Fast tracking alien gene discovery by molecular markers in a late flowering Chinese cabbage-cabbage translocation line‘AT7–4'

Flowering time is an important agronomic trait of Chinese cabbage with late flowering being a primary breeding objective.In our previous work,we obtained Chinese cabbage-cabbage translocation lines that contained several beneficial cabbage genes.Cabbage-specific molecular markers show that these genes were coming from chromosome C01 of cabbage.In this study,we investigated the inheritance of flowering time in a couple of translocation lines and analyzed the transmission rate of molecular markers in the offspring.Consequently,we obtained the late flowering Chinese cabbage-cabbage translocation line‘AT7–4’in which the flowering time was later than that of‘85–1’by about 7 days under 4-week vernalization.Based on previous studies of the genomes of Chinese cabbage and cabbage,we located the cabbage-specific molecular markers that were closely linked at the top of the chromosome A01 in the F2mapping population generated by self-crossing F1s derived from a cross between the translocation line‘AT7–4’and Chinese cabbage‘14–36’.Five flowering-related genes in the alien fragment were found by functional annotation and their molecular markers were developed.This study lays the foundation for the future improvement of Chinese cabbage varieties using A-C translocation lines.

Effect of Foliar Application of Amino Acid on the Quality and Enzyme Activity of Flowering Chinese Cabbage(Brassica parachinensis Bailey)

A pot experiment was conducted to study the influences of foliar application of glycine,alanine,lysine,and glutamic acid in 200 mg/kg or 500 mg/kg upon the quality and enzyme activity of flowering Chinese cabbage（Brassica parachinensis Bailey）.The results showed that all the application of these four amino acids could increase the yield of flowering Chinese cabbage,significantly raise the content of soluble sugar,and reduce the accumulation of nitrate.The applications of three other amino acids except alanine can increase the content of soluble proteins and decrease the accumulation of oxalic acid.However,the application of amino acid has insignificant influences on the SPAD number of chlorophyll,and causes the decrease of Vitamin C content.Meanwhile,the application of amino acid can improve the activity of nitrate reductase（NR） and glutamate dehydrogenase（GDH） as well.It shows that the application of amino acid is beneficial to improve ammonia metabolism,reduce the accumulation of nitrate and oxalic acid,increase the content of soluble sugar and soluble proteins,and improve the quality of flowering Chinese cabbage.

Experimental Study on No-tillage Cultivation of Flowering Chinese Cabbage in Rice Winter Fallow Fields

The research made comparisons on no-tillage cultivation and ploughing cultivations of Flowering Chinese cabbage on one-season paddy fields and explored the effects of no-tillage cultivation of Flowering Chinese cabbage on survival rate, insect damages, production cost, yield and benefits of plants. The results indicated that no-tillage cultivation reduced the injured rate of Flowering Chinese cabbage by cutworms, and production cost, but crop yield and output value declined as well. Specifically, yield in the treatment as per no-tillage cultivation lowered by 10.3% and 11.9% compared with the treatments by machine-based ploughing and manual ploughing, and the production interests declined by 11.9% and 11.1%, accordingly.

Effects of SPNE on Yield and Biochemical Quality of Hybrid Flowering Chinese Cabbage

Objective] The effects of SPNE on the yield and biochemical quality of flowering Chinese cabbage were investigated in this study. [Method] The special plant nutritional element （SPNE） was sprayed on the flowering Chinese cabbage plants after the beginning of harvesting. The effects of SPNE on the yield traits and biochemical quality traits of flowering Chinese cabbage were investigated in the un-conventional using period. [Results] The results showed the flowering stalk of flow-ering Chinese cabbage developed earlier and grew fasterly for the SPNE treatment;the diameter, length and weight of flowering stalk of SPNE-treated flowering Chi-nese cabbage were al higher than that of control. The SPNE treatment could not only increase yield, but also bring better biochemical quality. The protein, vitamin C and calcium contents, especial y the chlorophyl and sugar contents in the SPNE-treated flowering Chinese cabbage were al higher than that of control, making the SPNE-treated flowering Chinese cabbage taste better. [Conclusion] lt was indicated although sprayed after the beginning of harvesting, the SPNE had a certain effect on the flowering Chinese cabbage.

