Literature cited: Kozik, E. 1993. Resistance to powdery mildew Oidium lycopersici in tomato. TGC report 43:26-27. Palti, J. 1988. The Leveillula mildews. In: "The Botanical review' 54: 423-535. Palti, J. 1959. Oidiopsis diseases of vegetables and legume crops in Israel. PL: Dis Rep., 39:277-279. Reuveni, R., Rotem, J. 1973. Epidemics of Leveillula taurica on tomatoes and peppers as affected by conditions of humidity. Phytopathol. Z, 76:153-157. Sidahmed, N.H. 1993. Powdery mildew resistance in Lycopersicon spp., M.Sc. thesis, Univ. of Gezira. Cactiflora (ccf), a novel proliferated flower mutant Rick, C.M. Department of Vegetable Crops, University of California, Davis, California 95616. This mutant (3-805) was encountered in our program of EMS mutagenesis. It bears close resemblance to a variant described in Genetics 30:374-362 (1945) and other in the intervening years, discovered as spontaneous unfruitful mutants in experimental and commercial fields and maintained clonally for several years. Since they did not appear in pedigreed families and were totally sterile, it was impossible to either maintain them via sexual reproduction or ascertain their inheritance. Patience again paid off, as this similar or identical cactiflora mutant was found in an M2 of EMS-treated cv. Castelemart. The mutant plants are normal in all respects except for an extreme modification of flower morphology, also reflected in the form of its (parthenocarpic) fruits. The flower is grossly fasciated with consequent increase in corolla and calyx segments. The center of the flower is transmogrified by a distorted fusing of androecium, gynoecium, and green tissue that tends to project beyond the normal position of reproductive parts as the flower ages. This jumble of parts often continues to develop into a fruit-like structure of considerable size, up to 8 cm diam., which results in a irregular distorted mass of fruit-like tissue, in which are imbedded anthers and other flower part, lacking seeds in every dissected example. The floral structures are large and persistent, rendering them more showy at a distance than + flowers. Since in every examination of cactiflora, male and female sterility was complete, the only mode of sexual transmission possible is via selfed heterozygous, yielding F2 segregations. Of four F3 families grown in 1993, two were completely normal, the other two segregated, yielding a total of 21 normal (+) plants and 5 ccf. Since this segregation does not deviate significantly from 3:1, it is assumed that cactiflora is determined by a single recessive gene, which we symbolize ccf.

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