油菜油脂研究进展

油菜(Brassica napus)是世界范围内重要的油料作物, 是植物油脂的第三大来源, 其种植面积和总产量在油料作物中占有相当大的比例。我国油菜品种油脂含量普遍较国外低2-5个百分点, 而油脂含量每增加1个百分点对产油量提高的贡献, 相当于菜籽产量提高2.5个百分点。因此提高油菜油脂含量是解决油菜生产效益低的重要途径之一。本文综述了油菜油脂研究的状况, 包括油脂积累的遗传学基础、油脂合成途径和调控、油脂含量的QTL定位及油脂含量与品质性状的遗传相关性, 同时展望了油菜油脂研究前景, 以期为油菜油脂含量的品种改良提供科学指导。     

BnFAD2、BnFAD3和BnFATB基因的共干扰对油菜种子脂肪酸组分的影响

甘蓝型油菜是一种重要的油料作物,为了改良其种子脂肪酸组分,提升其经济价值,本研究分析了油菜种子发育时期脂肪酸合成积累模式及BnFAD2、BnFAD3、BnFATB基因的表达规律,认为这3个基因在种子发育中后期(授粉后25d起)的高效表达对油酸合成积累有着重要影响。通过Napin启动子诱导对油菜植株中BnFAD2、BnFAD3、BnFATB基因进行RNAi共干扰抑制,以达到提升油酸含量的目的。试验结果表明,转基因油菜种子中BnFAD2、BnFAD3、BnFATB基因的表达受到强烈抑制,种子中油酸含量由66.76%提升至82.98%,且油脂合成的相关基因同步出现表达上调。     

优质油菜籽粕蛋白质分类研究

油菜是我国大面积种植的油料作物 ,油菜籽富含油脂和蛋白质。其含硫氨基酸含量高于大豆蛋白 ,必需氨基酸含量平衡[1 ] ,因此菜籽蛋白有良好的营养特性。但常规油菜籽饼粕含较高的硫代葡萄糖甙和酚类物质 ,长期以来籽粕蛋白没有被利用作饲料或食品添加剂。我们用双低 [2 ] (低芥酸、低硫甙 )优质油菜饼粕为材料 ,根据其蛋白在不同溶剂的溶解性分离 [3] ,测定了不同组分蛋白及其含量 ,并对各组分蛋白氨基酸含量也进行了测定 ,为说明优质油菜饼粕蛋白富含各种必需氨基酸和其良好的开发前景提供了依据。1 　实验材料及方法1 .1 　材料中双 1 1 9…     

薄层色谱法分离植物种子中主要不饱和脂肪酸的研究

测定植物种子中主要不饱和脂肪酸,在油脂品质鉴定、营养研究、油料作物品种选育(特别是油菜)以及发掘新的有价值的油料植物资源等方面,都有重要意义。现在检测菜籽油芥酸含量的方法有:气相色谱法、纸色谱法、冷冻法、分步沉淀法和混浊法。用于分离较长链不饱和脂肪酸的方法除了气相色谱     

利用叶绿素荧光快速筛选紫外诱变高含油小球藻

本实验利用尼罗红荧光与叶绿素荧光比值表征小球藻的油脂含量,快速筛选出一株紫外诱变高产油藻株。经过叶绿素荧光分析表明,诱变株M2的生长及光合作用没有显著变化。检测诱变株M2总油脂含量32.1%,比野生藻株的23.1%提高了9个百分点。     

不同甘蓝型油菜高含油量种质资源的脂肪酸成分分析

甘蓝型油菜是我国最为重要的油料作物之一.目前我国面临着植物油严重不足的局面.提高含油量是目前甘蓝型油菜育种的主要方向之一.目前.我国育种工作者已经筛选出了大量含油量超过50%的甘蓝型油菜种质.本文对两种类型的高含油量甘蓝型油菜种质进行了脂肪酸组分分析,结果显示芥酸含量高的种质和芥酸含量低的种质的脂肪酸在菜籽油中变化范围和平均值明显不同.油酸和亚油酸在低芥酸高含油量甘蓝型油菜种质中的含量较高,约占整个油分的80%左右,其他脂肪酸组分则在10%以下;而芥酸则是高芥酸高含油量种质的最主要的成分,约占整个油分的44%左右,油酸、亚油酸等的含量则均在10%左右.相关性分析表明:芥酸和其他脂肪酸之间呈现显著负相关,因此.可以通过降低高芥酸油菜种质中的芥酸含量来提高比如油酸和亚油酸的含量.从而使这些种质的油分更适合人类的健康.     

