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The mass production of widely used bio-control agent Trichogramma chilonis primarily depends on the constant supply of their host eggs and availability of suitable storage techniques. Experiments were conducted to develop such techniques of three Trichogramma chilonis Ishii strains (viz. Nilgiris, Kodaikanl and lab) on stored and un-stored Corcyra cephalonica eggs. Differential response was noticed when pupal storage was attempted on un-stored host eggs at 5 and 10 °C. At 10 °C (L: D- 8:16, RH-70 ± 10%), T. chilonis Nilgiris strain could retain its developmental arrest for the longest duration (60 days), followed by T. chilonis Kodaikanal (50 days). All the three tested strains showed a reduced storage capacity at 5 °C (L: D- 0:24, RH-70 ± 10%). However, T. chilonis Nilgiris and Kodaikanal strains could be stored for upto 35 days with 60% emergence rate and lab strain for upto 30 days where emerged adults could survive for 3 days. The study revealed that when stored host eggs are used, the parasitized cards (parasitoids in their pupal stage) are amenable for further storage of minimum 30 days at both 5 and 10 °C. To overcome seasonal fluctuation in host availability, stored C. cephalonica eggs can be used to store pupal stages of the three different strains of T. chilonis at 5 °C for a total duration of 50 days (host egg storage: 20 days + pupal T. chilonis storage: 30 days). [ABSTRACT FROM AUTHOR]

Rice moth, Corcyra cephalonica (Stainton) has been widely used as an efficient alternative host for the mass rearing of many biocontrol agents. With aim to increase production competence, egg dosages required for the initiation of its rearing culture were assessed. Each Corcyra rearing box containing 2.5 kg of milled sorghum was charged with different volume of eggs, i.e., 0.33 cc, 0.25 cc, 0.20 cc, 0.167 cc, 0.143 cc and 0.125 cc eggs and different parameters like larval period, first day to adult emergence, moth emergence, eggs production in F1 generation and fecundity per female were worked out. The larval period varied from 42 to 54 days and it increased with increase in volume of eggs per box. First adult emerged after 58.4 days in boxes charged with 0.33 cc eggs, which was significantly higher than other dosages (46.3 to 51.9 days). Moth emergence period in rearing boxes varied from 38 to 56 days in different dosages. Moth production per box (899.8 moths) was significantly higher at egg dosage of 0.20 cc followed by 0.25 cc, wherein 821.3 moths emerged. Similarly, egg collection in F1 generation was also maximum (8.63 cc) in boxes with initial dosage of 0.20 cc eggs per box, resulting in 43.15 fold increase as compared to volume of eggs used initially. In conclusion, the studies suggested that the optimal inoculative eggs for rearing of C. cephalonica should be 0.20 cc/box, each having 2.5 kg of milled sorghum for maximizing its production competence. [ABSTRACT FROM AUTHOR]

The growth-inhibiting properties of azadirachtin, a bioeffective triterpenoid compound isolated from neem ( Azadirachia indica A. Juss) seeds, was evaluated on the rice moth, Corcyra cephalonica Staint., a serious pest of stored products. By topical application of various azadirachtin doses (0.5 to 10 μg/larva) in methanol to last-instar spinning stage larvae, development was inhibited. The effect was dose-dependent; at higher doses, many of the insects remained in the larval stage (55% with 10 μg/larva). Disturbance of both larval-pupal and pupal-adult molting is discussed and interpreted as interference with the morphogenetic hormone pool size. [ABSTRACT FROM AUTHOR]