Relationship Among Yield Components and Selection Criteria for Yield Improvement in Early Rapeseed (Brassica napus L.)

The objective of this study was to determine the relationship between seed yield and other important agronomic traits of early-maturing rapeseed as a rotation crop in a double-cropping rice area using Pearson＇s correlation coefficient as well as to estimate direct and indirect effects of specific yield component traits on seed yield via path analysis. Nineteen rapeseed genotypes were grown at ten environments in South China during 2008-2009 and 12 characters were evaluated. Analysis of variance showed that environment had a significant impact on all characters. For most characters the genotype by environment interaction was weak and not statistically significant. Simple correlation analysis indicated that the number of primary branches （PB）, number of pods on the main raceme （PR）, and number of seeds per pod made significant contributions to seed yield per plant （SYP）, while 1 000-seed weight was negatively correlated with SYP （r=-0.485, P0.05）. Furthermore, number of pods per plant （PP）, PB, and PR had the greatest direct effects on SYP. In addition, PP and PB were the best indicators to predict seed yield in stepwise regression analysis. Finally, yield component differences between early- and medium-maturity varieties were compared; this showed that to improve the seed yield of early varieties, more emphasis should be given to increase PP, PB, and PR, and reduce plant height and shortening of growth duration in breeding practice.

Comparions of Required Nitrogen Fertilizers by Hybrid Cultivar and Conventional Cultivar of Rapeseed(Brassica napus L.)

[Objective] The aim of this study was to understand the difference of N fertilizer requirement between hybrid rapeseed and conventional rapeseed. [Method] Two hybrid cultivars, ZY5628 and ZY7819, and the conventional cultivar ZS10, were compared through two field experiments. In Experiment 1, seed yield and optimum N application rate were assessed in the field with five N application treatments. In Expedment 2, N was applied uniformly at 180 kg/hm2, and plant biomass and N accumulation were measured at several developmental stages, while N use efficien- cy was calculated for rape at maturity. [Results] The experiment 1 results showed that seed yields of ZY5628 and ZY7819 were both significantly higher than that of ZS10, and compared to ZS10, optimum yield （plateau yield） was higher by 18.7% and 20.2%, while the recommended N application rate was lower by 9.5% and 9.6% for ZY5628 and ZY7819, respectively. The experiment 2 results showed that during vegetative development, all three cultivars exhibited similar accumulations of plant biomass and N, but through flowering and maturity ZY5628 and ZY7819 pro- duced more biomass, acquired more N, and utilized acquired N more efficiently to- wards seed production than ZS10. [Conclusion] With equivalent inputs, the hybrid rapeseed cultivars ZY5628 and ZY7819 tested herein yield more seed with higher N use efficiency than the conventional rapeseed ZS10. This information will be valu- able for growers seeking to improve efficiency while reducing costs of rape production in China.

Recent Advances,Problems and Outlooks in Rapeseed(Brassica napus L.)Breeding in China

As a big rapeseed （Brassica napus L.） producing and consuming country, China provides more and more rapeseea oil year by year. With the development of demand for rapeseed and import of edible oil, rapeseed breeding and production is fac- ing a great challenge. New situation has proposed higher requirements to yield, oil quality and safety, etc. In the review, some aspects about rapeseed breeding in China were reported, including breeding of high-oil content rapeseed, breeding of extremely early-maturing rapeseed, development of mechanization and development of chemical emasculation. Some prospects and expec- tations were also proposed.

Brassinosteroids promote seed development and physiological maturity of oilseed rape (Brassica napus L.)

