Potential of rutabaga (Brassica napus var. napobrassica) gene pool for use in the breeding of hybrid spring Brassica napus canola

The use of rutabaga for increasing the level of heterosis in spring canola was investigated. For this, test hybrids were produced by crossing four inbred populations, derived from F2 and BC1 of two rutabaga × spring canola crosses, to their spring canola parent, and were tested in field‐plots for agronomic and seed quality traits. Average mid‐parent heterosis (MPH) in these test hybrid populations was about 5%‐15% for yield. Compared to the F2‐derived population, the BC1‐derived population exhibited 1.8‐times greater MPH for yield. No correlation was found between inbred and test hybrid for yield; however, a positive correlation of genetic diversity of the inbred lines was found with MPH (r = .58) and hybrid yield (r = .36) suggesting that non‐additive effect of the genes may play an important role for high yield in hybrids. About 2% negative MPH was found for days to flowering, while almost no heterosis was found for seed oil and protein contents. Thus, our study demonstrates the potential of the rutabaga gene pool for use in hybrid canola breeding.