Simko Ivan, Hayes Ryan J, Truco Maria-Jose, Michelmore Richard W, Antonise Rudie, Massoudi Mark
1U.S. Department of Agriculture, Agricultural Research Service, U.S. Agricultural Research Station, Crop Improvement and Protection Research Unit, 1636 East Alisal Street, Salinas, CA 93905 USA.
U.S. Department of Agriculture, National Forage Seed Production Research Center, 3450 SW Campus Way, Corvallis, OR 97331 USA.
Hortic Res. 2018 Apr 1;5:21. doi: 10.1038/s41438-018-0022-5. eCollection 2018.
Fresh-cut lettuce is popular, but highly perishable product. Genetic studies of two bi-parental populations derived from crossing parents with rapid and slow rates of deterioration showed that the deterioration rate is a heritable trait (broad spectrum heritability, of 0.56-0.87). The major genetic determinant of the deterioration rate in both populations was the quantitative trait locus (QTL), , located on linkage group 4. This QTL explained 40-74% of the total phenotypic variation of the trait in the two populations. Saturating the region with single-nucleotide (SNP) markers allowed detection of six haplotypes in a set of 16 lettuce accessions with different rates of deterioration. Three of the haplotypes were always associated with very rapid rates of deterioration, while the other three haplotypes were associated with slow rates of deterioration. Two SNPs located 53 bp apart were sufficient to separate the 16 accessions into two groups with different rates of deterioration. The accuracy of markers-trait association was subsequently tested on 350 plants from seven F families that originated from crossing parents with different rates of deterioration. The of deterioration rate in these seven families ranged from 0.64 to 0.90. The SNP-based analysis accurately identified individuals with rapid, intermediate, and slow rates of deterioration in each family. Intermediate rate of deterioration was found in individuals having heterozygous alleles at , indicating an additive effect of the alleles. The assay can be used for fast, accurate, and reliable identification of deterioration rate after processing for salad.
鲜切生菜很受欢迎，但却是极易腐坏的产品。对由具有快速和缓慢变质率的亲本杂交产生的两个双亲群体进行的遗传学研究表明，变质率是一种可遗传的性状（广义遗传力为0.56 - 0.87）。两个群体中变质率的主要遗传决定因素是位于第4连锁群上的数量性状位点（QTL）。该QTL解释了两个群体中该性状总表型变异的40% - 74%。用单核苷酸（SNP）标记饱和该区域，使得在一组16个具有不同变质率的生菜种质中检测到6种单倍型。其中三种单倍型总是与非常快速的变质率相关，而其他三种单倍型与缓慢的变质率相关。两个相距53 bp的SNP足以将16个种质分为两组，其变质率不同。随后在来自七个F家族的350株植物上测试了标记 - 性状关联的准确性，这些家族源于具有不同变质率的亲本杂交。这七个家族中变质率的范围为0.64至0.90。基于SNP的分析准确地识别了每个家族中具有快速、中等和缓慢变质率的个体。在 处具有杂合等位基因的个体中发现了中等变质率，这表明等位基因具有加性效应。该测定法可用于在加工成沙拉后快速、准确和可靠地鉴定变质率。