Monosomic Addition Lines of Flowering Chinese Cabbage(B.campestris L.ssp.chinensis var.parachinensis L.H.Bailey)-Chinese Kale(B.oleracea L.var.alboglabra L.H.Bailey)

Interspecific alien addition lines have played significant roles in gene mapping, intergenomic gene transfer and chromosomal homoeological identification between closely related species. Selection of alien addition lines was conducted by karyotype analysis and morphological observation with the reference of parents. Triploid interspecies hybrid （AAC, 2n = 3x = 29） was obtained from Brassica campestris ssp. chinensis var. parachinensis Qinglu 9601 （tetraploid, AAAA, 2n = 4x = 40） x B. oleracea var. alboglabra Baihua 9705 （diploid, CC, 2n = 2x = 18） by immature hybrid embryo culture in vitro. Five different alien monosomic addition lines （AA ＋ C2, AA ＋ C3, AA ＋ C4, AA ＋ C6, AA ＋ C7） were obtained from the backcross progenies of AAC x AA. Each alien monosomic addition line has some specific morphological characters. It is feasible to obtain alien addition lines from the progenies of AAC × AA by karyotype analysis and morphological observation based on the reference of parents

Design and experiment of the pneumatic double disc precision seed metering device for Chinese flowering cabbage

Single seed metering devices for Chinese flowering cabbage planting machines have suffered such deficiencies as low efficiency,poor accuracy,and instability.To overcome these limitations,a pneumatic double disc precision seed metering device was designed.This innovative device can simultaneously plant four rows,considering the specific agricultural requirements and the geometric characteristics for Chinese flowering cabbage seeds.The precise parameters of the key component seed disc were derived through theoretical calculation.In addition,a detailed account was given for the working principle and workflow of the seed metering device.The discrete element method and EDEM software were employed to optimize the seed disc by exploring the effects of seed disc rotational speed and interleaving seed slots on seed viability.Orthogonal rotation experiments were conducted to evaluate the impact of seed disc rotational speed and negative pressure.While rates of qualified seeding,double seeding and missing seeding were adopted as test indicators.Testing results show that,at a seed disc rotational speed of 41.5 r/min and a negative pressure of 3.80 kPa,the average qualified seeding rate is 90.13%,the average missing seeding rate is 3.30%,and the average double seeding rate is 6.02%.These values satisfy the agricultural requirements for planting Chinese flowering cabbage.The findings can also provide valuable insights for the structural optimization and design of precision seed metering devices for Chinese flowering cabbage.

Molecular Characterization of a Leaf Senescence-Related Transcription Factor BrWRKY75 of Chinese Flowering Cabbage

WRKY is a plant-specific transcription factor(TF) involved in the regulation of many biological processes; however, its role in leaf senescence of leafy vegetables remains unknown. In the present work, a WRKY TF, termed Br WRKY75 was isolated from Chinese flowering cabbage [Brassica rapa L. ssp. chinensis(L.) Mokino var. utilis Tsen et Lee]. Analysis of deduced amino acid sequence and the phylogenetic tree showed that Br WRKY75 has high homology with WRKY75 from Brassica oleracea and Arabidopsis thaliana, and belongs to the II c sub-group. Sub-cellular localization and transcriptional activity analysis revealed that Br WRKY75 is a nuclear protein with transcriptional repression activity, and was up-regulated during leaf senescence. Electrophoretic mobility shift assay confirmed that Br WRKY75 directly bound to the W-box(TTGAC) cis-element. Collectively,these results provide a basis for further investigation of the transcriptional regulation of Chinese flowering cabbage leaf senescence.

