The effects on barley starch and grain properties of four starch synthesis mutations were studied during the introgression of the mutations from diverse backgrounds into an elite variety. The lys5f (ADPglucose transporter), wax (granule-bound starch synthase), isa1 (debranching enzyme isoamylase 1) and sex6 (starch synthase IIa) mutations were introgressed into NFC Tipple to give mutant and wild-type BC2F4 families with different genomic contributions of the donor parent. Comparison of starch and grain properties between the donor parents, the BC2F4 families and NFC Tipple allowed the effects of the mutations to be distinguished from genetic background effects. The wax and sex6 mutations had marked effects on starch properties regardless of genetic background. The sex6 mutation conditioned low grain weight and starch content, but the wax mutation did not. The lys5 mutation conditioned low grain weight and starch content, but exceptionally high β-glucan contents. The isa1 mutation promotes synthesis of soluble α-glucan (phytoglycogen). Its introgression into NFC Tipple increased grain weight and total α-glucan content relative to the donor parent, but reduced the ratio of phytoglycogen to starch. This study shows that introgression of mutations into a common, commercial background provides new insights that could not be gained from the donor parent.

中文翻译：

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使用先进的重组系研究影响大麦淀粉合成的突变的影响和潜力

研究了四种淀粉合成突变对大麦淀粉和谷物特性的影响，这些突变是在从不同背景的突变渗入到优良品种的过程中进行的。lys5f（ADP 葡萄糖转运蛋白）、wax（颗粒结合的淀粉合酶）、isa1（脱支酶异淀粉酶 1）和 sex6（淀粉合酶 IIa）突变被渗入 NFC Tipple，以产生具有不同基因组贡献的突变型和野生型 BC2F4 家族捐赠者父母。比较供体亲本、BC2F4 家族和 NFC Tipple 之间的淀粉和谷物特性，可以将突变的影响与遗传背景影响区分开来。无论遗传背景如何，蜡和 sex6 突变对淀粉特性都有显着影响。sex6 突变以低粒重和淀粉含量为条件，但蜡突变没有。lys5 突变导致粒重和淀粉含量低，但β-葡聚糖含量异常高。isa1 突变促进可溶性α-葡聚糖（植物糖原）的合成。相对于供体亲本，其渗入 NFC Tipple 增加了粒重和总 α-葡聚糖含量，但降低了植物糖原与淀粉的比例。这项研究表明，突变渗入到共同的商业背景中提供了无法从供体父母那里获得的新见解。但降低了植物糖原与淀粉的比例。这项研究表明，突变渗入到共同的商业背景中提供了无法从供体父母那里获得的新见解。但降低了植物糖原与淀粉的比例。这项研究表明，突变渗入到共同的商业背景中提供了无法从供体父母那里获得的新见解。