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141.
‘甬榨5号’是以茎瘤芥菜胞质雄性不育系09-05A为母本,以‘余姚缩头种’高代自交系为父本杂交育成的茎瘤芥新品种。全生长期170 d左右。早中熟。半碎叶,生长势强,株形直立,基部不贴地。瘤茎呈圆形,茎形指数约1.1,鲜样质量413 g左右,加工品质好。耐寒性较强,耐抽薹,产量高,空心率低,抗TuMV病毒病。适宜在浙江省春榨菜产区种植。  相似文献   
142.
A novel and stable cytoplasmic male sterility CMS line of tuber mustard has been bred by subsequent backcrosses for 10 years. Two specific markers atpA and orf220 were cloned and partially characterized in our previous study (Zhang et al. 2003). In this study, two new molecular markers, orf256 and orf305/orf324, have been isolated and identified. The orf256 gene size was found to be 825 bp in CMS line and a 1,357 bp in its maintainer line. Sequence analysis indicated that the orf256 gene was an entire coding sequence and downstream of the cox1 gene. Interestingly, the 906 bp fragment, which contains part of the sequence of orf222, nad5 and orf139 genes, was found to be inserted from the 451st bp of 5′-flank of the 1,357 bp fragment. In the same way, the orf324 gene was isolated from CMS line and orf305 gene from its maintainer line. Both of them are entire coding sequences, upstream from nad3 and rps12 gene, and co-transcribed with the nad3 and rps12 genes. In addition, two molecular markers, orf256 and orf324/orf305, have been successfully converted into the SCAR markers. Subsequently, ORF256, ORF324, ORF305 protein and ORF256-M-431 fragment are predicated to contain signal peptide sequences, and ORF220 was predicated to contain signal anchor sequence. RFLP analysis results revealed that all of the molecular markers exhibited polymorphisms. Northern blot analysis indicated that the expression level of these genes in CMS line is higher than that of the maintainer line. In the mass, all of these genes are expressed lower in the leaf than that of floral organs between the CMS line and its maintainer line. The difference in expression pattern of different mitochondrial specific marker genes suggests that the abundance of mitochondrial proteins is differentially regulated in the organ/tissue development in tuber mustard. Results of this study also provide some novel and useful clues to explore the biological function of these specific marker genes in the tuber mustard.  相似文献   
143.
从种植印度芥菜的盆栽土壤(ρ[Cs~+]为10 mmol·kg-1)中筛选出淡紫拟青霉(A10),通过测试分析A10溶磷、解钾、分泌植物生长素(IAA)类似物及其发酵液对印度芥菜幼苗蓄积Cs~+的影响,研究A10的植物促生特性及其发酵液在印度芥菜蓄积Cs~+过程中的作用,为植物-微生物互作在Cs~+污染环境修复中的应用及其互作机制研究提供实验依据。结果显示:A10对Cs~+的耐受性和富集能力强,ρ(Cs~+)为50~100 mg·L~(-1)时A10的溶磷能力被显著抑制(P0.05);Cs~+处理及外源色氨酸均可显著诱导A10分泌IAA类似物;用1/2 Hoagland营养液稀释A10发酵液后再配制ρ(Cs~+)为25~100 mg·L~(-1)的处理液,用其培养印度芥菜,ρ(Cs~+)为0 mg·L~(-1)(CK)时A10发酵液对印度芥菜幼苗根的生长呈现"低促高抑"的生长素效应,稀释35倍时的促根效果最佳;A10发酵液稀释5、35倍和55倍条件下,ρ(Cs~+)为100 mg·L~(-1)时幼苗地上部Cs~+蓄积量均显著升高,其中稀释35倍时Cs~+蓄积量达最大值,地上部为8.86 mg·g-1DW,地下部为16.76 mg·g-1DW,印度芥菜幼苗蓄积Cs~+与其吸收K+呈显著的负相关性。研究表明,淡紫拟青霉A10具有显著的植物促生特性,A10发酵液有利于提高印度芥菜幼苗对外源Cs~+的蓄积。  相似文献   
144.
