利用人工合成六倍体小麦突破小麦产量瓶颈的机会与潜力

 以人工合成小麦Syn CD780及其衍生品种川麦42与优良栽培品种杂交构建的2个重组近交系群体为材料，进行多环境（年份×地点）田间试验和产量性状QTL分析，探讨利用人工合成小麦资源突破小麦产量瓶颈的机会与潜力。结果表明：① 所考察性状均呈连续性变异和双向超亲分离。S12群体（Syn CD780×川育12）高产株系平均单产670 t/hm2，比川育12提高64%，增产缘于千粒质量的显著提高（100%）；S16群体（川麦42×川农16）高产株系平均单产79 t/hm2，比川农16增产181%，增产缘于粒数/m2和千粒质量的共同提高。② 基于S16群体实验数据，共检测到LOD＞30的产量性状QTLs 55个。其中，产量QTLs 7个，贡献率75%~273%，均来自CM42；产量构成因素QTLs 48个，贡献率78%~328%。利用人工合成小麦或其衍生品种突破四川盆地小麦产量瓶颈的潜力较大。 

Opportunities for Breaking the Barriers of Wheat Yield Using Synthetic Hexaploid Wheats

To probe into the opportunities for breaking the barriers of wheat yield using synthetic hexaploid wheat (SHW), two sets of recombinant inbred lines (RILs), S12 (Syn CD780×Chuanyu12, 131 lines) and S16 (SHW derived variety Chuanmai42×Chuannong16, 127 lines), were planted in multi environments (year×site) in 2006-2008. Phenotypic data were collected for fifteen agronomic traits of both S12 and S16 and 280 microsatellite markers were employed to genotype lines of S16. Continuous variation and transgressive segregation for all tested traits were observed. Grain yield of superior lines in S12 was 64% higher than Chuanyu12 achieved by increasing kernel weight (≈ 10%). Average grain yield of the top ten high yielding lines in S16 was up to 79 t/hm2, 181% higher than Chuannong16 by increasing both kernel weight and grains m-2. Using single marker regression and interval mapping, a total of 55 putative QTLs with a LOD score ＞30 based on S16 were detected, of which 7 were for grain yield, 40 for yield components, and 8 for rates of grain and biomass production. For 38 (691%) of them, alleles from the SHW derived variety Chuanmai42 were associated with a positive effect on yield related traits. The present studies indicated that breaking barriers of wheat yield using SHW is feasible.