Legume pod borer (Maruca testulalis Geyer) and their relative yield losses in cowpea cultivars.

Field experiments were conducted at Chandra Shekhar Azad University of Agriculture & Technology, Kanpur during Kharif season of 2007–2008. One promising variety Pusa Komal and fourteen genotypes of cowpea were evaluated against major pests of cowpea legume pod borer (Maruca testulalis) were observed as major pests of cowpea at flower and pod stages of crop growth. The maximum population of pests was recorded as 0.83 pod borer larvae per flower bud at 91 DAS during second week of November and 2.18 per pod at 84 DAS during first week of November. The pod damage among the test cultivars varied from 22.8% to 32.56% by pod borers and genotype KCP-6 was least susceptible, whereas KCP-1 was most susceptible to this pest. None of the cultivars was found resistant to this pest. The varietal susceptibility to pod borer was found to be less in genotype KCP-6, Pusa Komal and RGC-5 and more in genotype KCP-1, RGC-2 and RGC-4. The maximum healthy and total pod yield was recorded in genotype KCP-2 (94.30 and 129.85 q ha−1) followed by genotypes RCP-4 (87.57 and 122.08 q ha−1). Contrarily, the minimum was recorded in Pusa Komal (50.55 and 67.07 q ha−1) followed by RCP-2 (51.34 and 70.08 q ha−1) and KCP-6 (64.07 and 83.00 q ha−1).