Field screening of some long duration pigeonpea [Cajanus cajan (L.) Millsp.] genotypes against the infestation of Pod bug, Clavigralla gibbosa (Spinola) and gram pod borer, Helicoverpa armigera (Hubner)

Abstract

Twenty-five long duration pigeonpea genotypes were screened for the reaction against pod bug and gram pod borer during Kharif season of 2014-15 at the Agricultural Research Farm, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi. The first incidence of pod bug, Clavigralla gibbosa (Spinola) was observed in 4th standard week and continued to 12th standard week in all genotypes The population of pod bug was found to be highest in genotype Bahar (check) and ICP 7035-1 in 11th standard week with population of 10.3 bugs/plant and 10.2 bugs/plant, respectively. The mean population of pod bug was recorded highest in genotypes Bahar (check) and ICP 7035-1 i.e. (6.8 bugs/plant) and lowest in genotype ICP 13212-1 (3.0 bugs/plant). The first incidence of pod borer, Helicoverpa armigera (Hubner) larvae was observed in 4th standard week in fifteen genotypes out of the total twenty-five genotypes. The mean population of pod borer was recorded highest in genotype ICP 13198-1 i.e. (1.1 larvae/plant) followed by Bahar (check), ICPL 97253 and ICPHaRL 4985-4 (1.0 larvae/plant) and no incidence of pod borer was recorded in genotype ICPHaRL 4985-10 and ICPL 20062. The highest per cent pod damage caused by Clavigralla gibbosa (Spinola) was found in ICP 7035-1 (26.0 per cent), followed by ICPHaRL 4985-11 (21.5 per cent) and ICPL 88039-1 (21.0 per cent). The per cent pod damage inflicted by Helicoverpa armigera (Hübner) ranged from nil in genotypes ICPHaRL 4985-10 and ICPL 20062 to 5.5 per cent in genotype ICP 13198-1. The genotype ICP 13198-1 (5.5 per cent) showed higher per cent pod damage as compared to check, Bahar (5.0 per cent). Whereas, all other genotypes showed lower per cent pod damage as compared to Bahar (5.5 per cent). The genotype ICPHaRL 4985-4 showed 5.5 per cent of pod damage similar to the check (Bahar). The per cent grain damage caused by Pod bug on different genotypes ranged from 1.96 per cent in genotype ICP 13212-1 to 16.97 per cent in genotype Bahar (check cultivar). The per cent grain damage due to lepidopterous pod borer on different genotypes varied from nil in genotypes ICPHaRL 4985-10 and ICPL 20062 to 3.03 per cent in genotype ICPHaRL 4989-7. Due to the adverse weather conditions that prevailed during the crop season, a very low grain yields were recorded. The grain yield of different genotypes differed significantly and ranged from 105.6 kg/ha in the genotype ICPL 85063 to 338.9 kg/ha in ICP 7035-1.