Functional male sterility in tomato (Lycopersicon esculentum Mill.) and its application in hybrid seed production

Abstract

Advantages and disadvantages in using functional male sterility (positional sterile -ps, positional sterile 2 -ps 2, and excerted stigma -ex ) in tomato hybrid seed production and attempts to elaborate systems for their more efficacious use in breeding were discussed in this review. It was concluded that the application of one of these types of sterility, (ps 2) in practice, although in a limited number of countries, showed the functional male sterility in tomato was a potential not to be underestimated in developing approaches that aimed at reducting the time and cost associated with hybrid seed production.

High-resolution fine mapping of ps-2, a mutated gene conferring functional male sterility in tomato due to non-dehiscent anthers

“…The S. pimpinellifolium genetic background may be the reason for the incomplete positional sterility observed in those cases. InXuence of the genetic background for the expression of positional sterility 2 has already been observed by Atanassova (1999) within S. lycopersicum, where up to 26% self-pollination was observed in the most extreme cases, on cultivar "Vrbicanske nizke" (ps-2/ps-2) under Weld conditions during a hot summer. The most accurate phenotyping was performed on the recombinant subpopulation, by combining the observation of the anther appearance and its ability to release pollen, and the presence/ absence of seeded fruits.…”

“…Functional male sterility is characterized by a normal development of viable pollen that is not released for natural pollination due to abnormal morphology and functioning of the anthers (Georgiev 1991). One of the best characterized functional male sterility genes in tomato is positional sterility 2 (ps-2), originating from a spontaneous mutation in the Czech tomato cultivar "Vrbicanske nizke", which is characterized by non-dehiscent anther bags (Atanassova 1999). Its low level of self-pollination and the possible use of the viable pollen by manual anther opening render the ps-2 gene the most suitable male sterility gene for tomato hybrid seed production.…”

“…At least 19 tomato hybrid cultivars have been developed with the use of male sterility, mainly in Eastern Europe. Seventeen of them were based on the ps-2 gene (Atanassova 1999).…”

“…The mutant coi1 (Xie et al 1998) is insensitive to jasmonic acid, while the others are defective in jasmonic acid synthesis (Feys et al 1994;Ishiguro et al 2001;McConn and Browse 1996;Park et al 2002;Sanders et al 2000;Stintzi and Browse 2000;von Malek et al 2002). Atanassova (1999) observed up to 26% self-pollination in the most extreme cases, on cultivar "Vrbicanske nizke" (ps-2/ps-2) under Weld conditions. In contrast, no self-pollination was found in a ps-2 advanced breeding line (ps-2ABL) bred for this trait (data not shown), which means that the problem of self-pollination in ps-2/ps-2 lines can be overcome by breeding selection.…”

Study on the Potential of Genic Male Sterility in Tomato as a Tool for Pollen Flow Restriction

“…Structural mutants completely lack the pollen-bearing organs, or stamens, or have defects the in stamen form so severe that pollen is only rarely produced (16). Functional mutants produce viable pollen but have defects in flower structure that prevent effective pollen release (3,4). Sporogenious mutants produce no or scarcity of viable pollen (14).…”