Effect of Combined Use of Boron and Manganese Fertilizers on the Nutritional Quality and Physiological Indices of Brassica campestris L.ssp.chinensis L.var.utilis

[Objective] The purpose of this study is to determine the effects of com-bined use of boron and manganese fertilizers on the nutritional quality and physio-logical indices of Brassica campestris. [Method] In the nutrient solutions for growing B. campestris by hydroponics, boric acid and manganese sulfate were added at 0.5, 2.5, and 7.5 mg/L respectively. Another treatment without boron and manganese was prepared as the control. Quality and physiological indices of B. campestris in the 10 treatments were measured. [Result] Boron and manganese shared obvious in-teraction in improving the quality and physiological indices of B. campestris. To cul-tivate B. campestris with high quality and strong resistance, the optimum concentra-tions of boron and manganese in the nutrient solution should be 2.5 mg/L boric acid and 2.5-7.5 mg/L manganese sulfate. [Conclusion] The findings wil provide refer-ence for studying effects of trace elements on nutrient composition of vegetables.

Effect of Nitrogen and Sulfur Supply on Glucosinolates in Brassica campestris ssp.chinensis

Glucosinolates （GSs） are a group of plant secondary metabolites containing abundant nitrogen （N） and sulfur （S） mainly in Brassica and have the beneficial effects on human health including anti-carcinogenic, cholesterol-reducing and other pharmacological effects. The objective of this study was to investigate the effect of different concentrations of N （5, 10, and 20 mmol L-a, denoted by N5, N10 and N20） and S （0,5, 1, and 2 mmol L^-1, denoted by S0.5, S1 and S2） on the yield and GSs in pakchoi （Brassica campestris L. ssp. chinensis var. communis） in hydroponics. Results showed that N10 and N20 significantly enhanced the yield compared with N5, however, N20 had a negative effect relative to N10. Only with N10 and N20 low S supply （S0.5） reduced the yield. The concentrations of aliphatic GSs, aromatic GS and total GSs were enhanced by N5 and indolyl GSs were enhanced by N20. S2 enhanced the concentration of individual GS and total GSs. The concentrations of indolyl GSs were maximized in N20S2 treatment, whereas the highest concentrations of aliphatic GSs, aromatic GS and total GSs were found in N5S2 treatment. Effects of N and S on aliphatic GSs were higher than on indolyl GSs. The results suggest that the accumulation of aliphatic GSs and aromatic GS could be enhanced by low N and high S and restricted by high N while that of indolyl GSs could be enhanced by high N and high S.

Effect of the Antisense BcMF12 Driven by the BcA9 Promoter on Gene Silencing in Brassica campestris L.ssp.chinensis

The study analyzed the silencing of BcMF12 gene regulated by BcA9 promoter in the transgenic pakchoi and confirmed the effect of antisense BcMF12 gene on the pollen development. A conserved BcMF12 gene fragment was amplified from the cDNA of flower buds in pakchoi （Brassica campestris L. ssp. chinensis, syn. B. rapa L. ssp. chinensis） and was fused to the anther specific BcA9 promoter. The plant antisense expression vector was constructed and then introduced into pakchoi via Agrobacterium-mediated transformation. The transgenic plants were screened by antibiotics and molecular analysis. PCR and Southern blot revealed that the antisense BcMF12-GUS fusion gene regulated by BcA9 promoter was integrated into transgenic plants. Northern blot suggested that the expression of BcMF12 gene was down-regulated significantly. The pollen germination rate of transgenic plants with antisense BcMF12 gene decreased as compared with that of the control plants. The expression of the gene BcMF12 related to the pollen development was inhibited by the antisense BcMF12 driven by BcA9 promoter, which consequently affected the pollen development in pakchoi.

Effects of Different Cadmium Levels on Active Oxygen Metabolism and H_2O_2-Scavenging System in Brassica campestris L.ssp.chinensis

The effects of different Cd (Cadmium) levels on generation of active oxygen speceies(AOS) and H2O2-scavenging system in the leaves of Brassica campestris L. ssp. chinensiswere studied. The results showed that generation rate, and H2O2 content were enhancedand malondialdehyde (MDA) content increased with the increase of Cd concentrations inthe growth medium. The activities of ascorbate peroxidase (APX), dehydroascorbatereductase (DR) and glutathione reductase (GR) were promoted by the addition of Cd.Exposed to Cd also increased the contents of ascorbate (AsA) and glutathione (GSH) in theleaves.

