Publication Date
1989
Description
The primary reason for producing trisomic red clover is for gene mapping. Although the methodology for producing trisomics has long been established, little research has been conducted in red clover (Trifolium pratense L.). Likewise, very few gene mapping investigations except for some early data by Williams (1937) have been reported. The program at the University of Kentucky that suggested the possibility of using trisomics for gene mapping was the attempted production of tetraplo'ids (2n = 4x = 28) via 2x-4x and 4x-2x crosses using gametic non-reduction. Some of these crosses produced triplo'ids (2n = 3x = 21 or 22) in a greater frequency than expected. These triploids were fertile, having pollen stainability of 71 % (Taylor and Wiseman, 1987). The objectives of the present research were to examine the fertility of red clover in crosses of various ploidies to produce a complete series of primary trisomics, to evaluate the trisomics agronomically, and to determine the transmission of the individual trisomes. The present paper deals mostly with the last two objectives. Seed set from 2x-3x, 3x-2x, and 3x-3x crosses averaged 9.4, 7.4 and 2.4 % respectively. Chromosome numbers produced were 2n = 14, 15, 16 and 21. About half of the progenies were diploid, one third trisomic and about 6 % putative double trisomics. All seven of the primary trisomics were tentatively identified. More trisomics were produced by 3x-2x crosses than by 2x-3x crosses indicating greater female than male transmission (Taylor and Chen, 1988).
Citation
Taylor, N L., "Trisomic Red Clover" (2025). IGC Proceedings (1989-2023). 68.
https://uknowledge.uky.edu/igc/1989/session3b/68
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
Trisomic Red Clover
The primary reason for producing trisomic red clover is for gene mapping. Although the methodology for producing trisomics has long been established, little research has been conducted in red clover (Trifolium pratense L.). Likewise, very few gene mapping investigations except for some early data by Williams (1937) have been reported. The program at the University of Kentucky that suggested the possibility of using trisomics for gene mapping was the attempted production of tetraplo'ids (2n = 4x = 28) via 2x-4x and 4x-2x crosses using gametic non-reduction. Some of these crosses produced triplo'ids (2n = 3x = 21 or 22) in a greater frequency than expected. These triploids were fertile, having pollen stainability of 71 % (Taylor and Wiseman, 1987). The objectives of the present research were to examine the fertility of red clover in crosses of various ploidies to produce a complete series of primary trisomics, to evaluate the trisomics agronomically, and to determine the transmission of the individual trisomes. The present paper deals mostly with the last two objectives. Seed set from 2x-3x, 3x-2x, and 3x-3x crosses averaged 9.4, 7.4 and 2.4 % respectively. Chromosome numbers produced were 2n = 14, 15, 16 and 21. About half of the progenies were diploid, one third trisomic and about 6 % putative double trisomics. All seven of the primary trisomics were tentatively identified. More trisomics were produced by 3x-2x crosses than by 2x-3x crosses indicating greater female than male transmission (Taylor and Chen, 1988).