转vgb基因油菜的耐涝性

油菜是我国重要的油料作物和蛋白质饲料作物,涝害严重影响了我国油菜产业的发展,提高油菜的耐涝能力对于我国油菜可持续发展具有非常重大的意义。本研究采用PCR、Southern杂交等方法对转vgb基因油菜植株进行鉴定,15 d淹涝实验结果显示,转基因油菜的超氧化物歧化酶、丙二醛和脯氨酸含量在淹涝前后的变幅显著低于对照。对淹水后的农艺性状进行调查,转vgb基因的油菜相比较对照抗涝性明显得到增强,证明vgb基因在油菜中的表达对油菜的抗涝性具有显著作用。     

植物脂肪酸代谢途径遗传调控的研究进展

目前,利用传统育种方法改良油料作物脂肪酸组分已取得巨大成功,通过有性杂交、X-射线或EMS处理等方法都可用来修饰存在于油菜中脂肪酸的性质。国外已培育出高棕榈酸、高或低亚油酸、高油酸和无芥酸的油菜品种。但由于油料作物基因池(Gene Pool)的局限性使得育种学家不得不寻找其他种质资源。随着基因克隆和遗传转化技术的进步,通过基因工程改良油料作物品质已成可能。本文主要介绍了植物脂肪酸的代谢途径以及通过操纵TAG的生物合成来改变油的成分等研究,其中主要包括脂肪酸链长度的改良、饱和度改良、增加脂肪酸含量以及新的不饱和脂肪酸的改良等方面。不久的将来,转基因油料作物中将会产生更有价值的脂肪酸造福于人类。     

油菜矮秆相关基因定位克隆及其在育种中的应用

油菜是世界主要油料作物。倒伏问题是制约油菜机械化生产和产量提高的重要因素之一。矮秆油菜抗倒伏,有利于提高产量。因此,选育矮秆资源对油菜抗倒和高产育种具有重要意义。近年来,相关研究报道了多个具有育种价值的油菜矮秆材料,定位克隆了矮秆性状相关基因。本文就油菜矮秆相关基因定位克隆及其在育种中的应用研究进展进行综述,以期为发掘新的油菜矮秆基因以及油菜抗倒高产分子设计育种提供参考。     

低场核磁共振技术快速检测小球藻油脂含量及其在高通量选育中的应用

为了建立一个高效的高产油微藻诱变育种流程,微藻中油脂含量快速和准确的测定在其中具有重要作用。在本研究中,首先利用低场核磁共振技术,建立了直接检测干藻粉和培养液中小球藻油脂含量的方法,其信号强度与细胞中油脂含量存在特异的线性关系,干藻粉和藻液中油脂含量与信号值拟合的R2均高于0.99,说明该方法用于小球藻油脂含量的检测是准确和可行的。同时该方法与传统油脂测量方法相比,具有快速、简便和准确等优点。但其通量不及尼罗红染色法,因此,我们开发了将尼罗红染色法用于初筛,低场核磁共振技术用于复筛的新型高通量藻种复合筛选方法,并将此筛选方法应用于一种异养高产油原壳小球藻的诱变育种过程中。首先从3 098株诱变藻种中初筛得到108株具有较高油脂含量的藻株,然后利用低场核磁共振技术复筛得到9株高产油性能的藻株,其中一株甘油三酯含量超过20%,比原始藻株提高1倍,培养168 h后培养液油脂浓度达到5 g/L,证明此诱变育种流程不仅提高了筛选的效率还可靠且可行。     