Long developmental stage and late harvest time of winter rapeseed (Brassica napus L.) have great negative effects on rice planting of rice-rapeseed farming system in China. Early maturity improvement of rapeseed is necessary. ‘Zhongshuang 11’, an elite winter rapeseed cultivar, was used in consecutive field experiments during 2010-2012. At initial flowering stage, plants were consecutively sprayed with 0.1 mg/L 2-4-Epibrassinolide(BR) for 3 d. Two hundred sampling pods from different plants were randomly collected to measure seed related indexes with a 4 d interval from 7 to 47 d after peak anthesis (DAPA).Seed color turned light brown at 31 or 35 DAPA after BR treatment, seed dry weight (DWT)was increased while seed moisture content (SMC) was decreased during seed development.DWT almost reached the maximum value when SMC was 33.20% at 31 DAPA in 2010-2011 and 35.29% at 35 DAPA in 2011-2012 growing season after BR treatment. Similarly,the maximum values of standard germination test (SGT), accelerated aging test (AAT)and cold test (CT) were observed at 31 or 35 DAPA after BR treatment respectively. The high yield and seed oil content appeared at 31 or 35 DAPA accompanied with rapid decrease in total non-structural carbohydrate (TNC) in stems and leaves. Our study indicated that BR application advanced maturity of winter rapeseed by 4 to 8 days.

Effects of non-procedural factors in Brassica napus genetic transformation

Rapeseed (Brassica napus) is the second largest oil crop in the world. However, transformation efficiency of rapeseed still needs to be improved. To evaluate non-procedural factors (e.g. explants, section of explant, marker genes and number of exogenous genes) effects on transformation efficiency, 6-day-old hypocotyl explants from in vitro grown seedlings were co-cultivated with Agrobacterium strain GV3101 harboring a binary vector using optimized transformation procedure. Results showed that normal maturing variety ‘Zhongshuang 6 (ZS6)’ had the highest overall capacity to produce rooted shoots among 5 common varieties and 6 early maturing varieties, with green callus induction rate 81.45% and shoot regeneration rate 21.66%. Early maturing variety 14M645 has relatively high regeneration rate (4.69%) and one of the shortest growth periods (107.54 d). Data showed that choosing neomycin phosphotransferase II gene (NPTII) as selectable marker led to the best transformation rate (17.38%). Selecting upper hypocotyl segments near cotyledon as explant provided the higest transformation efficiency, with regeneration rate of 25.59% when using NPTII as selectable marker and 22.19% for Bar. B. napus transformed with single gene showed higher transformation frequency than vectors with multiple genes,highlighting difficulty of multiple gene transformation. This work helped to further improve genetic transformation of B. napus by optimizing factors that impact transformation efficiency,and it would ultimately improve research in transgenic B. napus varieties with commercial potential.

Analysis of Correlation between Yield and Quality Traits of Quality Hybrid Rapeseed

[Objective] This study aimed to investigate the correlation between yield and quality traits of rape. [Method] Taking ＂Sanbei 98＂ and ＂Youyan 599＂ as ex- periment materials, correlation between yield and quality traits of Brassica napus L. cultivars was explored by orthogonal rotation method. [Result] The results showed that： 1 In both the two varieties-Sanbei98 and Youyan599, erucic acid content had the largest coefficient of variation, but its average content was lower than 2% in both the two varieties （0.90% in Sanbei98 and 1.24% in Youyan599）, and the palmitic acid content had the smallest coefficient of variation. 2 In terms of the dif- ferences in quality traits at different yield levels, only the mean of eicosenoic acid content revealed significant difference in Sanbei98, and only the mean of seed-pro- tein content revealed significant difference in Youyan599, and there was no signifi- cant difference in any combined quality traits in both the two varieties. 3 The yield was negatively correlated with the erucic acid content or oil content, and posi- tively correlated with the content of seed-protein, linoleic acid, or linolenic acid, and the coefficient of correlation between the yield and either of the contents of glucosi- nolates, oleic acid, palmitic acid, stearic acid, and eicosenoic acid was smaller. ~, when the yield of a variety increased considerably, there was a certain decreasing trend in erucic acid content, oil content, the total amount of erucic chain fatty acids （El ＆ Er）, while there was an increasing trend in seed-protein content, linoleic acid content, linolenic acid content, saturated fatty acids （SFA）, the total amount of fat and protein （P ＆ F）, unsaturation index （IUFA）, unsaturated fatty acids （UFA）, the total amount of 18 carbon fatty acids （18-C FA）, unsaturated fatty acids [UFA/（Ei ＆ Er） ], and the sum of oleic acid and linoleic acid （OI ＆ Li）. 5 When the seed-pro- tein content is increased, the quality of rape oil cake is also improved; when the unsaturated index is increased, the oil stability is decreased. The increase in the total amount of unsaturated fatty acids, oleic acid and linoleic acid helps to increase in the total amount of fatty acids absorbed by human bodies. [Conclusion] This study provides a theoretical foundation for the cultivation of high-yielding and top- quality hybrid rape cultivars.

