study suggest the life table can be used for the biology and control of the alfalfa pest.

Abstract

The life cycle of Subcoccinella vigintiquatuorpunctata (L.) (Coleoptera: Coccinellidae), which is an important pest of alfalfa (Medicago sativa Linnaeus (Fabales: Fabaceae) has been studied in laboratory conditions with a constant temperature of 25±1 ºC, relative humidity of 65±2% and light period of 16:8 hours. TWOSEX-MSChart was used to determine the parameters of the life table. The development stages of the egg to adult were recorded separately according to sex (female/male). The development duration of female and male individuals was found to be respectively, egg, 6.61±0.18, 5.45±0.19 days; first instar larvae, 4.58±0.16, 4.21±0.20 days; second instar larvae, 3.61±0.14, 3.21±0.17 days; third instar larvae, 2.81±0.14, 2.48±0.14 days; fourth instar larvae, 6.32±0.17, 6.03±0.17 days; pupae stage, 5.84±0.14, 5.34±0.11 days; total development time, 29.77±0.44, 26.72±0.41 days. In addition, the adult preoviposition (Apop) of the pest was 310.95±0.19 days; total preoviposition (Tpop) 340.33±0.59 days, the average number of eggs laid was 343.23±43.3; oviposition period was 29.71±0.7 days; the number of eggs laid per day was determined as 12.31±0.37. Adult longevity was found 265.68±29.5 and 292.69±28.2 days in female and male individuals, respectively. Among the population parameters, the intrinsic rate of increase (r) was 1.39 d^-1. Net reproductive rate (Ro), 143.783 progeny/individual, the mean generation time (T) 355.547 days; Total reproductive rate (GRR) 249.764 females/females; finite rate of increase (λ) was calculated as 1.01 d^-1. It shows that the data from the life table created with the results obtained can be used for the biology and control of the pest.

Keywords:
Subcoccinella vigintiquatuorpunctata; population parameters; alfalfa.