不同菜心品种对软腐病的抗性鉴定

【目的】近年来,随着菜心栽培面积扩大和重茬现象的出现,菜心病害逐年加重,其中软腐病是危害菜心的主要病害之一,严重影响其产量和品质。通过接种软腐病病菌对菜心品种进行抗病性评价,以期筛选出抗病品种。【方法】采集具有典型软腐症状的菜心病样,通过组织分离、形态学和分子生物学方法进行鉴定,获得软腐病病菌。以52份不同菜心品种为试验材料,采用苗期喷雾接种法进行接种:用刀片在菜心茎部轻划2个约5mm刀口,使用小型手持喷雾器将1×108CFU/mL菌液喷到伤口表面,接种完成后3 d,测定病情指数和软腐病分级,评价52份菜心品种的软腐病抗性水平。【结果】经组织分离得到分离物,经柯赫氏法则验证菌落形态特征、16S rDNA序列分析表明,菌株为菜心软腐病致病菌,在NA培养基上形成的菌落呈圆形、半透明、乳白色、中心突起、边缘平滑,能使菜心的组织腐烂,接种于菜心苗后叶片呈湿腐萎蔫症状。52份材料中,大多数菜心品种对软腐病的抗性存在显著差异,其中,高感材料35份、感病材料16份,整体而言,高感或感病材料占98.1%;中抗材料1份(丰裕4号菜心);无高抗或免疫品种。上述结果表明,52份菜心品种中抗软腐病的材料较少,这可能是广东省菜心软腐病发病较严重的原因之一。【结论】52份菜心品种中,软腐病高感或感病材料占98.1%;中抗材料1份;无高抗或免疫品种,可为选育和推广抗软腐病的菜心品种提供科学依据。

不同浓度硒肥对菜心生长及品质的影响

【目的】探明不同浓度硒肥对菜心生长和营养品质的影响,筛选外源硒肥喷施菜心的最佳条件,为富硒菜心生产提供理论依据。【方法】以油青尖叶甜菜心为研究对象,采用温室大棚盆栽试验,设置5个硒肥浓度水平(单次施肥量):CK(0μg/盆)、T1(3.375μg/盆)、T2(6.75μg/盆)、T3(10.125μg/盆)、T4(13.5μg/盆),研究菜心不同生长时期土壤根施(追施硒肥时间为每次取样后第3天下午进行,共追施3次)硒肥对菜心生长及品质的影响。【结果】与CK相比,不同浓度硒肥处理可促进菜心生长,菜心增粗增高,叶面积和地上部鲜重随硒肥浓度增加总体呈增加趋势,硒肥浓度为10.125μg/盆时播后43 d菜心的茎粗、株高、叶面积和地上部鲜重均达最大。适宜浓度硒肥能提升菜心品质,硒肥浓度在13.5μg/盆时菜心叶片的叶绿素和维生素C含量最高,硒肥浓度在6.75μg/盆时菜心叶片的可溶性蛋白质含量最高。随硒肥浓度增加菜心叶片的硝酸盐含量逐渐下降。【结论】增施硒肥对菜心生长发育有一定促进作用,硒肥浓度在6.75~10.125μg/盆时,能有效促进菜心的生长发育,提高菜心的产量和品质。

基于游离小孢子培养的菜心DH系评价

为筛选优良菜心DH系,采用田间试验方法,对游离小孢子培养获得的再生植株(DH系)的园艺学性状进行观察和鉴定。结果表明,获得了41份菜心DH系,经综合评价筛选出12个综合性状表现较好的DH系。这些材料的获得有助于丰富菜心种质资源,可为杂交亲本的选择和配组提供参考。

电生理快速定量菜心杂种优势

本研究以温室培养的14个品种的菜心为材料,测定了饱水与不饱水状态下菜心的基本电生理参数,并基于能斯特(Nernst)方程计算得到叶片相对持水量(LIWHC)、叶片胞内水分转移速率(LIWTR)、叶片胞内持水时间(LIWHT)、叶片营养主动传输能力(NAT)、叶片营养被动传输能力(NPT)、耐低营养能力(RLN)、营养利用效率(NUE)和植物相对代谢活力(MA)等电生理指标,探究其与杂种优势的关系。结果表明,杂交50的胞内水分传输效率均显著低于其他品种的菜心,其RLN和NUE值则显著高于其他品种,但MA则显著高于其他品种。采用隶属函数法对供试品种水分及养分代谢进行综合评价,结果表明,参试的4个品种中,菜心杂交50的综合评价优于其他3个品种。因此,可以通过测定植物的电生理信息来计算水分、养分代谢状况以及植物的相对代谢活力等来鉴定植物的杂种优势。

