BOTH COMMON AND SPECIFIC GENETIC-FACTORS ARE INVOLVED IN POLYGENIC RESISTANCE OF PEPPER TO SEVERAL POTYVIRUSES

Absolute resistance to potato virus Y pathotype 0 (PVY 0), potyvirus E and chili veinal mottle virus (CVMV) and a partial resistance to pota to virus Y pathotype 1,2 (PVY 1,2) were found in an Indian pepper line ,'Perennial'. In the doubled haploid (DH) progeny from the F-1 of a cr oss 'Perennial' by 'Yolo Wonder', resistance to CVMV was confered by t wo independent genes, one with a clear dominant effect. Resistance to PVY and potyvirus E was quantitatively expressed and controlled by sev eral recessive genetic factors. Genetic analysis showed that fewer res istance factors were necessary to explain resistance to PVY(0) and pot yvirus E than resistance to PVY(1,2). Genetic correlations between res istances to the different potyviruses in the DH progeny showed that mo st of genetic factors involved in PVY(0) resistance appear to be also involved in potyvirus E resistance, and some of these polyvalent facto rs may be also involved in PVY(1,2) resistance but, in this case, addi tional specific genes were necessary. One of the two CVMV resistance g enes seems to be implicated in potyvirus E resistance. Thus, the polyg enic resistance of 'Perennial' to these potyviruses was due both to po lyvalent genetic factors: i.e. factors that apparently interact with s everal viruses, and strain-specific genetic factors.