*Department of Mycology and Plant Pathology, Dr Y S Parmar University of Horticulture and Forestry, Nauni, Solan (H P)
Division of Plant Quarantine, NBPGR, Pusa Campus, New Delhi
National Symposium on “Plant Pathology in the Changing Global Scenario” held at National Bureau of Plant Genetic Resources, New Delhi on February 27–28, 2009
Bell pepper is an important commercial crop of H P belonging to family Solanaceae mainly grown under protected cultivation. Unfortunately the crop falls prey to number of pests including pathogens among which the virus diseases assume special importance by causing huge economic losses and reduce the interstate export potential. In different bell pepper growing districts of Himachal Pradesh virus disease incidence ranged between 1–100 per cent. Thirty geographic isolates were categorized into two distinct groups of potyvirus (C-I) and cucumovirus (C-II) based on serological relationships and reaction on set of indicator plants. Two representative isolates from each group were further categorised and identified on the basis of host range, transmission, particle morphology,cytopathology and serological relationship. C-I isolate showed relationship with PVMV and C-II isolate with CMV in DAS and DAC- ELISA test. Virions of C-I and C-II isolates showed good clumping with PVMV and CMV antisera, respectively, but not with antisera of TEV and PVY used in studies on ISEM. Detection of C-I isolate by employing RT-PCR with the use of potyvirus group specific primers (P9502 and CPUP) resulted in amplified product of 800 bp. Based on the identification parameters C-I (tested by serological and molecular means) and C-II(tested only serologically) isolates have been identified to be the strain of PVMV and CMV, respectively. For the management of virus(es) effect of leaf extract of Mirabilis jalapa and Asparagus adscendens was studied. Data revealed that aqueous leaf extracts at 5 per cent and 10 percent concentration of both the plant species had significantly reduced the virus transmission in pre and post inoculation treatments besides simultaneous application. Extract of Mirabilis jalapa when sprayed at a concentration of 10 per cent resulted in enhancing the incubation period of 12 days. The per cent disease transmission was minimum (44.25%) at 10 per cent concentration applied along with inoculation.
