无菌猕猴桃种子采集方法研究

无菌的猕猴桃种子是猕猴桃胚乳培养、实生苗微嫁接等技术的基础材料,利用消毒剂灭菌是常用的无菌种子采集手段,应用最广泛的消毒剂为升汞(mercuric chloride)和次氯酸钠(NaClO)。为了避免使用消毒剂,该研究提出了一种新的无菌猕猴桃种子采集方法——无菌搅拌法,同时为探索其准确性和应用性,比较了0.2%升汞灭菌20 min、10%次氯酸钠灭菌20 min、无菌搅拌法三种方式采集无菌猕猴桃种子的效果,并对种子萌发和幼苗形成的影响进行了研究。结果表明:无菌搅拌法、0.2%升汞灭菌20 min是稳定有效的无菌猕猴桃采集方式,10%次氯酸钠灭菌20 min的采集效果不稳定;在相同的时间内,无菌搅拌法的种子发芽率最高,为89.90%,但发芽势较低,均可正常成苗; 10%次氯酸钠灭菌20 min的发芽率次之,与无菌搅拌法的种子无显著差异,发芽势和成苗率最高,分别为47.47%和67.86%,且有打破猕猴桃种子休眠的作用,整体作用类似于赤霉素(GA_3)浸种的效果; 0.2%升汞灭菌20 min对猕猴桃种子的萌发有抑制作用,各项指标均显著低于无菌搅拌法种子,且生长缓慢。此外,无菌搅拌法是物理处理,对种子、操作人员、环境均无害。这证实了无菌搅拌法的实用性和优势,发现了次氯酸钠在打破猕猴桃种子休眠方面的作用,为其它同类型果实的无菌种子采集提供了参考。     

临床口腔器械灭菌方法比较

目的:对比压力蒸汽灭菌与化学灭菌剂两种灭菌方法对临床口腔器械的灭菌效果。方法:以金黄色葡萄球菌、白色念珠菌种制备菌悬液,采用悬液定性法进行灭菌实验,以无菌检查法检查口腔器械灭菌效果。结果:有效氯含量2000mg/L的含氯灭菌剂和2%的碱性戊二醛作用一段时间后都不能使手机、吸唾器全部达到无菌;采用135℃的压力蒸汽灭菌10分钟可以使手机、吸唾器全部灭菌。结论:压力蒸汽灭菌比化学灭菌更为可靠,灭活TTV,HBs Ag的效果更好。     

浮萍光周期诱导的探讨──与日本青萍6746对比试验

浮萍从野外生长到室内无菌培养,能在较大的时间范围内用于浮萍的灭菌,以０．０４％ＨｇＣｌ２的灭菌效果最佳。在相同的培养条件下,浮萍比日本青萍６７４６的繁殖和营养生长速度略快,但浮萍对光周期反应不敏感。     

长叶皇冠的组织培养与快速繁殖技术研究

以长叶皇冠短缩茎为外植体进行离体培养,对外植体灭菌方法以及培养基中不同种类和浓度生长调节剂对增殖、生根的影响等进行研究。结果表明:以0.1%的HgCl2为灭菌剂,采用8min+(6～8)min、间歇时间为24h的间歇灭菌法,可获得20%以上的成活无菌外植体;试管苗茎纵切成4份后,接种在1/2MS+6-BA6.0mg·L-1增殖培养基上培养42d,增殖系数可达9.3;在1/2MS+NAA0.2mg·L-1培养基上培养28d后,生根率达100%,平均每株约生根18条;炼苗后移植成活率100%。     

观叶菠萝的快速繁殖

植物名称:松罗铁兰(Tillandsia usneoides)又称观叶菠萝、细叶菠萝,凤梨科、铁兰属。材料类别:芽或无菌芽。培养条件:取植株顶芽进行常规表面灭菌,或者用试管内的无菌芽。均以MS基本培养基为主,于25℃恒温2000 lx光照(12小时)下培养。生长与分化情况:     