应用中国和欧洲油菜建立的双二倍体群体对3个重要农艺性状的QTL定位以及与环境的互作分析(英文)

以中国的高油分自交系“高油”和欧洲高含油量品种“Sollux”的F1产生的282个株系组成的双二倍体(DH)群体为材料,在125个SSR标记座位构建的连锁图谱基础上,根据在中国和欧洲四个不同环境下的表型鉴定结果,采用混合线性模型基础上的QTL分析软件,对油菜3个重要农艺性状:株高,开花期和成熟期进行了数量性状基因座位(QTL)的联合定位分析,估测了这些QTL的加性、上位性以及与环境的互作效应。结果表明各性状均受多个加性、加加上位以及与环境互作的QTL控制。株高受多个QTL影响(12个位点具有加性或兼有环境互作效应,5个位点具有互作效应),以加性效应为主,加性效应总和可解释定位群体表型变异的75%左右,并多兼有上位性效应。12个主效QTL中,9个是“高油”等位基因相对“Sollux”有降低株高的作用,大多数加性×环境互作QTL的有效等位基因具有环境选择特异性。7个ae基因座位中,5个“高油”等位基因在杭州种植环境下,除一例外所有在德国环境下的互作基因座中,“Sollux”等位基因起着增加株高的作用,加加上位性主效总和为加性主效总和的三分之一。7个控制花期和8个控制成熟期的主效QTL中,分别有6个和5个是来自“高油”的等位基因相对“Sollux”具有提前开花和成熟的效应,这些QTL的效应总和占到性状表型变异的60%左右。5个位于第2和第12连锁群中的2个大效应QTL可能和已多次报导的VFN1和VFN3基因相近或相同。开花期和成熟期两性状均检测到显著的ae互作效应,双亲等位基因的效应在各环境下呈离散分布。位于14和19连锁群上的两个主效株高QTL同时也是控制开花期和油分含量的基因位点,因而利用这两个位点进行标记辅助筛选时要考虑到对油分含量的影响。控制成熟期的8个主效QTL中有3个同时也是控制开花期的基因座位,证实了开花期和成熟期高度正相关的遗传基础,两个生育性状均表现有较弱的QTL间加加上位互作,但以主效QTL的作用为主。

花分生组织决定基因APETALA1转化油菜

拟南芥的APETALA1(AP1)是花分生组织的决定基因,同时也是萼片和花瓣正常发育的控制因子。本研究构建了含有AP1基因的植物表达载体PCAP,启动子为CaMV35S,通过农杆菌侵染法转化油菜。用PCR方法对转基因植株进行了DNA和RNA水平上的分子检测,证明AP1基因已经整合到转基因植株的基因组中,并且得到了有效的表达。获得的转基因植株也表现出提前开花的特性。试验结果表明,AP1基因在促进成花方面的关键作用不具有种属特异性,利用基因工程可以快速高效地进行油菜早熟性的遗传改良。

早熟油菜成花相关基因LFY的克隆与分析

以甘蓝型油菜晚熟品种RG-8的早熟突变体RG-8M为材料,通过同源克隆法得到1个LEAFY(LFY)同源基因,命名为BnLFY。该基因cDNA全长为1 310bp,包含1个长为1 248bp的开放阅读框,编码415个氨基酸。序列分析表明,推测的氨基酸序列含双子叶植物LFY类蛋白特有的N端脯氨酸富集区、中央酸性区、亮氨酸拉链结构以及富含赖氨酸与精氨酸的碱性区;且与几种十字花科植物LFY类蛋白的氨基酸序列一致性均在84%以上。转录表达分析表明,BnLFY基因在油菜中为组成型表达。

