A widespread leaf deformity disease of mentha (mint), accompanied by whiteflies, the vectors of begomoviruses, was observed in Punjab in the last few years. The presence of begomovirus was indicated by DNA dot-blot analysis using the conserved coat protein and replicationassociated protein genes of another begomovirus, Sri Lankan cassava mosaic virus (SLCMV). A DNA fragment (2.0 kb), representing a partial genomic DNA of a begomovirus, amplified from the symptomatic mentha leaves was used to design end-primers and further amplify an additional 0.9 kb fragment, representing the remaining portion of the resident viral DNA. The two sequences, assembled together (2.7 kb), showed that they represented the complete sequence of an isolate of Tomato leaf curl Karnataka virus (ToLCKV) DNA. Using universal betasatellite primers, a 1.4 kb fragment was amplified from the same sample. This cloned DNA fragment showed complete sequence identity with the previously reported Cotton leaf curl Multan betasatellite (CLCuMB). Majority of the symptomatic mentha leaf samples, collected from four districts of Punjab, showed cross-hybridization in DNA dot-blot using cloned SLCMV and CLCuMB DNA, indicating the presence of one or more begomoviruses related to SLCMV and the betasatellite, CLCuMB. The begomovirus and betasatellite could be mechanically transmitted to Nicotiana benthamiana. Whitefly transmission of the resident begomovirus could also be demonstrated on mentha. The evidence indicates the association of ToLCKV and CLCuMB, a hitherto new combination of a begomovirus and a betasatellite associated with a leaf deformity disease in mentha in Punjab.

Experiments were conducted at farmer’s cabbage fields to evaluate the bioefficacy of anthranilic insecticide i.e. E2Y45 20 SC (Chlorantraniliprole) having novel mode of action against the diamondback moth Plutella xylostella L. E2Y45 20 SC was applied @ 25.0, 37.5 and 50.0 ml/ha and was compared with Padan 50 SP (cartap hydrochloride) @ 500 g/ha and the untreated control. Lowest mean larval population after two sprays was recorded in higher dose of E2Y 45 20 SC i.e. @ 50.0 ml/ha (0.08 larvae/plant) at 7 days after treatment followed by medium and lower dose of E2Y 45 20 SC i.e. @ 37.5ml/ha (0.10 larvae/plant) and 25.0 ml/ha (0.33 larvae/plant). The larval population in these treatments was significantly lower than standard check, Padan 50 SP (2.56 larvae/plant), and untreated control (9.73 larvae/plant). The highest marketable yield (262.89 q/ha) was recorded in E2Y 45 20 SC @ 50.0 ml/ha which was significantly higher than Padan 50 SP (239.65 q/ha). Lowest yields were recorded in untreated control (106.00 q/ha). Conclusively, medium (37.5 ml/ha) and higher (50.0 ml/ha) dose of E2Y 45 20 SC (chlorantraniliprole) significantly reduced the larval population of P. xylostella and increased the cabbage yield.

No abstract