PHOTOMORPHOGENIC RESPONSES TO UV RADIATION III: A COMPARATIVE STUDY OF UVB EFFECTS ON ANTHOCYANIN and FLAVONOID ACCUMULATION IN WILD-TYPE and aurea MUTANT OF TOMATO (Lycopersicon esculentum MILL.)

Genetic studies carried out since 1958, have revealed at the sulfurea (sulf) locus of Lycopersicon esculentum the occurrence of a particular type of genetic instability: somatic conversion (paramutation). In vegetative cells of sulf+sulf heterozygotes the wild type allele sulf+ is heritably altered under the influence of the mutant sulf allele which is present in the same nucleus.By crossing sulf homozygotes and seven primary trisomics of the tomato (triplo-2, -5, -7, -8, -9, -10, -12) as well as a tertiary trisomic it was proven that the sulf locus is on chromosome 2, the nucleolus chromosome of the tomato.The effects of dosage are shown by the two different heterozygous trisomics which differ with regard to somatic conversion. In sulf+sulf sulf plants somatic conversion takes place very frequently; 60% of the plants (35) are variegated; that is, two conversion-active sulf alleles are very frequently able to convert one sensitive sulf+ allele. However, in sulf+sulf+sulf plants conversion has so far not been found; all plants (52) are entirely green; that is, one conversion-active sulf allele acting against two conversion-sensitive sulf+ alleles is not able to induce somatic conversion.

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Genetic analysis of the dwarf curly leaf tomato mutant via hybridization with Curl and dwarf mutants

Genome ◽

10.1139/g89-455 ◽

1989 ◽

Vol 32 (3) ◽

pp. 359-364

Author(s):

M. H. Yu

Keyword(s):

Lycopersicon Esculentum ◽

Genetic Analysis ◽

Fruit Size ◽

Seed Number ◽

Wild Type ◽

Epistatic Effects ◽

Lycopersicon Esculentum Mill ◽

Majority Group ◽

Tomato Mutant ◽

Curly Leaf

The characteristics of the dwarf curly leaf tomato (Lycopersicon esculentum Mill.) mutant, cu-3, were investigated via hybridization with the Curl, Cu, and dwarf, dcr, mutants. When Cu plants were crossed to cu-3 or dcr parents, F1 plants expressed the Cu phenotype, whereas two parental and two nonparental types were present in each F2. The transgressive groups were the wild type (+), which developed normal expanded leaves, and the midvein-invisible type (MI), which developed extremely distorted curly leaves. Crosses between cu-3 and dcr plants produced nonparental wild-type plants in F1, and two parental and one wild type in F2. There was no allelism or linkage between cu-3 and Cu, dcr, or dpy (the dumpy mutant). Cu was epistatic to both cu-3 and dcr. The cu-3 allele was epistatic to dcr; however, dcr plants (in the cu-3+cu-3 dcr dcr genotype) could produce cu-3 progeny. The cu-3 plants always bred true, cu-3 hindered the Cu-type progeny from becoming a majority group in Cu and cu-3 hybridizations. Both cu-3 and cu-3+ caused >33% decrease in fruit size of Cu, dcr, +, and MI progeny of their Cu and dcr hybrids; a >50% decrease in seed number per fruit was evident in such progeny of the cu-3 hybrids.Key words: Lycopersicon esculentum Mill., L. pimpinellifolium (Jusl.) Mill., epistatic effects, recombinant types, transgressive groups.

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