甘蓝型油菜的花期与生育期QTL定位

【目的】对甘蓝型油菜花期和生育期QTL进行定位,为精细定位和克隆早花基因及开展分子标记辅助早熟油菜品种选育提供理论依据。【方法】以极早熟甘蓝型油菜G28、甘蓝型油菜H008及以二者为亲本构建的175个F1DH株系为材料,利用甘蓝型油菜60K SNP芯片分型技术绘制高密度遗传连锁图谱,并采用完备复合区间作图法对2016─2017年度丽江和临沧2个生长环境下甘蓝型油菜的花期(FT)和生育期(MT)田间调查数据进行QTL扫描分析。【结果】F1DH株系花期与生育期具有较明显的超亲现象,表明双亲材料控制花期和生育期的位点不同。F1DH株系在丽江生长环境下花期与生育期相关系数为0.63,在临沧生长环境下二者相关系数为0.79,即花期与生育期呈较高的正相关。利用SNP芯片构建的高密度遗传连锁图谱共包含19条连锁群,7601个SNPs位点,总长3838.2 c M。在丽江和临沧2个生长环境下共检测到6个花期QTL和5个生育期QTL,分布于A02、A07、C02、C03、C06、C07和C09连锁群上,可分别解释2.96%～17.40%和4.98%～11.82%的遗传变异。花期QTL qFTA02-1和qFTC03-2在2生长个环境下均可检测到,加性效应值相反,其中qFTA02-1具有最高的LOD值(20.43)、贡献率(17.40%)和加性效应值(3.27 d),且与生育期QTL qMTA02-1置信区间重叠,是最主要的花期主效QTL;qFTC03-2为次要的花期主效QTL。在qFTA02-1置信区间内发现2个拟南芥花期调控关键基因FLC和FY的油菜同源基因拷贝BnaA02g00370D和BnaA02g01670D。【结论】花期主效QTL qFTA02-1和qFTC03-2可用于分子标记辅助选育早熟油菜品种。BnaA02g00370D和BnaA02g01670D可能为qFTA02-1置信区间内控制甘蓝型油菜花期性状的目标基因。

甘蓝型油菜早熟性状QTL定位及候选基因筛选

目前对于油菜早熟的研究主要围绕开花期性状进行,虽然开花期与生育期呈显著正相关,但却并不完全一致。对于油菜开花后一系列生长发育进程相关性状的遗传研究和QTL定位鲜有报道。本研究以成熟期差异较大的2个油菜品种‘花前早’和‘Global’构建的DH群体为材料,对影响油菜全生育期的各个发育阶段(开花期、花期持续时间、角果期持续时间和全生育期等)进行表型调查和QTL定位分析。共检测到30个早熟相关性状QTL位点,其中开花期、花期持续时间、角果期持续时间和全生育期等分别检测到12、5、4和9个QTL位点,解释了5.8%~22.4%的表型方差。发现4、2和1个全生育期QTL置信区间分别与开花期、花期持续时间、角果期持续时间位点置信区间完全或部分重叠。筛选到29个可能与油菜早熟性状相关的候选基因,它们通过调控花期或籽粒发育等生长发育进程影响油菜早熟。因此,在早熟性状的研究中,可以同时从开花期和籽粒发育过程入手,不但有利于使熟期进一步提前,也可减缓早熟油菜品种过早开花导致的冬前低温寒潮天气的不利影响。

基于ISS-LCG组合特征点的油菜分枝点云配准方法

[目的]针对传统点云配准方法准确率低、速度慢等问题,以油菜Brassica napus L.分枝点云为研究对象,提出基于ISS-LCG组合特征点的配准方法。[方法]以成熟期油菜角果分枝点云为对象,去除背景噪声后,得到清晰完整的油菜分枝点云;然后通过内部形状描述子(Intrinsic shape signature,ISS)提取油菜分枝点云的特征点,再使用线性同余法(Linear congruential generator,LCG)伪随机选取油菜点云的部分点构成关键点,将特征点和关键点进行融合,构成ISS-LCG组合特征点;通过三维形状上下文特征(3D shape context,3DSC)对组合特征点进行特征描述,最后采用RANSAC+ICP两步点云配准法进行点云配准。[结果]基于ISS-LCG组合特征点的点云配准算法以30°为间隔对点云进行两两配准时,配准效果最佳,配准误差约0.066 mm,配准精度比未采用组合特征点的配准方法提升了50%~70%;配准时间均小于48 s,平均配准时间为8.706 s。[结论]该方法在可控环境内可以实现成熟期油菜植株高精度、高效率的自动配准。

