Genetic stability and maintenance of Raphanus sativus lines with an added Brassica rapa chromosome

• Published in: Plant breeding Vol. 122; no. 3; pp. 239 - 243
• Main Authors: Kaneko, Y., Yano, H., Bang, S. W., Matsuzawa, Y.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.06.2003; Blackwell
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Brassica rapa-Raphanus sativus- monosomic chromosome addition lines - genetic stability - chromosome transmission; Fundamental and applied biological sciences. Psychology; Genetics and breeding of economic plants; Interspecific and intergeneric hybridization, introgressions; Plant breeding: fundamental aspects and methodology; Addition line; Brassica rapa; Amphiploidy; Genetic stability; chromosome transmission; Chromosome; Introgression; Raphanus sativus; monosomic chromosome addition lines; Vegetable crop; Cruciferae; Dicotyledones; Angiospermae; Brassica rapa - Raphanus sativus; Spermatophyta
• ISSN: 0179-9541; 1439-0523
• DOI: 10.1046/j.1439-0523.2003.00849.x

The genetic stability and maintenance of Raphanus sativus‐Brassica rapa monosomic chromosome addition lines (a‐h‐types MALs, 2n = 19, BC2), developed by backcrossing the synthesized amphidiploid Raphanobrassica (Raphanus sativus × Brassica rapa, 2n = 38, RRAA) with R. sativus cv. ‘Shogoin’ (2n = 18, RR), was investigated. Transmission of the added alien chromosome through selected smaller seeds (SSS) and the inheritance of morphological traits and random amplified polymorphic DNA (RAPD)‐specific markers together with meiotic chromosome configuration and seed fertility were also investigated for three successive generations (BC3 to BC5). The distinctive traits and the RAPD‐specific markers of the eight types of MAL were substantially inherited and stably maintained throughout three generations, although a few variant plants (2n =18) resembling MALs (2n = 19) and hyperploidal plants (2n = 26 and 2n = 37) were generated in the earlier generations of BC3 and BC4 in comparison with BC5. The average transmission rates for three generations ranged from 26% for both the b‐type and the d‐type to 44% for the e‐type through SSS. On the other hand, the transmission rates through randomly selected seeds (RSS) were lower, ranging from 6.5% for the f‐type to 23.5% for the b‐type. In meiosis, more than 90% of PMCs showed the 9II +1I pairing configuration at metaphase I throughout three generations. For seed fertility, when backcrossed with the radish cv. ‘Shogoin’, the values were approximately 180% to 500% with the mode around 300% with the seed harvested from a pod increasing with the advancing generations. Genetic recombination between the radish chromosomes and the added chromosome is probably rare, suggesting that the added chromosome is mostly maintained unaltered in the background of the radish genome.