不结球白菜(Brassi cacampestris ssp.chinensis Makino)种质资源SRAP遗传分化分析

利用SRAP分子标记分析了国内外64份不结球白菜种质资源的DNA遗传多样性和遗传分化。21对引物组合共检测出215个位点,其中112个为多态性位点,多态性比率达52.09%,平均每对引物组合产生10.24个位点和5.33个多态性位点。不结球白菜各类型中普通白菜的Nei’s基因多样性指数(0.1410)和遗传丰富度[(190)88.37%]最高;各生态区域中江淮流域不结球白菜的Nei’s基因多样性指数(0.1451)和遗传丰富度[(185)86.05%]最高;国内的Nei’s基因多样性指数(0.1293)和遗传丰富度[(188)87.44%]分别高于国外。遗传变异估算表明,不结球白菜遗传分化系数58.22%,大部分变异存在于种群间;基因流为0.4031,说明群体间基因流动较少,遗传分化程度较高。以遗传相似系数0.872为截值,可把不结球球白菜分为Ⅵ个类群。

Research Progress of Heat-tolerance of Brassica campestris ssp. Chinensis

Brassica campestris ssp. chinensis, also known as non-heading Chinese cabbage, is an important vegetable widely distributed in southern China. High temperature is the most common adversity factor in vegetable production, because Brassica campestris ssp. chinensis is a thermophilic vegetable, which can＇t well grow at high temperature. In summer and autumn, high temperature stress would prevent Brassica campestris ssp. chinensis from growing and result in poor quality of its seedlings, seriously influencing yield and quality of the vegetable in later period. In this paper, present situation and latest advances in heat resistance research of Brassica campestris ssp. chinensis in recent years were reviewed at home and abroad. The research tendency in Bassica campestris ssp. chinensis was also described, providing reference for breeding of heat-resistant Brassica campestris ssp. chinensis.

Genetic Inheritance and Molecular Marker of Clubroot Resistance Genes in Brassica campestris ssp. chinensis

Objective] This study was conducted to investigate the genetic inheritance of clubroot resistance in Chinese non-heading cabbage （Brassica campestris ssp. chinensis）. [Method] The clubroot resistance gene was introduced from a Brassica campestris ssp. pekinensis cultivar to non-heading Chinese cabbage, and the inheri-tance and molecular markers of clubroot resistance gene in parental lines, F1, F2 and BC1 of non-heading Chinese cabbage were studied through pathogen inoculation at seedling stage and ISSR-PCR. [Result] Clubroot resistance in non-heading Chi-nese cabbage was control ed by a single dominant gene. ISSR molecular markers with Bulk segregant analysis （BSA） found that primer-873 was linked to resistance gene, named CR-873, and the genetic distance between the marker and the resis-tance gene was 9.72 cM. [Conclusion] The results provide references for the molecular marker assisted breeding of non-heading Chinese cabbage.

Role of nitrification inhibitor DMPP(3,4-dimethylpyrazole phosphate) in NO^-_3-N accumulation in greengrocery( Brassica campestris L. ssp. chinensis ) and vegetable soil

The influence of nitrification inhibitor(NI) 3,4 dimethylpyrazole phosphate(DMPP) on nitrate accumulation in greengrocery( Brassica campestris L. ssp. chinensis ) and vegetable soil at surface layer were investigated in field experiments in 2002 and 2003 Results showed that NI DMPP took no significant effect on yields of edible parts of greengrocery, but it could significantly decrease NO - 3 N concentration in greengrocery and in vegetable soil at surface layer. In addition, NI DMPP could reduce the NO - 3 N concentration during the prophase stage of storage.

Genetic linkage map of Brassica campestris L.using AFLP and RAPD markers

A genetic linkage map comprised of 131 loci was constructed with an F 2 population derived from an inter subspecific cross between Brassica campestris L. ssp. chinensis cv. 'aijiaohuang' and ssp. rapifera cv. 'qisihai'. The genetic map included 93 RAPD loci, 36 AFLP loci and 2 morphological loci organized into 10 main linkage groups (LGs) and 2 small groups, covering 1810.9cM with average distance between adjacent markers being approximately 13.8cM. The map is suitable for identification of molecular markers linked to important agronomic traits, QTL analysis, and even for marker assisted selection in breeding programs of Chinese cabbage and turnip.