盐桦无菌材料的成功获得及其试管苗移栽定植成活的方法

目的:探讨获得盐桦无菌材料的最适灭菌方法和提高移栽定植成活率的关键性技术要点。方法:以新疆濒危植物盐桦当年生休眠枝条为材料,在适宜的培养基上筛选最适灭菌方法,继而以生长85~90d左右的组培试管苗为材料,探讨移植时期、温度、光照、水分、营养对成活率的影响。结果:采用半无菌水表面灭菌 75%酒精30s 0.1%升汞7~10min处理效果最好,污染率为13.3%。盐桦组培试管苗移栽定植中,以4月中旬~5月中旬成活率较高,平均成活率在95%以上。结论:研究筛选获得了盐桦的最适灭菌方法和盐桦组培试管苗移栽定植成活的适宜方法,为工厂化扩繁盐桦苗木创造了条件。     

白及的组织培养

1.植物名称白及[Bletilla striata(Thunb.)Reichb.f.] 2.材料类别白及种子。 3.培养条件采成熟而未裂开的朔果,果皮外用75％乙醇灭菌,在无菌条件下取出种子,播于培养基上。无菌萌发的培养基为Knudson和MS培养基,每升加蔗糖20克,2,4-D1毫克,     

黑节草的组织培养

植物名称:黑节草(Dendrobum candicum) 材料类别:种子在培养基上形成无菌苗后,将无菌苗的幼茎切成0.2—0.5cm的茎段作培养材料。培养条件:培养种子无菌苗是用RM的大量元素为基本培养基,每升附加BA0.2mg,NAA2mg,蔗糖3％,琼脂适量。培养室温度为20—25℃,光强 10001ux,每天光照8小时。生长与分化情况:黑节草的蒴果按常规作表面灭菌后,将蒴果内的种子播种在培养基上,待形成种子无菌苗后,再将无菌苗的幼茎茎段接种在分化     

不同消毒方式对硅橡胶类义齿软衬材料消毒效果的实验研究

目的 对比微波、紫外线和环氧乙烷对Silagum硅橡胶义齿软衬材料的消毒效果.方法 将高温消毒后的软衬硅橡胶试件染菌(白色念珠菌),分别进行不同时间的紫外线、微波、环氧乙烷消毒,消毒后的试件用无菌生理盐水冲洗,无菌玻璃平皿收集冲洗液,接种环将冲洗液接种于沙氏琼脂平板培养基,37℃恒温培养24～48 h观察,菌落计数,评价消毒效果.结果 环氧乙烷(EO浓度600 mg/L)肖毒60 min灭菌率为100％;紫外线(功率40 W、波长253.7 nm、距离1 m)照射40 min可杀灭99％的白色念珠菌、50 min可完全杀灭;微波(800 W V 100％)照射1 min灭菌率为93％,照射2 min灭菌率为100％.结论 三种消毒方法都具有消毒效果,且消毒时间越长消毒效果越好;环氧乙烷、紫外线、微波消毒口腔硅橡胶义齿软衬材料可与高温高压灭菌达到同样的效果,而且方便、有效,是良好的软衬材料的消毒方法.     

用家用高压锅消毒微生物培养基

随着新课程标准的实施,生物学实验课的范围更加广泛。初中教材和高中选修课本中,都出现了制备培养基,培养微生物的实验。实验用具、用材的无菌是微生物学实验成败的关键所在。在有条件的学校,一般都采用高压灭菌锅进行培养基灭菌。但在一些农村中学,由于缺乏相关设备,培养基的消毒灭菌就很难进行。于是,我们设想用家用高压锅代替高压灭菌锅来消毒培养基,并对其效果进行初步的探索。     