基于模糊控制的设施菜心生产环境管控模型及系统

【目的】为实现设施菜心生产环境的实时监控和精准调控,设计一种基于模糊控制的设施菜心生产环境管控模型及系统。【方法】采用物联网设备实时监测菜心各生长阶段(种子发芽期、叶片生长期、菜薹形成期)的环境因子(空气温度、土壤温度、土壤湿度和土壤电导率),将参数的监测值与适宜范围进行对比,获得各环境因子的偏差及变化率。管控模型利用模糊推理与定性分析结合的方法优化环境因子控制量,确定环境调控设备的调控决策,达到对环境因子的精准调控。【结果】管理模式对比试验表明:在菜心3个生长阶段,管控系统模式的平均调控实时性指标分别为0.10、0.17和0.18,平均准确性指标分别为0.78、0.68和0.74;人工管理模式的平均调控实时性指标分别为0.37、0.41和0.43,平均准确性指标分别为0.31、0.34和0.30。管控系统的平均实时性和准确性与人工管理模式相比分别有62.50%和1.34倍的提升。【结论】管控系统模式实现了菜心生产环境信息的实时获取与精准调控,能帮助用户更好地进行设施菜心的生产管理。

微生物菌剂对菜心种子萌发及幼苗生长的影响

为探究微生物菌剂对菜心种子萌发及幼苗生长的影响,用10种微生物菌剂分别对菜心种子和菜心幼苗进行处理,研究了不同微生物菌剂对菜心种子发芽指数、幼苗生物量、壮苗指数、根系构型和光合色素含量的影响。结果表明,添加外源稀释400倍的微生物菌剂后,菜心种子发芽指数、幼苗壮苗指数、根系长度、根系表面积、根系体积和叶绿素(a+b)含量均得到不同程度提高。其中种子发芽指数以内生普里斯特氏菌(T1)处理较高,较清水(CK1)处理高出40.7%;幼苗壮苗指数和根系长度以耐盐芽孢杆菌(T4)处理较高,分别较营养液(CK2)处理高出50.0%和87.7%;根系表面积、根系体积、根系平均直径和叶绿素(a+b)含量以T1处理较高,分别较营养液(CK2)处理高出154.4%、89.7%、13.5%和19.3%,差异显著。隶属函数结果表明,稀释400倍的内生普里斯特氏菌(Priestia endophytica)处理对菜心促生作用最好。

4种功能性肥料对菜心生长和品质的影响

为筛选出适宜菜心栽培的功能性肥料,本研究探讨PSO_(4)菌株发酵液(PSO_(4))、玉米提取液(CE)、水解羽毛粉(HFP)、肌醇粉(IN)4种不同成分的功能性肥料对菜心生长及品质的影响。结果表明,适宜的4种功能性肥料对菜心均有显著增产作用,增产幅度为IN>HFP>PSO_(4)>CE。HFP和IN促进菜心根系横向生长,PSO_(4)促进菜心根系纵向生长,同时显著提升可溶性固溶物、可溶性糖及维生素C含量,从而提高菜心品质。在菜心栽培中,PSO_(4)和CE的最适宜浓度为300倍稀释浓度,HFP最适宜浓度为0.05%,IN最适宜浓度为0.1%。研究结果可为4种功能性肥料在菜心生产和品质栽培中的应用提供一定的理论依据。

同源四倍体菜薹新材料的创制与品质分析

[目的]本文旨在创制优质的菜薹四倍体新材料。[方法]用2 g·L^(-1)秋水仙素溶液点滴二倍体菜薹LCX019幼苗的子叶生长点,通过形态学、解剖学、细胞学与流式细胞仪的方式筛选鉴定出同源四倍体植株,并对二、四倍体植株的农艺性状以及品质特性进行分析比较。[结果]形态学与解剖学结果显示,同源四倍体菜薹在株型、叶片、花、种荚、菜薹等方面表现出“巨大性”的特点;气孔孔径变大,气孔密度下降;花粉粒体积相比二倍体增大,形状呈橄榄球形或不规则形状。细胞学结果显示,四倍体菜薹根尖染色体数目为二倍体的2倍;流式细胞仪的分析结果表明,四倍体的DNA荧光强度约为二倍体的2倍。四倍体菜薹的可溶性糖、有机酸及纤维素含量显著增加76.17%、13.71%和80.34%,叶绿素含量、硝态氮含量显著下降25.01%、45.10%,可溶性蛋白含量无显著变化。通过分析二、四倍体的光响应曲线与光合特性,发现四倍体菜薹LCX019对弱光的利用能力强于二倍体植株。[结论]获得了具有优良品质的菜薹同源四倍体新材料,为菜薹育种提供新的种质资源。