Nitrogen Dioxide-Induced Responses in Brassica campestris Seedlings: The Role of Hydrogen Peroxide in the Modulation of Antioxidative Level and Induced Resistance

This article investigates the responses of Brassica campestris seedlings to an acute level of nitrogen dioxide （NO2） exposure in a plant growth chamber, and examines whether pretreating plants with hydrogen peroxide （H2O2） will alleviate NO2-caused injury. Twenty-eight-day-old B. campestris plants sprayed with 10 mmol L^-1 H2O2 aqueous solution （corresponding to approximate 1.0 mg H2O2 per single plant） were exposed to different concentrations of NO2 （0.25, 0.5, 1.0, and 2.0 μL L^-1, respectively） for 24 h under controlled environment. To measure the plant biomass, the plants were fumigated with the same NO2 concentrations as mentioned above for 7 h per day （8.00-15.00） for 7 days. As a control, charcoal filtered air alone was applied. Data were collected on plant biomass, total chlorophyll, photosynthetic rate, stomatal conductance, nitrate and nitrate reductase （NR）, antioxidative enzymes, ascorbate （ASA）, and malondialdehyde （MDA）, immediately after exposure. The results showed that exposure to a moderate dose of NO2 （e.g., 0.25 μL L^-1） had a favorable effect on plants, and the dry weight of the above-ground part increased, whereas the exposure to high NO2 concentrations （e.g., 0.5 μL L^-1 or higher） caused a reduction in the plant biomass and the total chlorophyll, when compared with the control. In addition, at 0.5 μL L^-1 or higher NO2 concentrations, prominent increases in the MDA level and superoxide dismutase （SOD） and NR activities were observed. Exposure to 1 μL L^-1 and higher NO2 resulted in necroses appearing on older leaves, and an increase in catalase （CAT） activity, decrease in ASA content, increased accumulation of NO3^-, and reduction in photosynthesis, when compared with the controls. No changes were detected in stomatal conductance under NO2 fumigation. The pretreatment with 10 mmol L^-1 H2O2 alleviated significantly NO2- caused biomass decrease and photosynthetic inhibition when compared with H2O2-untreated plants. Under NO2 fumigation, further induction in SOD and CAT activities occurred in H2O2 treated plants when compared with H2O2- untreated plants. The effect of NO2 on the ASA and MDA contents was also absent in H2O2-treated plants. However, the H2O2 treatment did not alter the nitrate content and NR activity in plants under NO2 fumigation. The H2O2 treatment caused a lower rate of stomatal conductance. Taken together, these data suggest that fumigation with an acute level of NO2 causes oxidative damage to B. campestris seedlings. The H2O2 pretreatment markedly protects plants against NO2 stress and this may be associated with inducible antioxidative level. NO2 fumigation contributes, at least in part, to the enhanced levels of nitrate in B. campestris leaves.

Preliminary Study on Tissue Culture Technique of Brassica campestris L. ssp. chinensis (L.) Makino var. utilis

In order to establish a rapid propagation system for Brassica campestris L. ssp. chinensis var. utilis, the anther and cotyledon-cotyledonary petioles were used as explants to conduct tissue culture research. The results showed that not bloomed flower buds with higher styles than petals were appropriate for anther cul- ture. Moreover, most microspores were at the mid-late uninucleate stage at that time. The pollen germination rates of Brassica campestris L. ssp. chinensis var. u- tills were low and the germination rates in autumn and winter were higher than that in summer. The induction medium of anther callus of Brassica campestris L. ssp. chinensis var. utilis was MS＋1.0 mg/L KT＋1.0 mg/L 2, 4-D＋3% sugar＋6 g/L agar＋ 8% coconut milk and the induction media of adventitious bud were MS＋2.0 mg/L 6-BA＋ 0.5 mg/L NAA＋I.0 g/L activated carbon＋2% sugar＋6 g/L agar or MS＋2.0 mg/L ZT＋ 0.5 mg/L IAA＋0.5 g/L AgNO3＋1.0 g/L activated carbon＋2% sugar＋6 g/L agar. The induction percentage of adventitious bud by anther culture was 36.7%. Browning phenomenon appeared during the culture of adventitious bud and regeneration plant could not be formed. The plant regeneration rate reached 80% when cotyledon- cotyledonary petioles were used as explant.

