Food Ingestion and Utilisation Efficiency of Legume Pod Borer,Maruca vitrataGeyer (Lepidoptera: Crambidae) on Different Pulse Hosts

Abstract

The legume pod borer, Maruca vitrata (Geyer) (Lepidoptera: Crambidae), is an important pest of pulses globally. The laboratory study investigated its development, survivorship and food intake on different pulses, namely pigeon pea (CO RG 6), black gram (CO BG 6), green gram (CO GG 7), cowpea (CO 7) and lablab (Rohini) in an environment of 27.9±2.2 °C and 76.6 ± 9.1%RH. The highest food consumption was recorded in lablab flowers (433.02 mg) while the maximum larval weight gain was in pigeon pea flowers (71.85 mg). The maximum assimilation rate (375.33 mg) was in flowers of lablab. The relative growth rate was maximum in flowers of black gram (2.27) and whereas efficiency of conversion of digested food was 36.60 % and efficiency of conversion of ingested food was highest on green gram flowers (72.96 %). An attempt on mass-culturing was made on its natural hosts and as per the studies, the culture could be maintained only up to first generation on all hosts except lablab. The results of the first-generation study revealed that, in lablab, the maximum number of Maruca larvae (38.2) successfully completed with the maximum pupation rate (71.1 %) and adult emergence (81.5 %). It was found that lablab was able to support four to six generations under laboratory conditions and the sex ratio (male:female) of 1:2 had the maximum number of eggs laid (86) on lablab. The results of significant differences among the hosts indicated that lablab was highly suitable host for rearing of M. vitrata.