| abstract |
The present invention relates to a recombinant potyvirus infectious nucleic acid, preferably cDNA or RNA, construct useful for plant cross protection, comprising a full length clone characterized in that its HC-Pro gene conserved FRNK box sequence contains a substitution, preferably a substitution of Arg. Preferably, the construct further contains a substitution which effectively abolishes aphid transmissibility. The present invention further relates to a method for the production of a mild strain of potyvirus utilizing the above mentioned construct and to a method for protecting plants from viral infection and for transient expression of foreign nucleic acid (genes) in plants, using said construct. Preferably, the present invention relates to a method for cross protection of curcurbits against ZYMV infection. The present invention also relates to a method for providing protection against viral infection in plants comprising inoculating plants, by mechanical inoculation or by bombardment, with the recombinant potyvirus infectious construct. |