Spatiogenetic characterization of S receptor kinase (SRK) alleles in naturalized populations of Raphanus sativus L. var. raphanistroides on Yakushima island.

In various coastal areas of Japan, naturalized radish populations are observed. Radish is a cruciferous plant and exhibits self-incompatibility, involving a system controlled by a single locus with multiple S alleles. Although the S allele diversity of radish cultivars and wild radishes has been characterized, the S allele distribution in naturalized populations has not yet been analyzed in relation to the positions of the plants in situ.

Local boron concentrations in tuberous roots of Japanese radish (Raphanus sativus L.) negatively correlate with distribution of brown heart.

Internal browning (or brown heart) in radish is a physiological disorder, manifested as a reddish pigmentation in the central part of the tuberous root. Boron deficiency has been known to induce brown heart, but the relationship between B tissue concentration and the development of brown heart has not been tested. Here, we examined the relationship between these variables.

Physiological and genetic analysis of CO2-induced breakdown of self-incompatibility in Brassica rapa.

Self-incompatibility (SI) of the Brassicaceae family can be overcome by CO2 gas treatment. This method has been used for decades as an effective means to obtain a large amount of inbred seeds which can then be used for F1 hybrid seed production; however, the molecular mechanism by which CO2 alters the SI pathway has not been elucidated. In this study, to obtain new insights into the mechanism of CO2-induced SI breakdown, the focus was on two inbred lines of Brassica rapa (syn.

Mapping of the genes for dioecism and monoecism in Spinacia oleracea L.: evidence that both genes are closely linked.

Spinach is basically a dioecious species, with occasional monoecious plants in some populations. Sexual dimorphism in dioecious spinach plants is controlled by an allelic pair termed X and Y located on the short arm of the longest chromosome (x = 6). Ten AFLP markers, closely linked to the X/Y locus, were identified using bulked segregant analysis, four of which were revealed to co-segregate with Y in the present mapping population.

Novel self-compatible lines of Brassica rapa L. isolated from the Japanese bulk-populations.

Self-incompatibility (SI) in Brassicaceae is sporophytically controlled by a single S-locus with multi allelic variety. The male S determinant, SP11/SCR (S-locus protein 11/S-locus cysteine-rich protein), is a small cysteine-rich protein, and the female S determinant, SRK (S-locus receptor kinase), functions as a receptor for SP11 at the surface of stigma papilla cells. Although a few of the following downstream factors in the SP11-SRK signaling cascade have been identified, a comprehensive understanding of the SI mechanism still remains unexplained in Brassicaceae.