土壤养分有效性是影响重金属富集植物的重要因素,为研究炭肥混施下土壤养分缓释特征及芥菜镉富集趋势,试验设置施肥比例(分别为基准施肥量的0、20%、40%、70%、100%,基准施肥量为N 350 kg/hm^2、P_2O5180 kg/hm^2、K_2O 180 kg/hm^2)以及施炭比例(炭肥质量比0、3%、9%)完全组合设计。结果表明:基于Logistic曲线模型模拟炭肥混施下土壤养分缓释特征及镉富集趋势效果较好,均方根误差占实测平均值的3. 29%~8. 37%且R2不小于0. 957 0。炭肥混施下土壤养分高效缓释的施肥比例区间为0. 99%~55. 18%,相比未施炭的有效氮、有效磷最大缓释效率值分别提升49. 17%~90. 00%、13. 25%~37. 35%,高效缓释下土壤养分含量提高17. 38%~40. 93%。镉富集下芥菜生物量通过土壤养分高效缓释增长119. 65%~263. 36%,且地上部相比根部的生物量高效累积最大效率值提高166. 67%~300. 00%,有效氮、有效磷响应区间分别扩大150. 00%、12. 51%,为镉由根部向地上部的转运提供动力基础;芥菜镉含量、富集系数在土壤养分高效缓释区间增长97. 79%~201. 96%。为满足芥菜镉高效富集并兼顾肥料节约,通过模型反算得炭肥混施策略优化为:9%施炭下有效氮、有效磷和有效钾肥的比例分别为60. 58%、61. 32%、21. 48%。  相似文献   
145.
近年来,由于十字花科根肿病在榨菜上扩展蔓延,严重影响其产量,造成巨大的经济损失。本研究筛选生防菌并研究其对榨菜根肿病的控制作用,为其生物防治应用奠定基础。研究发现茎瘤芥等十字花科蔬菜根肿病菌根经过腐烂处理后,休眠孢子的萌发率可到达70%以上。故本文采用稀释法从榨菜根肿病菌根中分离筛选出一株可刺激休眠孢子萌发的菌株PB19。并测定了PB19与根肿病菌互作的最适温度和最适pH,温室盆栽试验和大田小区试验测定菌株PB19对榨菜根肿病的防治效果。最后将纯化后的菌株送至中国食品发酵工业研究院微生物检测中心(FMIC)进行种属鉴定。结果表明:PB19与根肿菌互作的最适温度为20~25℃,最适pH为5.5~7.0。温室盆栽结果显示PB19对榨菜根肿病的防治效果为71.96%。而大田试验结果显示PB19对榨菜根肿病的防治效果为18.04%。FMIC的鉴定结果显示PB19为假单胞菌属Pseudomonas sp.。  相似文献   
146.
In southern Australia, oriental mustard (Sisymbrium orientale) has been controlled successfully by triazine herbicides for several decades. The screening of 40 populations that were collected from the southern grain belt of Australia during 2010 and 2013 for resistance to six different herbicides (glyphosate, diflufenican, imazamox, chlorsulfuron, atrazine and 2,4‐dichlorophenoxyacetic acid) identified two oriental mustard populations as highly resistant to atrazine. Compared to the known oriental mustard‐susceptible populations (S1 and S2), these two resistant populations (P17 and P18) from near Horsham, Victoria, Australia, were 311‐ and 315‐fold resistant to atrazine, as determined by a comparison of the LD50 values. However, there was no resistance to diuron detected in these populations. Sequencing of the chloroplast psbA gene identified a missense mutation of serine 264 to glycine in both herbicide‐resistant oriental mustard populations, which is known to confer high‐level atrazine resistance in other species.  相似文献   
147.
叶用芥菜小孢子培养技术体系的完善及DH系创制   总被引:1,自引:0,他引:1  
以3个优良的地方品种(杂合体)为试材进行游离小孢子培养,对胚诱导、植株再生、倍性分析和单倍体加倍技术进行研究,完善叶用芥菜小孢子培养技术体系,创制优良DH系应用于育种实践中。在小孢子培养中,选取花蕾是小孢子培养成功的关键,花瓣长/花药长为3/4,花药为黄绿色可作为叶用芥菜小孢子培养选取花蕾的形态指标;供试3个品种都获得胚状体,但品种间出胚差异较大,MR-1共45个胚/皿,MR-2共198个胚/皿,MR-3共4个胚/皿;子叶形胚接种于再生培养基上成株率达98%,获得128株再生植株,利用流式细胞仪鉴定出105株双单倍体,自然加倍率为82%,在组培苗期用0.1%的秋水仙素浸泡单倍体植株茎尖1h,加倍率为75%。从DH群体中筛选出4个优良DH系,通过品种比较试验鉴选出1个耐抽薹DH系,4月上旬开始抽薹开花,叶柄宽大肥厚,产量高,适合鲜食加工,可补充当地春淡市场。  相似文献   
148.
