Mass screening for varietal resistance to bacterial leaf streak was rapidly and efficiently carried out by using a portable motorised high pressure power-spray. Twenty eight-day-old seedlings, planted in pots (5" diameter x 4") were sprayed with inoculum twice from the base. Readings were taken 12 days after inoculation. A modification of the technique which included the use of wet nursery bed instead of pots, with seedlings planted in rows and spaced three inches apart, was recommended for routine mass screening. It was recommended that seedlings be inoculated twenty-one days after sowing. Inoculation by the copper-gauze technique on twenty-eight-day-old seedlings was found to be simple and efficient in inducing symptoms, but it was time-consuming and laborious if large number of varieties and genetic lines were to be screened. The sandpaper and the poly-spray techniques were found to be inefficient for routine mass screening. The technique of flooding seedling base did not induce any infection.

 

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