Aneuploid and other cytological tester sets in rye

Abstract

Cytological tester sets include series of aneuploids (nullisomics, monosomics, trisomics of different types, tetrasomics), series of rearranged chromosomes (translocations, inversions, duplications, deficiencies) and series of chromosomes recognizable by specific microscopically visible markers (C-or other banding, molecular markers). In rye, only a few (mainly tertiary and telocentric) monosomics and no viable nuilisomics have been found. Several sets of primary trisomics and some telocentric sets, usually not fully complete, have been developed, but few are still available for gene localization. A few tertiary trisomics have been derived from translocation heterozygotes. Extensively used are different sets of additions of rye chromosomes to wheat. A relatively widely distributed set of marked chromosomes is the Wageningen translocation tester set, complemented with translocations from different other institutions. A disadvantage of rye translocations is insufficient heterozygote semisterility. Series of otherwise rearranged chromosomes have not been reported. Sets of lines with chromosomes conspicuously differing from the standard C-banding pattern have been obtained. Molecular markers are available for most rye chromosome, but lack of heterozygosity, necessary for classification after in situ hybridization is a restriction for use as cytological testers. In the cases of most translocations, C-banding and in situ molecular markers, each separate plant in a segregating population must be screened cytologically, whereas with aneupioid markers or with translocations having sufficient heterozygote semisterility, analyzing segregations is sufficient. This article has been previously published in EuphyticaVol. 83, pp. 53-61.

Gamma Ray Induced Chromosomal Interchange in Safflower (Carthamus tinctorius L.)

“…The segregation pattern of these translocation heterozygotes has been lacking in safflower, however, due to poor staining ability and the problem of chromosome stickiness. Along with other structural chromosomal aberrations, reciprocal translocation served as an excellent cytogenetic tool for the identification and mapping of differ-ent linkage groups in plants (Sybenga 1996). It has also been involved successfully in transferring desirable traits (Sears 1956;Gustafsson 1965) and in generating different trisomics in a number of crop plants (Sutton 1939;Ramage 1960;Ashraf and Bassett 1987;Lakshmi and Nalini 1989;Auger and Birchler 2002).…”

Meiotic analysis of induced translocation heterozygotes in Lepidium sativum Linn.

“…The observed effects in the reciprocal translocation are the formation of multivalent associations at metaphase I and increased pollen, ovule sterility (Shaikh et al, 2020), and the production of aneuploids with other chromosomal aberrations. Reciprocal translocation serve as a supremacy tool for identifying and mapping different linkage groups in plants (Sybenga et al,1996;Pack et al, 1993).…”

Meiotic Investigation in Reciprocal Translocation Heterozygotes of <i>Commelina benghalensis</i> L. (Commelinaceae) Induced by Gamma Irradiations

“…Reciprocal translocations are usually identified by the presence of characteristic multivalent associations at metaphase I followed by partial pollen and ovule abortion (Khah and Verma 2020). Along with different aneuploids and other structural chromosomal aberrations, reciprocal translocation served as excellent cytogenetic tools for the identification and mapping of different linkage groups in plants (Sybenga 1996). It has also been involved successfully in transferring desirable traits (Sears 1956, Gustafsson 1965 and to generate different trisomics in a number of crop plants (Ashraf and Bassett 1987, Lakshmi and Nalini 1989, Talukdar 2009).…”