Alternatives to soil fumigation are needed for soilborne disease control. The aim of this study was to test anaerobic soil disinfestation (ASD) as an alternative to soil fumigation for control of critical soilborne pathogens in Californian strawberry production. Controlled environment experiments were conducted at 25 and 15 °C to test different materials as carbon sources for ASD using soil inoculated with Verticillium dahliae. Field trials were conducted in three locations comparing ASD with 20 Mg ha?1 rice bran (RB) against fumigated and untreated controls, steam, mustard seed meal and fish emulsion. In ASD‐treated soils, temperature and extent of anaerobic conditions were critical for control of V. dahliae, but multiple carbon inputs reduced inoculum by 80–100%. In field trials, ASD with RB provided control of a number of pathogens, and in three of four trials produced marketable fruit yields equivalent to fumigation. Little weed control benefit from ASD was found. ASD with RB also induced changes in the soil microbiome that persisted through the growing season. When equivalent yields were obtained, net returns above harvest and treatment costs with ASD RB were 92–96% of those with bed fumigation based on average prices over the previous 5 years. ASD can be a viable alternative for control of some soilborne pathogens. Growers are adopting ASD in California strawberry production, but research to determine optimal soil temperatures, anaerobicity thresholds and carbon sources for effective control of specific pathogens is needed.  相似文献   
149.
Pot culture experiment was conducted to evaluate the suitability of extractants and to determine the critical limit of boron (B) in soil and mustard plant in Inceptisols of Varanasi. Twenty-one bulk soil collected from different locations were used for growing mustard. Five extractants, namely hot water, hot 0.01molar (M) calcium chloride (CaCl2), 0.01M CaCl2 + 0.05 M mannitol, 1.0 M ammonium acetate (NH4OAC) and 0.05 M hydrochloric acid (HCl), were assessed by correlating the amount of extractable B in untreated and B fertilizer-treated soil with Bray’s per cent yield, plant tissue B concentration and B uptake by mustard. Similarly, correlation coefficients of the B extracted by different extractants and soil properties were calculated. The suitability of B extracted by different extractants was in the order of hot 0.01M CaCl2 (HCC-B) > hot water (HW-B) > 1.0 M NH4OAC (AA-B) > 0.05M HCl (HA-B) > 0.01M CaCl2 + 0.05M mannitol (CCM-B). The critical limits of extractable B in soil as determined by the graphical procedure were 0.54, 0.60, 0.36, 0.45 and 0.45 mg kg?1 and the statistical procedures were 0.54, 0.60, 0.38, 0.46 and 0.48 mg kg?1 with HW-B, HCC-B, CCM-B, AA-B and HA-B, respectively. Soil containing available B below the critical limit responded to B fertilization.  相似文献   
150.
[目的]优化芥菜腌制发酵工艺,控制腌制芥菜亚硝酸盐含量。[方法]以芥菜为原料,以亚硝酸盐含量、感官评分为指标,采用正交试验设计,优化芥菜腌制发酵工艺的生产方法;以亚硝酸盐含量、亚硝峰峰值的抑制率为指标,采用单因素试验法,确定异抗坏血酸钠、EDTA-2Na、藠头及柠檬酸对亚硝酸盐含量的调控作用。[结果]在乳酸菌接种量5%、食盐添加量5%~7%(取6%)、温度30℃、发酵9 d的工艺条件下,腌制芥菜中亚硝酸盐含量为0.74 mg/kg,远低于国家标准规定的20 mg/kg的标准,所得的腌制芥菜风味可口。异抗坏血酸钠和藠头能有效抑制亚硝峰的峰值及降低成品中亚硝酸盐含量,而柠檬酸和EDTA-2Na仅能有效抑制亚硝峰的峰值,不能有效降低成品中亚硝酸盐含量。[结论]研究可为腌制芥菜的开发利用提供技术支撑。  相似文献   
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