基于转录组测序的菜心茎尖组织开花相关基因差异表达分析

【目的】基于转录组测序数据分析鉴定调控菜心抽薹开花相关的候选基因及信号通路,为今后阐明菜心抽薹开花调控分子机制及选育不同熟性菜心品种提供理论参考。【方法】对四九-19号(早熟型)和80天油绿(晚熟型)菜心的七叶期和现蕾期茎尖组织进行转录组测序,比较不同熟性菜心品种间及不同生长时期间的差异表达基因(DEGs),并对其进行GO功能注释及KEGG信号通路富集分析,结合FLOR-ID和UniProt数据库筛选出不同熟性菜心参与调控抽薹开花时间的候选基因及信号通路,通过实时荧光定量PCR验证转录组数据的可靠性。【结果】菜心茎尖组织转录组测序数据为81.93 Gb,经质控过滤后得到536679570条Clean reads,GC含量为47.24%~47.63%,Q20为97.11%~98.00%,Q30为91.97%~94.11%,平均87.98%的Clean reads比对上参考基因组。四九-19号菜心的七叶期和现蕾期间有1965个DEGs,80天油绿菜心的七叶期和现蕾期有6007个DEGs。GO功能注释结果显示,涉及分子功能的DEGs最多,主要注释为蛋白质二聚化活性、血红素结合和四吡咯结合等;其次是生物学过程,主要注释为小分子代谢过程、脂质代谢过程和离子运输等过程;细胞成分类别中,DEGs主要注释为核糖体、细胞器部分、染色体、核小体、蛋白质-DNA复合物和DNA包装复合体。KEGG信号通路富集结果显示,四九-19号菜心七叶期和现蕾期间的DEGs显著(Padj<0.05,下同)富集在光合生物中的碳固定及角质、木栓质和蜡生物合成等通路;80天油绿菜心七叶期和现蕾期间的DEGs显著富集在苯丙素生物合成、DNA复制和植物激素信号转导等通路。四九-19号和80天油绿菜心品种间有750个DEGs,其中16个为开花相关基因,涉及光周期途径、自主途径、赤霉素途径、春化途径、温度途径和年龄途径等,部分开花基因在2个菜心品种中表达量存在明显差异。实时荧光定量PCR检测结果与转录组测序结果相关性较强。【结论】菜心抽薹开花过程受到光周期途径、自主途径和赤霉素途径等关键途径调控,同时受到春化途径、温度途径和年龄途径的影响。虽然2个不同熟性菜心品种开花调控所涉及的途径基本相同,但开花调控途径中的基因响应不一致,导致二者开花时间存在差异。

优质同源四倍体菜心新材料的创制及特性分析

为获得优质的菜心同源四倍体新材料,本研究采用0.2%(W/V)的秋水仙素溶液点滴二倍体菜心LCX017幼苗子叶生长点,通过形态学、解剖学、细胞学以及流式细胞仪等方式鉴定到诱导成功的同源四倍体植株,并对二、四倍体的农艺性状、营养品质、光合特性等方面进行分析比较。结果表明,形态学与农艺性状方面,四倍体植株在叶片、花器官、种荚等方面表现出“巨大性”,叶宽、叶厚增大,菜薹直径变粗,重量增大;解剖学方面,四倍体叶片气孔相对二倍体更大,气孔密度降低;花粉粒相比二倍体变大且呈现棒状或橄榄状;细胞学方面,四倍体植株的根尖染色体数目是二倍体的2倍;流式细胞仪鉴定结果显示,四倍体的DNA荧光强度是二倍体的2倍;营养品质方面,相较于二倍体,四倍体植株中可溶性糖、纤维素、有机酸以及叶绿素含量显著上升,硝态氮含量下降22.92%,可溶性蛋白含量无显著变化;此外,结合光响应曲线分析发现,四倍体在强光和弱光条件下的适应能力均强于二倍体。综上,本研究成功诱导出了优质的同源四倍体菜心新材料,丰富了不结球白菜的种质资源。

