Studies on the Tobamovirus resistance of the pepper (Capsicum annuum L.) cultivar Greygo

Abstract

Resistance of the Hungarian pepper (Capsicum annuum L.) cultivar "Gre.ygo" to Tohamoviruses has been investigated. All plants of the population of Greygo proved to be resistant to tobacco mosaic and tomato mosaic viruses (TMV, ToMV), both represent the pepper pathotypes Po of Tohamoviruses. Individuals of Greygo, however, were found to be susceptible to pathotypes P12 and P123 of pepper mild mottle virus (PMMV). When inoculated with the XM isolate of dulcamara yellow fleck virus (DYFV, pathotype P1) the population of Greygo segregated in resistant and susceptible plants. These results as well as inoculations of the progenies of three TMV resistant plants clearly showed, that besides the resistance allele Li the cultivar Greygo possesses also an another allele. This allele, provisionally marked by L2g behaves like to the allele L2 characteristic to Capsicum frutescens cv. . Tabasco. Determination of the identity of the allele L2g to the allele L2 needs further genetic and pathological informations. Relations between the Tohamoviruses pathogenic to pepper and the alleles of the resistance gene L are outlined for the discussion.

The Genes of Capsicum

“…Aniel Kumar et al, 2001 (Continued on next page) Fasciculation; compact, bushy plants with determinate tendency, short internodes; flowers and fruits borne in clusters; minor genes involved in the expression of fasciculation Greenleaf, 1986;Lippert et al, 1965;Van der Beek and Ltifi, 1990 fb M,f Fruit base nonbulging; nonbulged fruit base Miller and Fineman, 1938 Fc Filament color; filament color in anthers Prince et al, 1993 fcf** fc Fasciflora; female sterile plants with 27% to 55% pollen fertility, seedless fruits Daskalov and Poulos, 1994 fems* Female and male sterility; pollen shrunken, containing no starch; many small fruits with no seeds; mutant in line Ô4526Õ Martin and Crawford, 1951 fi-1 mutant-1, fi Filiform; threadlike leaves, blossom irregularities; female sterility Cook, 1961b;Lippert et al, 1965 fi-2 Filiform; similar to fi1; narrow cotyledons and leaves (3-4 mm); threadlike petals; carpels usually not fused to pistil except in particularly small fruited varietal background; incomplete female sterile Boukema et al, 1980b;Holmes, 1934Holmes, , 1937 Localization; localization of TMV resistance at high temperature; ÔCÕ for ÔCriollo de Moralos-334Õ; allelic at L locus Daubeze et al, 1990 L 2 L Localization; localization of both P 0 and P 1 strains of TMV in C. frutescens cv. Tabasco Boukema, 1980;Holmes, 1934Holmes, , 1937 (Continued on next page) Localization; this allele in ÔGreygoÕ behaves like the allele L 2 characteristic of ÔTabascoÕ; identity of the allele L 2g relative to L 2 is undetermined Salamon et al, 2001 L 3 Tm Localization; localization of P 0 , P 1 , and P 1.2 strains of TMV in C. chinense PIs Boukema, 1980;van den Berkmortel, 1997 L 4 Localization; localization of P 0, P 1 , P 1.2 and P 1.2.3 strain of TMV in C. chacoense accessions PI260429 and SA185; allelic series Daskalov and Poulos, 1994;Shuh and Fontenot, 1990 mos-1 to mos-52 Mosaics; cotyledons are either normal or display mosaic variegation of the leaves; mos-1 to mos-51 found in C. annuum, mos-52 in C. baccatum, nonallelism among mos-1 to mos-9 Csillery, 1980aCsillery, , 1983 ms-1 Genic male sterility; anthers are small and shrunken, devoid of pollen grains; ms-1 gene may be linked with one of the genes involved in pigmentation; mutant from ÔAll BigÕ Shifriss and Frankel, 1969;…”