Abstract

When seedlings from a partial 8 X 8 diallel were propagated and grown at Auchincruive (west Scotland) and at Invergowrie (east Scotland) in order to identify parents which transmit stability for yield and its components and to identify genotypes prone to barrenness, Gorella, Cambridge Favourite and 53Q13 transmitted most vigour whilst 60CE5 gave largest numbers of crowns. Site had a major effect on inflorescences per crown, there being 30% less at Invergowrie than at Auchincruive. Parents most closely related to wild species, 53Q13, 60CE5 and Cambridge Favourite, were the most prepotent for high inflorescence number per crown. Crosses involving Cambridge Favourite and 53Q13 were the most stable whilst those involving Redgauntlet and Talisman were least stable. Low inflorescence number per crown at Invergowrie was partially compensated for by greater numbers of fruits per inflorescence. Site had a minor effect on fruit size. Gorella, Redgauntlet and Talisman progenies gave the largest fruit and 53Q13 the smallest. Close association between stability and inflorescence production simplified selection for stability and, because the effects of site and general combining ability were so much more important than their interactions, selection at either site for adequate inflorescence numbers should ensure stability.