基于RAD-seq的菜心InDel标记开发及应用

【目的】开发多态性丰富的的InDel分子标记,为菜心育种提供研究基础。【方法】以Chiifu-401-42的基因组序列为模板,利用4份菜心材料的RAD-seq重测序数据,在全基因组范围内鉴定InDel位点。利用生物信息学方法筛选4份菜心材料间具有潜在多态性的InDel位点,挑选分布于10条染色体的80个InDel位点设计引物,对55份菜心种质材料进行遗传多样评价。【结果】通过与参考基因组序列比对,在4份菜心材料的重测序数据中共鉴定出84510个InDel位点,其中插入/缺失长度大于5 bp的3609个InDel位点在4份菜心材料间具有潜在多态性。挑选80个InDel位点进行PCR扩增验证,58个(72.5%)在4份测序样品中具有多态性,在55份菜心种质材料中检测到133个等位位点,多态性信息含量(PIC)为0.263~0.618,平均值为0.443。基于InDel标记的检测结果可知,55份菜心种质的遗传相似系数在0.366~0.756,平均值为0.570;在遗传相似系数为0.564时55份菜心种质被分为4个类群,但各类群间的耐热性没有明显差异。【结论】本研究开发的InDel标记具有良好的多态性,能有效地揭示不同菜心种质材料间的遗传距离,可为菜心遗传种质分析、新品种选育等方面提供可利用的标记信息。

不同施钾处理对甘蓝型油菜菜薹产量和品质的影响

为了探究不同施钾技术对甘蓝型油菜菜薹产量和品质的影响,笔者通过对高钾含量品种(玉油7号)、较高钾含量品种(中双8号)和低钾含量品种(保油10号)进行不同施钾处理,摘取菜薹进行产量和品质指标测定。结果表明,不同施钾处理能提高菜薹产量,玉油7号产量有所增加,但其产量远低于其他2个油菜品种,中双8号在T3处理下菜薹产量最高(20.66 kg·小区^(-1)),保油10号在T8处理下菜薹产量最高(23.30 kg·小区^(-1));中双8号在T1处理下菜薹可溶性糖和可溶性蛋白质含量最高,T3处理下钾含量最高,T4处理下游离氨基酸含量最高,而保油10号在T2处理下综合营养品质最高。高钾含量油菜品种玉油7号不适合作为摘薹品种,中双8号提高施钾量有利于油菜菜薹产量和品质的提高,保油10号在抽薹期追施钾肥有利于菜薹产量的增加,一定范围内提高施钾量也有利于其营养品质的提高。

化肥减量处理下蚯蚓-牛粪协同作用对菜薹生长及土壤中重金属锌、砷和铬含量的影响

为了探究化肥减量施用处理下协同施用蚯蚓-牛粪对菜薹生长及土壤重金属含量的影响,以菜薹和种植土壤为研究对象,采用盆栽试验方法,设置常规施肥(CK)、化肥减量30%+蚯蚓(CE)、腐熟牛粪+蚯蚓(FE)、化肥减量30%+腐熟牛粪(CFC)及化肥减量30%+腐熟牛粪+蚯蚓(CFE)共5个组别进行试验。结果表明,与CK相比,CFE处理显著提高了菜薹的生长性状指标(P<0.05),包括株高、茎粗、总根系长度、根系总表面积、根系总体积和平均单根直径等。同时,蚯蚓的引入优化了土壤结构,增加了土壤养分含量,与CK及CFC处理相比,CFE处理的土壤pH值显著降低(P<0.05);与CK相比,CFE处理的电导率(EC)、土壤有机质(SOM)含量、全氮(TN)含量、速效氮(AN)含量显著升高(P<0.05)。此外,与CK相比,CFE处理显著降低了土壤中的砷、铬含量(P<0.05),显著增加了锌含量(P<0.05)。关于土壤理化性状对菜薹生长影响的研究发现,全氮含量、速效氮含量和速效磷含量是能共同影响菜薹株高、茎粗的土壤理化性状,而电导率、土壤有机质含量则会显著影响菜薹总根系长度和根系活力。综上,化肥减量30%+腐熟牛粪+蚯蚓联合处理在促进菜薹生长发育、优化土壤理化性状及降低土壤重金属污染方面具有潜在应用价值。