摘要： 为拓宽新的紫色材料资源，选育出属于中国的紫色大白菜品种，以新型紫色材料15NG28及其杂交F₁、回交一代BC₁F₁、自交后代等为材料，研究其植物学性状、叶片的花青苷分布、基因组倍性和染色体数、基于转录组测序的差异表达基因等。结果表明，紫色材料15NG28与大白菜可以进行常规杂交，并获得F₁种子，F₁植株叶片颜色表现为紫色和绿色2类。在幼苗期和成株期，15NG28与紫色F₁植株子叶和真叶的正反面、叶脉均表现为紫色，紫色F₁叶柄正反面也表现为深紫色，但15NG28叶柄的正面为紫色，反面为绿色。同时，F₁植株的基因组倍性和染色体数也不同，倍性表现为3n、4n和6n等，染色体数为24，28，36条等。其中16M-170-21叶片性状偏向于芥菜型，自交结实性好，自交后代植株表现出差异明显的性状，而16M-170-22叶片性状偏向于白菜型，在其BC₁F₁中31株全部表现为白菜性状，紫色与绿色植株的分离比例为14：17，且14株紫色植株的自交结实性状好。紫色与绿色植株转录组测序结果表明，紫色植株的类黄酮、黄酮、黄酮醇和花青素合成途径的12个基因表达量均明显上调，其中2个结构基因无色花青素双加氧酶Bra013652（LDOX）和二氢黄酮醇还原酶Bra027457（DFR）表达量在紫色植株中最高，该结论不同于在紫色白菜中已报道的R2R3-MYB转录因子c3563g1i2。因此，初步认为15NG28及其后代可能为新的紫色大白菜资源，15NG28可能来源于芥菜。

关键词: 大白菜, 紫色资源15NG28, 转录组测序, 结构基因, 育种

Abstract: In order to expand the new purple material resources and breed our own purple Chinese cabbage varieties in China,we focused on a new purple germplasm 15NG28,its F₁ back-crossing F₁ and self-bred progenies to study characteristics,distribution of anthocyanins in leaf,ploidy modes in genome,chromosome patterns and differentially expressed genes of these progenies.Results showed F₁ hybrids crossed by 15NG28 and Chinese cabbage could be obtained,which segregated purple and green colors.At the seedling and adult stages,15NG28 and purple F₁ plants had purple colors in adaxial leaf,abaxial leaf,vein,while the F₁ plants owned purple colors in adaxial,abaxial blade of leaf and 15NG28 had purple color in adaxial blade,green color in abaxial blade.Meanwhile purple F₁ hybrids had different ploidy modes,i.e.,3n,4n,6n,etc.and chromosome patterns,i.e.,24,28,36,etc.Among them,16M-170-21 was similar as B.juncea.16M-170-21 self-bred seeds could be gotten,which showed distinctly different characteristics.While 16M-170-22 was similar as Chinese cabbage.Characteristic of 31 BC₁F₁ progenies of 16M-170-22 were the same as Chinese cabbages,and purple to green ratio was 14:17.Especially self-bred seeds of 14 purple lines were better.RNA-seq results showed twelve genes involved in flavonoid,flavone,flavonol and anthocyanin biosynthesis pathway were apparently up-regulated in purple lines.Interestingly Bra013652 (as LDOX gene) and Bra027457 (as DFR gene) were structural genes,which were up-regulated apparently in purple lines compared to green lines.Especially the two genes were differently from c3563g1i2,a regulator factor R2R3-MYB reported before.Therefore 15NG28 and its progenies could be new germplasm resources and 15NG28 might origin from B.juncea.

Key words: Chinese cabbage, Purple leaf germplasm 15NG28, RNA-seq, Functional genes, Breeding

中图分类号: 

• Q78

• S634.03