EFFECTS OF THE MS10 GENE, POLYGENES AND THEIR INTERACTION ON PISTIL AND ANTHER-CONE LENGTHS IN TOMATO FLOWERS

Pistil and anther-cone lengths (PL and AL) art important traits in tom ato hybrid seed production with the use of male-sterile flowers and in fruit production of fertile plants under high temperature. The effect s of the male sterility gene ms10, polygenes, and their interaction on tomato PL and AL and on the difference between them (DIF) were studie d in two experimental populations, each obtained from a different cros s and comprised of F-3 families derived from selfed heterozygous (Ms10 /ms10) F-2 plants. Data were analysed using a mixed model for a single gene, polygenes, and their interaction. The presence of the ms10 gene resulted in AL and PL that were shorter by 2.5 (+/-0.1) mm and 1.2 (/-0.1) mm, respectively, in male-sterile flowers than in male-fertile ones. Thus DLF was greater by 1.3 (+/-0.1) mm in male-sterile flowers than in male-fertile flowers. 'Main polygenic variance' was found in a ll three traits. The variance due to interaction between polygenes and the ms10 gene, even when significant, was always smaller than the var iance due to polygenes alone, or to environment. Emasculation of the m s10 male-sterile parent appears to be unavoidable for the efficient pr oduction of hybrid seeds.