不结球白菜细胞质雄性不育材料的筛选及其保持系选育

用多种不同基因型的可育不结球白菜(Brassica campestris ssp. chinensis Makino)材料对2个不结球白菜雄性不育株进行授粉,根据F1代群体的育性表现,筛选出细胞质雄性不育株;对16个自交品系的纯度进行调查,各品系筛选出5个或10个典型植株对其株高、开展度、叶长、叶宽、叶柄长、色泽等性状进行测试和比较分析。结果表明,16个品系的纯度均不低于50%;1-5、3-31、2-16、2-61、1-79、华冠4的开展度、株高均较大;聚类结果显示,3-31、1-9、2-61、2-16和华冠4聚在第三类,品系间性状差异较小。1-5、1-79、3-31、2-61、1-26、2-11、2-25和1-98各性状的变异系数均低于30%,一致性好;16个自交品系叶色空间分布较叶柄色集中,说明品系间叶色差异较小;3-31、1-79、1-34-17、2-11、2-16、1-5和华冠4的叶色亮丽。综合分析,1-5、1-79、3-31和2-11色泽好,变异系数小,且纯度高,是选育保持系的优良品系;而华冠4和墩子黄既可以作保持系又可以作父本。3-31和华冠4的植株高大,分别适宜作为保持系和父本,用于选配高产的不结球白菜杂交组合。

镉对小白菜光合作用特性影响的研究

研究表明,微量镉(Cd)(0.01、0.1 mg/L)促进小白菜(Brassica campestris ssp.chinensis)生长,对苏州青的促进作用更明显;高浓度Cd显著抑制地上部生长,对根系生长影响相对较小.Cd降低小白菜叶绿素含量,特别是苏州青降低幅度较大.低浓度Cd对小白菜净光合速率Pn影响不大,高浓度Cd可能是由于非气孔限制而引起Pn降低.Cd降低气孔导度,但高浓度Cd增加胞间CO2浓度.叶绿素荧光测定表明,Cd对小白菜叶片光化学效率Fv/Fm影响不大,而高浓度Cd明显降低光合电子传递量子效率PSⅡ、光化学淬灭系数qP和电子传递速率ETR.Cd增加沪青一号非光化学淬灭系数qNP,而苏州青在高Cd浓度下qNP下降.

白菜核雄性不育两用系AFLP扩增特异片段的克隆及序列分析

利用AFLP技术从白菜核不育两用系"矮脚黄"可育系DNA中得到一个特异扩增片段MF-14.Southern杂交结果证实不育系也存在该片段的同源序列;回收该特异扩增片段并将其克隆到pGEM-TEasy载体进行序列测定.测序结果表明,该片段全长289bp,其碱基组成为A+T=46.02%.与白菜RAPD特异片段S107及其他育性相关基因核苷酸序列比较,同源性均低于50%.表明该片段为一新的序列.

正交设计优化菜薹ISSR反应体系研究

菜薹原产中国,是华南地区重要的特产蔬菜之一。目前,分子标记技术已广泛应用于多种作物研究,但在菜薹上的应用研究刚刚起步。ISSR主要是由单一引物且以重复序列为主要引物序列的PCR标记,其反应条件受模板DNA、Taq DNA聚合酶、Mg2+、dNTP和引物等因素的影响。正交试验设计能明确各因素间的互作效应,建立最优化的反应体系。本研究利用正交试验设计,从Taq DNA聚合酶、dNTP、引物、Mg2+4种因素3个水平对菜薹ISSR反应体系进行了优化,确立了适合菜薹的ISSR反应体系并在7个菜薹品种中进行了验证。在20μl反应体系中,含Taq DNA聚合酶1U、dNTP250μmol/L、引物0.25μmol/L、1×PCRbuffer、Mg2+2.5mmol/L、模板DNA30ng。通过梯度PCR测验,确定了适宜的退火温度。这一体系的建立为今后利用ISSR技术进行菜薹种质资源分类、遗传图谱构建和基因定位奠定了技术基础。

