A Successful laboratory mass rearing system of Spotted pod borer, Maruca vitrata (Crambidae: Lepidoptera) on a blackgram based semi-synthetic diet

Abstract To mass rear M. vitrata under laboratory conditions, a study was carried out and aimed to develop a blackgram based semi-synthetic diet (D-B). Comparison of several biological, reproductive and digestive parameters for three successive generations of M. vitrata reared on four different semi-synthetic diets viz., D-J, D-JR, D-NEW, blackgram based semi-synthetic diet (D-BAS) along with blackgram natural diet was successfully attempted. Larvae fed on blackgram based semi-synthetic diet (D-BAS) recorded the shortest developmental time (29.37 days), the highest food consumption (64.21 mg) and fecal production (20.83 mg) resulting in the maximum larval and pupal weights (48.46 and 47.11 mg, respectively). The insects fed on D-NEW and blackgram natural diet recorded the longest developmental period (32.90 and 34.48 days) with minimum larval weights (44.03 and 48.64 mg) and pupal weights (40.39 and 49.43 mg), respectively. The highest per cent pupation (82.53), adult emergence (78.22), larval (6.50) and pupal growth index (12.86) was recorded on larvae fed with blackgram based semi synthetic diet (D-BAS). The highest sex ratio (1.81) and fecundity (43.94 eggs) were recorded on blackgram semi-synthetic diet (D-BAS). The highest Relative Consumption Rate (0.23 gg− 1day− 1), Relative Growth Rate (0.084 gg− 1day1), Relative Metabolic Rate (0.073 gg− 1day− 1), Approximate Digestibility (67.49%) and Metabolic Costs (46.51%) lowest Efficiency of Conversion of Ingested Food (36.09%) and Efficiency of Conversion of Digested Food (53.49%) were recorded on blackgram semi-synthetic diet (D-BAS).