鸟巢蕨孢子繁殖技术研究

研究了鸟巢蕨孢子无菌播种和常规播种两种繁殖方法。结果表明,鸟巢蕨无菌播种中孢子萌发率最高可达66.7%,原叶体在固体培养基上培养不能诱导出孢子体,而需经过振荡培养后才能诱导出孢子体;常规播种法更容易诱导出孢子体,每盆播0.02 g孢子时,每克孢子可产生孢子体4 000株以上,比无菌播种操作简便,成本低。因此,孢子常规播种法更适合于鸟巢蕨规模化生产。     

血液或无菌体液培养阳性标本中病原菌检测结果分析

目的：了解血培养（包括血液、无菌体液培养,下同）阳性标本中病原菌的分布及阳性报警时间,为临床及时明确病原菌和正确用药提供参考依据。方法：无菌条件下采集血培养标本注人相应的培养瓶,经仪器扫描后放入血培养仪进行检测,报警后及时进行菌种鉴定和药敏试验。结果：364例阳性报警标本中真阳性标本为176例,其中革兰阳性菌占61．7％,革兰阴性菌占35．0％,真菌占3．3％;188例为假阳性标本,其中革兰阳性菌占54％,革兰阴性菌占41．9％,真菌占4．0％;新生儿科的感染阳性率最高;不同种类病原菌的阳性报警时间多重叠;临床医生经验用药正确或根据药敏结果更换用药的百分比为78．2％。结论：本院引起血液、无菌体液感染的病原菌以革兰阳性细菌为主,病原菌种类较多,存在一定的污染;当新生儿有局部感染时要警惕脓毒血症;单独靠血培养仪报警时间来鉴定区分病原菌与污染菌不一定可靠,及时了解血培养结果及标准药敏结果可以辅助找出感染性疾病的病因,尽早正确合理的使用抗菌药物,从而优化抗菌治疗。     

不同培养方法对甘薯无菌苗生长的影响

试验结果表明,在甘薯组织培养中液体培养不降低无菌苗生长势,对无菌苗生长有一定促进作用,适合于甘薯无菌苗的快速繁殖。液体培养20d比相同条件下固体培养的无菌苗植株高度高出63．16％,经方差分析,差异显著,具有统计学意义;液体培养60d比相同条件下固体培养的无菌苗植株高度,单株叶片数,单叶面积分别高出59．43％,106．70％,49．82％,经方差分析,前两者差异显著,具有统计学意义。     

Reasons for possible failure of inoculation to enhance biodegradation

Pseudomonas strains capable of mineralizing 2,4-dichlorophenol (DCP) and p-nitrophenol (PNP) in culture media were isolated from soil. One DCP-metabolizing strain mineralized 1.0 and 10 micrograms of DCP but not 2.0 to 300 ng/ml in culture. When added to lake water containing 10 micrograms of DCP per ml, the bacterium did not mineralize the compound, and only after 6 days did it cause the degradation of 1.0 microgram of DCP per ml. The organism did not grow or metabolize DCP when inoculated into sterile lake water, but it multiplied in sterile lake water amended with glucose or with DCP and supplemental nutrients. Its population density declined and DCP was not mineralized when the pseudomonad was added to nonsterile sewage, but the bacterium grew in sterile DCP-amended sewage, although not causing appreciable mineralization of the test compound. Addition of the bacterium to nonsterile soil did not result in the mineralization of 10 micrograms of DCP per g, although mineralization was evident if the inoculum was added to sterile soil. A second DCP-utilizing pseudomonad failed to mineralize DCP when added to the surface of sterile soil, although activity was evident if the inoculum was mixed with the soil. A pseudomonad able to mineralize 5.0 micrograms of PNP per ml in culture did not mineralize the compound in sterile or nonsterile lake water. The bacterium destroyed PNP in sterile sewage and enhanced PNP mineralization in nonsterile sewage. When added to the surface of sterile soil, the bacterium mineralized little of the PNP present at 5.0 micrograms/g, but it was active if mixed well with the sterile soil.(ABSTRACT TRUNCATED AT 250 WORDS)     

Reasons for possible failure of inoculation to enhance biodegradation.

