Life table study of Sitotroga cerealella on different cereals and its implications on the performance of the egg parasitoid (Trichogramma chilonis) under laboratory conditions

AbstractSitotroga cerealellais one of the major pests of cereals in the field and storage conditions throughout the world. The main objective was to study the life tables ofS. cerealellaon wheat, maize and barley and its implications on percent parasitism ofTrichogramma chilonis.S. cerealellais reared under lab conditions as its eggs are utilized for rearingT. chilonis. Fresh eggs ofS. cerealellawere collected and after hatching the neonate larvae ofS. cerealellawere transferred onto each host plant species for obtaining first (F1) generation (G). Seventy eggs were used for each host and each egg was used as a replicate. Daily observations were made for recording the life-table parameters of theS. cerealella. The data showed that the developmental time ofS. cerealellaeggs and pupae was maximum (5.68 and 7.75 days) when reared on wheat, while the maximum larval duration (19.77 days) ofS. cerealellawas recorded on barley. The maximum fecundity (290.30 ± 22.47 eggs/female) was recorded on maize, while minimum fecundity per female was recorded on barley (159.30 eggs/ female). TheS. cerealellareared on maize had significantly higher values of finite rate of increase(λ),intrinsic rate of increase (r),and net reproductive rate (Ro)(0.14 ± 0.04 day− 1, 1.16 ± 0.05 day− 1, and 136.85 ± 20.25 eggs/ female) respectively. The mean generation time (T) (35.18 ± 0.61 days) was higher on wheat. Likewise, the gross reproductive rate (GRR) and the age-stage specific reproductive values (vxj) of newly oviposited eggs ofS. cerealellawere recorded higher (136.85 ± 20.25; 1.160 offspring) on maize. The data regarding the efficacy ofT. chilonisfor different parameters were recorded higher on maize i.e., percent parasitism (89.00 ± 2.30%), percent adult emergence (81.60 ± 1.20%), adult longevity (3.80 ± 0.10 days) and total adult longevity (9.90 ± 0.20 days) as compared to wheat and barley. Our findings revealed thatS. cerealellacan be best reared on maize under laboratory conditions as it prefers this host as compared to wheat and barley. Therefore, assigning the most susceptible and favorite host (maize) would help us to improveT. chilonismass production under laboratory conditions.