Analysis of 3'-Terminal Region of Bean common mosaic virus Strains Infecting Common Bean in India

Differential expression of structural and functional proteins during bean common mosaic virus-host plant interaction

Bean common mosaic virus (BCMV), the most common seed-borne pathogen in Phaseolus vulgaris L. is known to cause severe loss in productivity across the globe. In the present study, proteomic analyses were performed for leaf samples from control (healthy) and susceptible BCMV infected plants. The differential expression of proteins was evaluated using two-dimensional gel electrophoresis (2-DE). Approximately, 1098 proteins were spotted, amongst which 107 proteins were observed to be statistically significant with differential expression. The functional categorization of the differential proteins illustrated that they were involved in biotic/abiotic stress (18%), energy and carbon metabolism (11%), photosynthesis (46%), protein biosynthesis (10%), chaperoning (5%), chlorophyll (5%) and polyunsaturated fatty acid biosynthesis (5%). This is the first report on the comparative proteome study of compatible plant-BCMV interactions in P. vulgaris which contributes largely to the understanding of protein-mediated disease resistance/susceptible mechanisms.

Identification and molecular characterization of Bean yellow mosaic virus infecting French bean in Himachal Pradesh

French bean (Phaseolus vulgaris L.), is one of the most widely grown vegetable crop. Disease samples showing yellow mosaic symptoms on leaves and pods were collected from Himachal Pradesh and inoculated on common bean cv. Jawala through sap inoculation. The virus successfully transmitted by mechanical inoculation produced yellow mosaic, leaf distortion, curling, wrinkling of leaves followed by stunting of plants. The identity of the virus as Bean yellow mosaic virus (BYMV) was established through Double antibody sandwich-enzyme linked immunosorbent assay, multiple sequence alignment and phylogenetic analysis of the coat protein gene sequence amplified by reverse transcription-polymerase chain reaction. The cp gene contained 819 nucleotides potentially coding for 273 amino acids. The sequence showed 83-99 % nucleotide and 89-99 % amino acid sequence identities with other BYMV isolates/strains and shared maximum identity with BYMV strain reported from Gladiolus sp. in Japan. This study constitutes the first report of BYMV occurrence on P. vulgaris in Himachal Pradesh.

Bean Common Mosaic Virus and Bean Common Mosaic Necrosis Virus: Relationships, Biology, and Prospects for Control

The closely related potyviruses Bean common mosaic virus (BCMV) and Bean common mosaic necrosis virus (BCMNV) are major constraints on common bean (Phaseolus vulgaris) production. Crop losses caused by BCMV and BCMNV impact severely not only on commercial scale cultivation of this high-value crop but also on production by smallholder farmers in the developing world, where bean serves as a key source of dietary protein and mineral nutrition. In many parts of the world, progress has been made in combating BCMV through breeding bean varieties possessing the I gene, a dominant gene conferring resistance to most BCMV strains. However, in Africa, and in particular in Central and East Africa, BCMNV is endemic and this presents a serious problem for deployment of the I gene because this virus triggers systemic necrosis (black root disease) in plants possessing this resistance gene. Information on these two important viruses is scattered throughout the literature from 1917 onward, and although reviews on resistance to BCMV and BCMNV exist, there is currently no comprehensive review on the biology and taxonomy of BCMV and BCMNV. In this chapter, we discuss the current state of our knowledge of these two potyviruses including fundamental aspects of classification and phylogeny, molecular biology, host interactions, transmission through seed and by aphid vectors, geographic distribution, as well as current and future prospects for the control of these important viruses.