Comparative mapping of β-amylase activity QTLs among three barley crosses
Comparative mapping of β-amylase activity QTLs among three barley crosses
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DOI：
10.2135/cropsci2003.1043
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发表时间：
2003-05-01
期刊：
影响因子：
2.3
通讯作者：
Ullrich, SE
中科院分区：
文献类型：
--
作者：
Clancy, JA;Han, F;Ullrich, SE
β-淀粉酶（BA）是发芽大麦（Hordeum vulgare L.）中的淀粉降解酶之一。与α-淀粉酶（AA）不同，它不是在萌发开始时重新合成，而是在种子发育过程中积累。BA活性是一个重要的制麦质量参数，是糖化力（DP）的主要贡献者，沿着AA。本研究的目的是（i）测量和绘制北美大麦三个杂交组合的BA活性，（ii）比较不同杂交组合中BA的数量性状位点（QTL），以及（iii）确定BA与先前绘制的DP QTL之间的关系。利用“Steptoe”דMorex”（S/M）、“哈灵顿”× TR 306（H/T）和“哈灵顿”× Morex（H/M）杂交的F-1双单倍体作图群体的共有标记进行比较作图。BA活性分析进行了实地生长的种子从三个映射群体和父母，酶活性的频率分布相对正常，从每个映射群体。在所有三个杂交和所有七条染色体上鉴定了BA的QTL。在S/M中检测到7个QTL，而在H/T和H/M中各检测到3个QTL。正如预期的那样，BA QTL几乎总是与之前鉴定的DP QTL结合发现。对不同种质群体QTL文献的调查表明，BA和DP的许多QTL与本文所鉴定的QTL相同，也有一些独特的QTL。本研究的结果表明，鉴定与主要BA QTL密切相关的标记的好处是允许进一步的分子研究和标记辅助选择该性状。
beta-Amylase (BA) is one of the starch-degrading enzymes active in germinating barley (Hordeum vulgare L.). Unlike alpha-amylase (AA), it is not synthesized de novo at the onset of germination, but accumulates during seed development. BA activity is an important malting quality parameter and is a major contributor, along with AA, to diastatic power (DP). The objectives of this study were to (i) measure and map BA activity in three crosses of North American barleys, (ii) compare quantitative trait loci (QTLs) for BA among various crosses, and (iii) determine the relationship between BA and previously mapped DP QTLs. Comparative mapping was done by means of a consensus map with common markers from F-1 doubled haploid mapping populations from the crosses of 'Steptoe' x 'Morex' (S/M), 'Harrington' x TR306 (H/T), and Harrington x Morex (H/M). BA activity analyses were performed with field-grown seed from the three mapping populations and parents; Relatively normal frequency distributions for enzyme activity were obtained from each of the mapping populations. QTLs for BA were identified in all three crosses and on all seven chromosomes. Seven QTLs were located in S/M, the most genetically diverse cross, while only three each were found in H/T and H/M. As expected, BA QTLs were almost always found in conjunction with previously identified DP QTLs. A survey of QTL literature of populations of diverse germplasm showed many QTLs for BA and DP in common with those identified herein and some unique QTLs as well. The results, of this study suggest the benefits of identifying markers closely associated with major BA QTLs are to allow for further molecular studies and for marker assisted selection of this trait.