Molecular Detection of Bean Yellow Mosaic Virus in Lupinus albus Plants and its Associated Alterations in Biochemical and Physiological Parameters

Bean yellow mosaic virus is one of the most devastating diseases of cultivated Leguminosae plants worldwide causing mosaic, mottling, malformation and distortion in infected cultivar plants. Present study was conducted to investigate the possibility of infection of Lupinus albus (Lupine) with Bean yellow mosaic virus. Virus isolate was identified by detection of the coat protein gene amplified by reverse transcription polymerase chain reaction and also via Chenopodium Amaranticolor as a diagnostic host plant. Results showed that infection can be induced under greenhouse conditions and infected plants showed a considerable level of mosaic symptoms. As disease development in infected plants is always associated with physiological and chemical changes, some metabolic alterations parameters have been evaluated like photosynthetic pigment contents, total carbohydrate content, total soluble protein, total protein, total free amino acid, proline induction, total phenolics, salicylic acid, and abscisic acid content in healthy and infected lupine plants. Results showed a great variation in all the biochemical categories in Lupinus albus infected with bean yellow mosaic virus as compared to healthy plants. Chlorophyll a of virus inoculated Lupinus albus decreased to 27%, whereas Chlorophyll b content decreased to 19.5% and carbohydrate content decreased to 36% when compared to healthy control plant corresponding values. Results also showed many metabolic changes in virus infected Lupine plants. The effect of virus infection on the induction of plant growth regulators like abscisic acid was determined, as well as the relationship between abscisic acid activation, accumulation of the virus, and symptoms development was discussed, and the effect of abscisic acid inhibitor application on virus infection and Lupine primary and secondary metabolism was elucidated, as this effect is a neglected field of research.