Diallel analysis to predict heterosis and combining ability for grain yield, yield components and bread-making quality in bread wheat (T. aestivum)

Abstract

Combining ability for grain yield, yield components, and several agronomic and qualitative traits, was studied in a seven-parent diallel cross. The 21 F1 hybrids and the seven parental cultivars were grown in replicated plot trials sown at normal seed density in three locations in the years 1992 and 1993. The effects of general combining ability (gca) were highly significant for all the traits measured with the exception of seeds per spikelet, while the specific combining ability (sca) effects were statistically significant for grain yield, plant height, heading time, for all the yield components, and for the Chopin alveographic parameters P and P/L ratio. For the majority of the traits measured gca was greater than sca. Standard heterosis (sh) for grain yield, i.e., the superiority of the hybrids over the best pure line cultivar(cv Eridano), was only 3.3%, confirming previous finding which indicate sh effects in the range of 10%. The most interesting hybrid derived from the cross Maestra x Golia revealed a yield level approaching that of the highest yielding cv Eridano but appeared more interesting because of its reduced plant height and superior bread-making quality, signifying a selling price 30% higher. It was concluded, therefore, that the first generation of hybrids, likely to appear on the market in the next few years, will be characterized by a yield potential only slightly superior to that of the best standard cvs but associated with other desirable traits, such as bread-making quality.

Relevance of Specific versus General Combining Ability in Winter Wheat

“…Nevertheless, σ 2 GCA was on average more pronounced compared to σ 2 SCA , which points to higher values of additive versus dominance effects. Our findings are in accordance with previous surveys in wheat (Borghi and Perenzin, 1994; Perenzin et al, 1998), which clearly underlines that selection based on GCA effects is promising and its application in multistage selection programs is relevant.…”

Hybrid performance and heterosis in F1 offspring of triticale (× Triticosecale Wittm.)

“…The G1 × G4 cross was the best combination among F 1 s for GS. Similar results were reported by Borghi and Perenzin (1994) and Zubair et al (1987). The Mh values for GS indicated that only the G1 × G4 cross showed highly positive significance, and the Hh values also exhibited highly positive significance in 5 crosses for GS.…”

Sprouting tolerance and falling number in South African hybrid bread wheat cultivars and their parent lines

“…The male line R2 should be discarded from the programme due to its poor sprouting tolerance and if males were subjected to strict selection, it should be possible to breed sprouting tolerant hybrids. Although no reports were found on the sprouting tolerance of hybrids, these results were in line with reports by other authors working on wheat (Bainotti et al, 2009;Borghi and Perenzin, 1994;Humphreys and Noll, 2002;Oury et al, 1995;Pickett and Galwey, 1997).…”