油菜开花期QTL定位和候选基因分析

为辅助选育早熟油菜品种、克隆油菜开花期基因及开发花期分子标记,以已测序的油菜品种中双11(Z)和重测序的油菜品系No.73290(N)为亲本构建的含184个单株的BnaZNF2群体为材料,通过分析该群体的基因型数据和F2:3家系连续三年(2010-2012)在武汉的表型数据,对开花期QTL进行检测和整合,定位到分布在11个连锁群上的14个开花期QTL。其中只有5个QTL能在3年中重复检测到,分别是qDtF.A2-1、qDtF.A6-2、qDtF.C2-1、qDtF.C2-2和qDtF.C3-1,贡献率在7.1%~21.1%之间。通过查阅文献和在拟南芥、水稻等作物网站上搜索,搜集到442个与植物开花期有关的基因。基于油菜基因组物理图谱,通过生物信息学分析,在本研究定位的QTL区间上筛选到54个可能的候选基因,可以用于开花期基因的克隆。在5个主要QTL区间内分别定位到8、5、4、2和4个候选基因,其中有15个在双亲中存在序列差异,可以开发开花期的功能标记用于分子标记辅助选择育种。

特早熟甘蓝型双低油菜杂交种青杂3号的选育

青杂3号(原代号为E144)是青海省春油菜研究开发中心培育的甘蓝型双低油菜波里马细胞质雄性不育三系杂交种。在国家春油菜区域试验早熟组中平均产量为2340.1kg/hm2,比对照白菜型油菜品种青油241增产39.3%;在国家春油菜生产试验中平均产量为2407.5kg/hm2,比对照青油241增产45.1%。在青海省区域试验中平均产量为2790.2kg/hm2,比对照青油241增产47.6%;在青海省生产试验中平均产量为2989.1kg/hm2,比对照青油241增产50.2%。青杂3号种子含油量44.27%,芥酸含量0.50%,硫甙含量29.40μmol/g。全生育期110d左右。

不同甘蓝型油菜品种磷营养效率的差异研究

采用两步筛选法 (即苗期干物质筛选和全生育期产量筛选 )在酸性黄棕壤上对 194个甘蓝型油菜品种进行了磷效率的筛选。本研究以磷效率系数来反映品种间的差异 ,将其定义为缺磷和加磷条件下的干物质量及产量等指标的比值 (-P/ +P) ,在苗期筛选时 ,设置两个处理 (-P :0 .0 10g/kg ,+P :0 .10 0g/kg ,以纯养分计 ,下同 ) ,32d后收获 ,根据干物质量得到苗期磷效率系数 ,其变幅在 0 .0 5 0～ 0 .6 15之间 ,呈正态分布。根据苗期长势长相从其中选出 12个具有代表性的品种进入全生育期筛选 ,设置两个处理 (-P :0 .0 2 0g/kg ,+P :0 .10 0g/kg) ,收获得到菜籽产量 ,以产量效率系数 (变幅在 0 .134～ 0 .30 5之间 )为基准 ,结合各品种在蕾期 ,花期 ,角果期 ,成熟期对磷营养的不同反应 ,最终确定甘蓝型油菜磷高效品种 970 81和磷低效品种 970 2 9。

SRAP和SSR标记构建的甘蓝型油菜品种指纹图谱比较

利用SRAP(sequence-related amp lified polymorph ism)和SSR标记构建了甘蓝型油菜品种指纹图谱,并对两种标记方法进行了比较。结果表明:(1)每对SRAP引物扩增出20.36个条带,其中4.44个是清晰、易于辩认的多态性带;每对SSR引物扩增出3.88个条带,均为多态性条带。(2)采用25对SRAP和SSR引物分别构建40个和75个品种的特异指纹图谱,SRAP指纹中具有特异图谱的比例(82.5%和50.7%)高于SSR指纹图谱的结果(60.0%和44.4%)。品种数越多具有特异指纹的品种越少。(3)运用引物组合法构建品种指纹图谱,大大地提高了指纹图谱的特异性。25对SSR引物组合扩增97个多态性谱带,两个不同的品种具有相同谱带的概率只有6.3108×10-30。组合指纹图谱比组合数码图谱更直观。与SRAP标记相比,SSR标记以其扩增谱带少、易于识别和统计而更适合用于引物组合法构建品种指纹图谱。