Pseudomonas strains capable of mineralizing 2,4-dichlorophenol (DCP) and p-nitrophenol (PNP) in culture media were isolated from soil. One DCP-metabolizing strain mineralized 1.0 and 10 micrograms of DCP but not 2.0 to 300 ng/ml in culture. When added to lake water containing 10 micrograms of DCP per ml, the bacterium did not mineralize the compound, and only after 6 days did it cause the degradation of 1.0 microgram of DCP per ml. The organism did not grow or metabolize DCP when inoculated into sterile lake water, but it multiplied in sterile lake water amended with glucose or with DCP and supplemental nutrients. Its population density declined and DCP was not mineralized when the pseudomonad was added to nonsterile sewage, but the bacterium grew in sterile DCP-amended sewage, although not causing appreciable mineralization of the test compound. Addition of the bacterium to nonsterile soil did not result in the mineralization of 10 micrograms of DCP per g, although mineralization was evident if the inoculum was added to sterile soil. A second DCP-utilizing pseudomonad failed to mineralize DCP when added to the surface of sterile soil, although activity was evident if the inoculum was mixed with the soil. A pseudomonad able to mineralize 5.0 micrograms of PNP per ml in culture did not mineralize the compound in sterile or nonsterile lake water. The bacterium destroyed PNP in sterile sewage and enhanced PNP mineralization in nonsterile sewage. When added to the surface of sterile soil, the bacterium mineralized little of the PNP present at 5.0 micrograms/g, but it was active if mixed well with the sterile soil.(ABSTRACT TRUNCATED AT 250 WORDS)     

水稻雄性不育系及雄性不育突变体筛选研究进展

 为了获得新细胞质源的水稻雄性不育系及雄性不育突变体,以解决目前杂交水稻生产上所面临的不育系来源单一的问题,人们采用了常规育种、诱变育种、组织培养和离体诱变等方法,其中离体筛选尤显其优势性,但也有不少问题有待解决,如能通过离体培养定向地筛选出雄性不育系及雄性不育突变体,无疑将大大提高工作效率。此外,对影响离体筛选雄性不育突变体的因素进行了探讨。     

Re-sorption of organic compounds by roots of Zea mays L. and its consequences in the rhizosphere

The exudation of soluble carbon compounds from Zea mays roots was investigated over a 10 day growth period under sterile and non-sterile solution culture conditions. The results showed that plants grown in sterile static solution culture, where C was allowed to accumulate, released 8 times less C than plants grown under culture conditions in which the solutions were replaced daily. The increased C loss from plant cultures in which exudates were removed daily was attributable to, (a) the reduced potential for root re-sorption of previously lost C, and (b), increasing diffusion gradients between the root and the surrounding bathing solution increasing passive leakage of exudates from the roots. In treatments where C was removed daily from the root-bathing solution, 86% of the total C lost was of a soluble low molecular weight nature, whereas, in sterile and non-sterile static cultures, allowing the accumulation of C over 10 days, this was reduced to 67.5 and 48% respectively. The main C fluxes operating in a solution culture system (efflux and influx of C by both roots and microorganisms) were examined using a computer simulation model to describe movement of soluble sugar-C in both sterile and non-sterile conditions. In sterile static cultures where C was allowed to accumulate in solution over a 10 day growth period, 98% of the C exuded was re-absorbed by the plant. Where C was removed daily from the root-bathing solution this was reduced to 86%. The predicted patterns of C accumulation were similar to those found in the experiments. Simulations showed that the pattern of accumulation and final equilibrium concentrations were dependent on the rate of exudation, the spatial characteristics of exudation, solution volume, root growth rate and the presence of a microbial population. Simulations under non-sterile conditions showed that roots can compete with microorganisms for exudates in solution indicating the possible importance of re-sorption in a soil environment. The results clearly indicate that roots are capable of regulating the net amount of C released into a solution culture with the amount of C collected being highly dependent on the experimental conditions employed. The possible implications of soluble C influx on processes operating within the rhizosphere and in experimental systems is discussed.     

