Urdbean leaf crinkle infection in relation to plant age, seed quality, seed transmission and yield in urdbean

The susceptibility of urdbean plants to leaf crinkle disease decreased with increase in plant age, while the incubation period increased with the increase in plant age at the time of inoculation. Sap inoculation of urdbean plants at weekly interval significantly affected the texture, colour and size of urdbean seeds and a number of shrivelled, off-coloured, oversized and undersized seeds were observed in such seed lots. Seeds from infected plants exhibited varying range of reduced germination as well as seed transmission of urdbean leaf crinkle inoculum into next season. The seed borne inoculum was found responsible for adversely affecting the various yield contributing factors as well as yield of urdbean.