Utilization of Genetic Variability of Resynthesized Rapeseed

Abstract

The performance of single cross hybrids between resynthesized (resyn) genotypes and varieties of rapeseed was tested in microplots. The results revealed strong genetic differences between the artificially synthesized rapeseed fortns for all the characters investigated, as well as for g.c.a. values. In particular, hybrids with resyn rapeseed exhibited a vigorous vegetative growth. It should, therefore, be beneficial to use resyn forms directly in fodder rape breeding programmes.Disturbances in fertility of the resyn material resulted in a low number of seeds per pod and consequent!)' in an inferior seed yield as compared to the varieties, although some high yielding combinations were also identified. Three-way hybrids with a 25 % genome share of the resyn rapeseed reached only lower vegetative performance as compared to the hybrids with a 50 % resyn genome but their performance in generative traits was generally superior. In respect to seed yield some progenies of three-way hybrids showed a higher plot performance than even the high yielding varieties. A further comparison between smgle-cross combinations of resyn X variety on the one hand and variety x variety on the other hand demonstrated th,at resyn genotypes, due to a distinct apical dominance, exhibited a pronounced expression of characters measured on the main stem. But in total, it is evident from the present findings that any hybridization with this resyn material does not promise immediate shortterm varietal improvement.

Physiological Constraints and Their Genetic Manipulation

“…Resynthesized B. napus genotypes have been used in extensive genetic studies (Krliling 1987). General combining ability estimates were negative for most growth and yield component characters in some of the resynthesized genotypes, but others had high positive values for seed yield per plant, dry matter at anthesis and pods per main stem.…”

Introgression of genes into cultivated Brassica napus through resynthesis of B. napus via ovule culture and the accompanying change in fatty acid composition

“…The release of the oilseed cultivar`Norde' in Sweden (Olsson and Ellerstrom 1980) demonstrated how successful an appropriate introduction of resynthesized rapeseed can be in breeding programmes. Resynthesized B. napus provides not only various gene sources from B. campestris and B. oleracea but also potential germplasm for heterosis utilization in rapeseed breeding (KraÈ ling 1987).…”

Stand und Perspektiven der Züchtung von Raps (Brassica napus L.) mit hohem Erucasäure‐Gehalt im Öl für industrielle Nutzungszwecke

“…Genotyp 'Synra' (08) 'Marcus' (1 1) 'Bridger' (43) 'Bridger' (44) 'Bridger' (45) KO3 (08 x 11) K12 (11 x 08) …”