Several nuclear genes control both male sterility and mitochondrial protein synthesis in Nicotiana sylvestris protoclones

Summary Male sterile plants appeared in the progeny of three fertile plants obtained after one cycle of protoplast culture from a fertile botanical line and two androgenetic lines ofNicotiana sylvestris. These plants showed the same foliar and floral abnormalities as the cytoplasmic male sterile (cms) mitochondrial variants obtained after two cycles of culture. We show that male sterility in these plants is controlled by three independent nuclear genes,ms1, ms2 andms3, while no changes can be seen in the mitochondrial genome. However, differences were found between thein organello mitochondrial protein synthesis patterns of male sterile and parent plants. Two reproducible changes were observed: the presence of a new 20 kDa polypeptide and the absence of a 40 kDa one. Such variations were described previously in mitochondrial protein synthesis patterns of the cms lines. Fertile hybrids of male sterile plants showed normal synthesis patterns. The male sterile plants are thus mutated in nuclear genes involved in changes observed in mitochondrial protein synthesis patterns.     

提高光敏感雄性不育水稻花粉单倍体育种效率及不育花粉植株育性转换特点的研究

比较了(光敏s/正常品种)F_1及F_2为供体亲本,对在花药培养时所获得的花粉植株中不育个体/全部花粉植株之比例的影响。结果表明,以F_1为供体亲本,在所获得的二倍体花粉植株(A_1)中,不育株(长日下)约占20%左右;而从F_2分离的不育株为供体亲本,相应的比例为90%左右。对获得不育的花粉植株而言,供体亲本经过F_2的选择,在花粉一代中可以提高育种效率3—4倍。指出,以培育光敏感雄性不育系为目的的花药培养,与一般育种之花药培养采用杂种F_1为供体亲本不同,不仅应对杂种F_2代在长日照条件下进行不育株的选择,而且应在短日照下对这种不育株作育性转换的双重选择。以这种个体作为花药培养的供体亲本,可以大大提高育种效率。 在长日照下表现不育的花粉植株的育性转换具多样性。来自同一组合的不育花粉植株在晚造(短日照)条件下,其花粉有的染色,频率高且稳定;有的虽然可变为染色,但频率不高或不稳定或二者兼有;有些却一直不为Ⅰ-KⅠ染色,或即使染色频率也在10%以下。这一结果与收集全国各地15个光敏核不育系在本昕同期种值条件下的反应十分吻合。这说明通过花药培养,从特定的组合培育出所需要的光敏/光温互作或温敏型的核不育系的可能性是存在的。     

Loss of secreted antibody from transgenic plant tissue cultures due to surface adsorption

The role of surface adsorption in the disappearance of secreted foreign proteins from the medium of transgenic plant cell and organ cultures was investigated. When mouse monoclonal IgG1 was added to sterile plant culture media in glass shake flasks, the antibody concentration declined rapidly demonstrating that antibody was labile in the plant culture environment even in the absence of biomass and proteases. Elution of bound antibody from the surfaces of the flasks indicated that adsorption had contributed to the observed loss of antibody from solution. Antibody retention in sterile plant culture media was improved significantly when protein-resistant polymer coatings were applied to the glass vessels containing the antibody solutions. Pluronic F127 applied at a concentration of 1 mg mL(-1) to a primary dimethyldichlorosilane layer on glass yielded the best results in sterile Murashige and Skoog medium. When this coating was used in shake flasks for culture of transgenic tobacco hairy roots, there was a significant improvement in the accumulation of secreted recombinant antibody in the medium consistent with a reduction in antibody adsorption. Medium antibody levels eventually declined, however, as medium protease concentrations rose rapidly towards the end of the culture period. This work demonstrates that surface adsorption reduces the medium antibody titre observed in transgenic plant tissue cultures.