The chromosomal location of phosphatase isozymes of the wheat endosperm

Analysis of introgression of Aegilops ventricosa Tausch. genetic material in a common wheat background using C-banding

Seven Triticum aestivum (cv. Moisson)-Aegilops ventricosa addition lines and four VPM-1 lines were studied by C-banding, and compared with the parental common wheat cultivars Marne-Desprez (hereafter Marne), Moisson, and A. ventricosa lines 10 and 11. All of the VPM-1 lines had similar C-banding patterns and carried the same major 5B:7B translocation as the parental Marne cultivar. According to the C-banding analysis, the VPM-1 lines carry a complete 7D(7D(v)) chromosome substitution and a translocation involving the 5D and 5D(v) chromosomes. However, the translocation of the 2N(v)/6N(v) chromosome of A. ventricosa to the short arm of the 2A chromosome of wheat that had been identified in an earlier study using molecular analysis (Bonhomme A, Gale MD, Koebner RMD, Nicolas P, Jahier J, Bernard M in Theor Appl Genet 90:1042-1048, 1995; Jahier J, Abelard P, Tanguy AM, Dedryver F, Rivoal R, Khatkar S, Bariana HS Plant Breed 120:125-128, 2001) was not detected in our study. However, the appearance of a small pAs1 site at the tip of the chromosome 2A short arm in VPM-1 could be indicative of a minor translocation of the A. ventricosa chromosome. The 5B:7B translocation was also found in all seven T. aestivum-A. ventricosa addition lines, although it was not present in the parental common wheat cultivar Moisson. These lines showed different introgression patterns; besides the addition of the five N(v)-genome chromosomes, they also possessed different D(D(v)) genome substitutions or translocations. A whole arm translocation between chromosome 1N(v) and 3D(v) was identified in lines v86 and v137, and also in the A. ventricosa line 10. This observation lends further support to the idea that A. ventricosa line 10, rather than line 11, was used to develop a set of wheat A. ventricosa addition lines.

A comparative study on variability and phylogeny of Triticum species : 1. Intraspecific variability

Intraspecific variability of A, S and D genome diploid species and AAGG and AABB allotetraploid species of the genus Triticum was examined in a comparative study using isoenzymatic characters (peroxidases of embryo plus scutellum, and endosperm; and alkaline phosphatases) of dry mature seeds. The methodology followed was based on the definition of variables from characters and three functions related with total intraspecific, intrapopulational and interpopulational variabilities. The diploid species with the greatest intraspecific variability were speltoides and longissimum, and among the allotetraploid species, timopheevii. Concerning all variables, interpopulational variability was found to be greater than intrapopulational in urartu, monococcum, timopheevii, dicoccoides and sharonensis. Intraspecific variability differences found among species are discussed with reference to Nevo (1978) and a hypothesis concerning intraspecific variability differences between allotetraploids is suggested. The final objective of the present paper is to provide information on intraspecific variability differences among species for future use in discussing the interspecific relationships.

The inheritance of tetraploid wheat seed peroxidases

Embryo and endosperm peroxidases from dry mature seeds of three subspecies of tetraploid wheat (Triticum turgidum L.) were subjected to genetic analysis. The inheritance of eight isozymes (embryo isozymes a2, d1, d2, e and f; and endosperm isozymes b, d and 4) were studied in F2's obtained from different wheat accessions. Simple monogenic inheritance producing three banded: one null segregation and two epistatic segregations (9∶7 and 15∶1) were found. In the case of isozymes b, d and 4, monogenic or epistatic segregation depended on the F2 analyzed. Segregation data indicated that at least 9 different loci would determine the peroxidase isozymes of tetraploid wheat seed, all the loci studied containing 'null' alleles. Furthermore, several loci determining embryo peroxidases were noticed to be mutually linked. All these data are discussed in context of the inheritance of seed peroxidases in hexaploid wheat and rye.

Chromosomal location of isozyme markers in wheat-barley addition lines

The peroxidase (CPX, PER), α-amylase (α-AMY), acid and alkaline phosphatase (PHE, PHS) and esterase (EST) zymogram phenotypes of 'Chinese Spring' wheat, 'Betzes' barley and a number of presumptive 'Betzes' chromosome additions to 'Chinese Spring' were determined. It was found that five disomic chromosome addition lines could be distinguished from one another and from the other two possible lines on the basis of the zymogram phenotypes of these isozymes. The structural genes Cpxe-H1 and Cpxe-H2 were located in 'Betzes' chromosome 1, the Perl-H5 and Perl-H6 in chromosome 2, the α-Amy-H2 and α-Amy-H3 in chromosome 7, the Phs-H5 and Phs-H4 in chromosomes 1 and 3 respectively, the Phe-H2, Phe-H3 and Phe-H4 in chromosome 1, the Phe-H1 in chromosome 3, the Ests-H4, Este-H2 and Ests-H6, Este-H8 in chromosomes 1 and 3 respectively and the Estl-H10 and Estl-H2 structural genes were related to chromosomes 3 and 6 respectively. These gene locations provide evidence of homoeology between 'Betzes' chromosomes 1, 2, 3, 6 and 7 and the rye chromosomes 7, 2, 3, 6 and 5, respectively, and also between 'Betzes' chromosomes 1, 2, 3, 6 and 7 and the 'Chinese Spring' homoeologous groups 7, 2, 3, 6 and 5, respectively.

Phosphogluco mutase - a biochemical marker for group 4 chromosomes in the Triticinae

Structural genes for the isozymes of phosphogluco mutase (PGM) (EC 2.7.5.1) have been located on chromosome arms 4Aα, 4BL and 4DS of hexaploid wheat. These results support the homoeologies observed among these chromosome arms and also support the notion of conservation of gene synteny groups within the Triticinae.