氮磷钾肥施用对油菜产量及养分吸收利用的影响

为油菜科学施肥提供依据，利用当前推广的6个油菜品种秦优11号（QY11）、中农油2008（ZNY2008）、中油杂11号（ZYZ11）、湘油17（XY17）、浙油601（ZY601）和沪油杂1号（HYZ1），在大田试验条件下研究了氮、磷、钾肥施用对油菜产量及氮、磷、钾素吸收利用的影响，并比较了不同品种对施肥响应的差异。结果显示，相同施肥处理下不同品种籽粒产量差异显著，不施N（PKB）、不施P（NKB）、不施K（NPB）及NPK全施（NPKB）处理下品种间最大差异分别为385、244、759和720kg/hm2，变异系数分别为18．1％、25．5％、16．4％和11．0％。氮、磷、钾施用可显著提高各品种产量和相应养分积累量，NPKB处理相比PKB、NKB及NPB处理分别增产1101～2012、1681～2459和293～1567kg/hm2，N、P、K积累量分别增加63．0～113．2、17．2～23．8和94．1～166．3kg/hm2。不同品种氮、磷、钾肥利用率也存在显著差异。同一品种对氮、磷、钾的响应一致，其中秦优11号对氮、磷、钾肥施用的敏感程度均大于其它品种，湘油17耐低氮、低磷和低钾的能力均高于其它品种。

密植油菜苗期和成熟期性状与产量的相关性

对油菜幼苗期和成熟期各性状进行分析,探讨在高密度下油菜苗期冠层特性和成熟期农艺性状与产量的相关性,为选育适合高密度栽培的油菜品种提供理论依据。通过相关性和主成分分析,结果表明,在油菜幼苗期不同叶型品种(系)的冠层覆盖面积和叶片重合面积不同,有显著性差异,其冠层覆盖面积越大,叶片重合面积越大;其中以叶片重合面积、分枝部位和分枝数的变异系数最大,说明在株型方面有较大的改良空间;在相关性分析中,株高、主花序长、主花序角果数、单株有效角果数、每角粒数、冠层覆盖面积与单株产量呈显著正相关,叶片重合面积与单株产量呈显著负相关。利用主成分分析,可将相关农艺性状分为"产量贡献因子"、"密植株型因子"、"丰产遗传因子"、"密植苗形因子"4大类,在主成分综合评价中以ZX5的得分最高,ZX1得分最低。合理的性状特征是密植高产的基础。

油菜早熟突变体成花过程中叶片多胺代谢研究

以甘蓝型油菜品种‘福油-4’、RG-8晚熟及其早熟突变体(RG-8M)为材料,研究成花过程中叶片多胺代谢的变化规律,结果表明:较低含量的多胺(主要是腐胺和亚精胺)有利于油菜花芽分化的起始,含量的增加有利于花芽的发育,抽薹越早的品种其体内多胺含量越早到达较高水平。多胺氧化酶(PAO)活性的变化趋势与多胺总量的变化较一致,它们之间呈极显著正相关,说明高活性的PAO也是有利于成花的。

硼对甘蓝型油菜不同品种花期生理特性的影响

土培条件下研究硼对甘蓝型油菜缺硼敏感与不敏感品种花期某些生理特性的影响。结果表明：缺硼使敏感品种花期下部叶片中蛋白酶、肽酶、酸性磷酸酯酶活性降低，而不敏感品种有升高趋势。缺硼后敏感品种下部叶片中Ｎ、Ｐ、Ｋ养分的再利用能力降低，而不敏感品种仍有一定数量的养分可以再利用。缺硼还使油菜花药和雌蕊中淀粉、可溶性糖、游离脯氨酸、可溶性蛋白质含量及花粉活力降低，敏感品种降低幅度明显大于不敏感品种。