四倍体不结球白菜的诱导及染色体倍性鉴定

用不同浓度秋水仙素处理子叶期不结球白菜生长点对其进行染色体倍性操作,根据形态解剖学、细胞学特征和流式细胞仪进行倍性鉴定.结果表明,浓度为0.2%的秋水仙素处理4次的效果最好,四倍体诱变率为8.42%.与二倍体相比,四倍体植株叶片、花器官、气孔等均表现巨大性;气孔密度和结实率降低;抽薹较晚.用流式细胞仪进行倍性鉴定,对照DNA相对含量为100,疑似株为200,表明是四倍体;疑似株有2个值与对照的比值约为1和2,表明是嵌合体(2x+4x).流式细胞仪鉴定结果与染色体计数法鉴定结果一致,表明流式细胞仪可以较准确地检测不结球白菜突变株倍性.

不同春化时间对不结球白菜现蕾开花的影响

为探求不同品种不结球白菜(Brassica campestris ssp.chinensis Makino)的冬性强弱,找出其适宜的春化时间,以4个不结球白菜品种为试材,在3℃条件下分别对萌动种子春化处理10、15、20、25 d,调查不同春化时间对各品种现蕾开花的影响,综合评价植株现蕾开花早晚及开花期植株形态。结果表明,奶白菜最适春化时间为10 d,青梗白菜最适春化时间为15 d,乌塌菜最适春化时间为20 d,京水菜最适春化时间为25 d。4个不结球白菜品种冬性由弱到强为奶白菜、青梗白菜、乌塌菜、京水菜。

白菜和芜菁Ogura型雄性不育系与保持系的获得及其细胞学观察

通过甘蓝型油菜Ogura细胞质雄性不育材料与白菜、芜菁的种间杂交和连续回交,获得了不育性稳定的白菜、芜菁Ogura细胞质雄性不育系‘新选Ogu28-4’、‘矮脚黄Ogu33-14’和‘耐病Ogu18-4’及其相应的保持系。细胞形态学研究表明:虽然这3个不育系核背景不同,但花药败育时期基本相同,均具有单核败育型的特征;小孢子到单核期后不再向前继续发育,而是迅速退化以至解体,开花前彻底败育;不育系的花药在减数分裂早期绒毡层细胞中已出现液泡,有肥大趋势,而正常花药绒毡层的发育在减数分裂过程中达到高峰,四分体时出现退化迹象,开花前完全解体。不同的眙Ogura细胞质雄性不育系,虽然核背景不同,但花药败育的时期基本相同,说明Ogura CMS胞质互作关系稳定,受核背景影响小。

小白菜耐热性鉴定及其耐热性分析

以68份小白菜为试材,通过田间表型鉴定,筛选出耐热性不同的材料,并对不同耐热性材料的丙二醛含量、叶片质膜透性和脯氨酸含量进行测定。结果表明,通过田间表型鉴定,筛选出5份耐热材料和5份不耐热材料,高温胁迫下,随着时间的延长,耐热材料和不耐热材料的丙二醛含量、叶片质膜透性和脯氨酸含量呈升高的趋势,且两者间差异达显著水平。因此,丙二醛含量、叶片质膜透性和脯氨酸含量可以作为小白菜耐热性鉴定的间接指标。

青菜子叶离体再生体系的建立

以子叶为外植体 ,研究了苗龄、培养基中 Agar浓度、BA与 NAA的组配和添加 Ag NO3、GA3对子叶产生不定芽的影响 .结果表明 ,5～ 9d苗龄的外植体最易诱导出不定芽 ;培养基中 BA浓度是影响不定芽形成的关键 ,BA浓度低于 2 mg/ L,不定芽难以发生 ,BA6mg/ L与 NAA0 .0 5mg/ L的搭配有利于不定芽形成 ;在一定范围内不定芽发生频率随着 Agar浓度的提高而提高 ;培养基中添加 5mg/ LAg NO3,2～ 3mg/ L GA3可以提高不定芽的发生频率 ;在此基础上建立了青菜离体再生体系 ,利用该体系能够获得较高的芽苗再生频率 。