高油酸油菜遗传育种研究进展

油酸（C18∶1）是双低菜籽油的主要脂肪酸之一,合理的高油酸菜籽油脂肪酸组分更有利于人体健康,因此提高油酸含量是双低油菜品质育种的一个重要方向。当前我国高油酸油菜品种选育相关研究进展缓慢,高油酸菜籽油产业化进程急需提速。围绕高油酸油菜主要从四个方面开展论述：国内外利用理化方法成功创建的油菜高油酸种质资源及其高油酸性状遗传模式;油菜高油酸性状的控制基因及其突变位点;世界上高油酸品种的培育以及我国高油酸品种的发展趋势;当前高油酸品种的不足及今后高油酸油菜品种的改良途径。为油菜育种工作者较全面地展示了国际上高油酸油菜在遗传育种方面的研究成果,也为今后我国高油酸油菜的进一步发展提供了参考。     

1982-2012年江苏省审定油菜品种系谱及性状分析

分析了1982-2012年江苏省审定的62个油菜品种的亲本系谱、品种特性以及主要农艺性状和经济性状特点。结果表明,江苏省审定的甘蓝型油菜品种的原始亲本为胜利油菜,低芥酸性状主要源自Zephyr、Primor、Midas和荣山等,低硫苷性状主要源自Tower、Wesroona、Marnoo和Wesbrook等。江苏省审定的油菜品种的主要农艺性状中,生育期逐步缩短,并基本稳定在243 d左右;株高变化较大,因品种而异。4个产量(产油量)构成因素中,含油量年平均增幅最大,尤其是在2003-2012年间,年平均增幅达到0.65%;单株角果数和每角粒数有上升趋势,而千粒重则变化相对较小。受双低性状对产量性状的负效应影响,产量及产油量在1982-2012年间的年平均增幅均不大,但优质常规品种的产量与产油量的年平均增幅较大,分别为23.10 kg/hm2和13.20 kg/hm2。研究结果可为江苏省油菜新品种的选育与推广提供参考。     

油菜高含油量基因工程研究

油菜是世界上重要油料作物之一,是世界食用植物油的重要来源。近十年来,随着其种植面积的不断扩大,目前已成为世界第二大植物油来源,因此提高油菜种子含油量具有重大的经济利用价值。近年来,基因工程技术的飞速发展带来了优化油菜品种资源的新方法。三酰甘油对种子油脂的形成十分重要,它是油菜种子最主要的储藏脂类。将三酰甘油合成代谢途径中的关键酶基因及一些转录因子转入到油菜组基因中,一方面增加种子中关键酶基因的表达;另一方面增加转录因子表达以增强糖酵解和三酰甘油形成的相关基因表达,增加底物浓度和三酰甘油合成的速度,期待获得高含油量的转基因油菜。本文综述了国内外关于油菜油酯代谢关键酶基因及调控基因的研究进展,并展望了未来提高油菜含油量的发展思路。     

Effect of inter- and intragenic epistasis on the heritability of oil content in rapeseed (Brassica napus L.)

The loci detected by association mapping which are involved in the expression of important agronomic traits in crops often explain only a small proportion of the total genotypic variance. Here, 17 SNPs derived from 9 candidate genes from the triacylglycerol biosynthetic pathway were studied in an association analysis in a population of 685 diverse elite rapeseed inbred lines. The 685 lines were evaluated for oil content, as well as for glucosinolates, yield, and thousand-kernel weight in field trials at 4 locations. We detected main effects for most of the studied genes illustrating that genetic diversity for oil content can be exploited by the selection of favorable alleles. In addition to main effects, both intergenic and intragenic epistasis was detected that contributes to a considerable amount to the genotypic variance observed for oil content. The proportion of explained genotypic variance was doubled when in addition to main effects epistasis was considered. Therefore, a knowledge-based improvement of oil content in rapeseed should also take such favorable epistatic interactions into account. Our results suggest, that the observed high contribution of epistasis may to some extent explain the missing heritability in genome-wide association studies.     

甘蓝型特高含油量油菜种质资源及主栽品种指纹图谱构建

本研究选择特高含油量资源7份,与中国各油菜主产区具有代表性的主栽品种16份,利用SSR多引物组合法开展指纹图谱构建研究。选择多态丰富、图谱清晰稳定且来自不同连锁群的引物28对,对所有材料进行指纹图谱分析,共获SSR指纹条带302条,其中多态性条带为279条,每引物所获条带6-16条,平均10.79条,平均多态率92. 38%,通过指纹图谱将所有材料有效地区别开来。用非加权类平均法（UPGAM）聚类分析显示：高油材料之间以及高油材料与主栽品种之间遗传距离均有较大差异,在遗传距离0.171处可将23份材料分成9个类群,其中7份高油材料分处4个类群,遗传距离差异显著;而其他8份主栽品种被分别聚类在另外5个类群中;所有材料间皆具有丰富的遗传多样性,其中高油材料与主栽品种间遗传差异更大。     

Heterotic patterns in rapeseed (<Emphasis Type="Italic">Brassica napus</Emphasis> L.): I. Crosses between spring and Chinese semi-winter lines

Chinese semi-winter rapeseed is genetically diverse from Canadian and European spring rapeseed. This study was conducted to evaluate the potential of semi-winter rapeseed for spring rapeseed hybrid breeding, to assess the genetic effects involved, and to estimate the correlation of parental genetic distance (GD) with hybrid performance, heterosis, general combining ability (GCA) and specific combining ability (SCA) in crosses between spring and semi-winter rapeseed lines. Four spring male sterile lines from Germany and Canada as testers were crossed with 13 Chinese semi-winter rapeseed lines to develop 52 hybrids, which were evaluated together with their parents and commercial hybrids for seed yield and oil content in three sets of field trials with 8 environments in Canada and Europe. The Chinese parental lines were not adapted to local environmental conditions as demonstrated by poor seed yields per se. However, the hybrids between the Chinese parents and the adapted spring rapeseed lines exhibited high heterosis for seed yield. The average mid-parent heterosis was 15% and ca. 50% of the hybrids were superior to the respective hybrid control across three sets of field trials. Additive gene effects mainly contributed to hybrid performance since the mean squares of GCA were higher as compared to SCA. The correlation between parental GD and hybrid performance and heterosis was found to be low whereas the correlation between GCA_{(f + m)} and hybrid performance was high and significant in each set of field trials, with an average of r = 0.87 for seed yield and r = 0.89 for oil content, indicating that hybrid performance can be predicted by GCA_{(f + m)}. These results demonstrate that Chinese semi-winter rapeseed germplasm has a great potential to increase seed yield in spring rapeseed hybrid breeding programs in Canada and Europe.     

Effects of Heat Stress during Seed Filling Stage on <i>Brassica napus</i> Seed Oil Accumulation and Chlorophyll Fluorescence Characteristics

As global temperature rise, the threat of heat stress to rapeseed production is becoming more obvious. Exploring the response characteristics of two important biological pathways, oil accumulation and photosynthesis, to heat stress during B. napus seed filling is helpful in the genetic improvement of heat-tolerant rapeseed. The effects of heat stress on seed oil accumulation and chlorophyll fluorescence characteristics of 29 B. napus germplasms with different oil content and environmental sensitivity, including 6 rapeseed varieties which exhibited environment-sensitive/insensitive and with high, medium or low oil content, were tested by whole plant heat stress or the in vitro silique culture system. Both assay exhibited similar trend on oil content of the rapeseed germplasms. The heat effect on the chlorophyll fluorescence kinetic parameters F_v/F_m, ETR and Y(II) were also consistent. Heat stress significantly decreased oil content, although there was abundant genetic variation on heat tolerance among the genotypes. Correlation analysis showed that the decrease rate of F_v/F_m of silique heat-stressed B. napus developing seed was positive correlative to the decrease rate of mature seed oil content of the whole plant heat-stressed rapeseed (R = 0.9214, P-value < 0.01). Overall, the results indicated that heat stress inhibited oil accumulation and photosynthesis in B. napus developing seed. The decrease rate of chlorophyll fluorescence parameter F_v/F_m of heat-stressed developing seed could be used as the index of heat tolerant rapeseed identification. Further, two heat insensitive rapeseed varieties with high oil content were identified.