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151.
蓝花大叶醉鱼草组培快速繁殖的研究   总被引:3,自引:0,他引:3  
通过蓝花大叶醉鱼组培快繁的试验,研究了对外植体的不同取材部位及不同激素种类、浓度对芽诱导及培殖的影响。结果表明:采用母株基部的茎段作外植体诱导率高,增殖系数大,在做不同激素的比较中,生长素起着决定因素。同时,筛选出最佳分化培养基MS+6-BA1.0mg/L+IBA0.05mg/L或MS+6-BA1.0mg/L+NAA0.5mg/L并对蓝花大叶醉鱼草组培中的一些问题进行了讨论。  相似文献   
152.
用组织培养法保存、增殖桑黄化型萎缩病病原的研究   总被引:2,自引:0,他引:2  
取岛桑(MorusacidosaGriff)苗茎尖进行组培脱毒,昆虫介体接种病原,继代培养,获得无休眠期的标准桑黄化型萎缩病株和病原类菌原体驯化株。通过对MS培养基成分的调节,可以批量繁殖病株和类菌原体。  相似文献   
153.
梨幼果表皮果点形成的组织解剖观察   总被引:1,自引:0,他引:1  
俞宏  贾湘汴 《果树学报》2002,19(1):62-63
梨幼果期皮层细胞组织具有荧光物质,采用活组织切片和荧光显微观察的方法,研究了梨幼果表皮气孔转变为果点过程中,外部形态和内部细胞结构的变化,并根据皮孔细胞组织生长发育的特点,提出了栽培中减小果点形成的有效措施。  相似文献   
154.
甜橙(Citrus sinensis)茎段在MS+KT 1.5mg/L+2.4—D 1.0mg/L培养基上形成的愈伤组织是由皮层与韧皮部薄壁细胞发生的。愈伤组织在MS+BA2.0mg/L+NAAO.2mg/L培养基上分化出丛芽,去掉NAA后有利于丛芽的生长。甜橙试管苗完整叶片在MS+BA1.0mg/L+NAA0.2mg/L培养基上培养15天后,出现叶面生芽。这种芽由叶脉维管束薄壁细胞。或维管束附近的叶肉细胞分裂后直接分化而成。叶面生芽主要分布在叶的主脉或侧脉处。  相似文献   
155.
花叶芋(Caladium bicolor)组织培养一步成苗研究   总被引:5,自引:0,他引:5  
花叶芋外植体在添加NAA0.5—1 ppm和BA1.5—3.5ppm的改良MS培养液内的脱脂棉载体上,先暗培养20d左右,再转入光照黑暗交替培养,不经继代即可在45d内分化出大量的再生植株。应用经改进的无土栽培方法过渡移栽试管苗,缓苗期短,一般在24h内即可恢复生长,而且后期苗的长势也很健壮。花叶芋组织培养的一步成苗法比常规的组培繁殖程序缩短了近两倍的时间,从而提高了效率,加快了花叶芋的繁殖。  相似文献   
156.
以红叶椿幼嫩茎尖和茎段作为外植体材料,筛选各个阶段的培养基配方,研究红叶椿的快速繁殖技术.结果表明:MS+6-BA1.5+NAA0.05对茎尖和茎段的诱导效果最好; MS+6-BA1.0为继代培养基的适宜配方; 1/2MS+IBA1.0生根效果良好.  相似文献   
157.
AIM: To compare 2 environments, the subrenal capsule and oral submucosa, for producing well-formed teeth from mouse tooth germs and for exploring the ideal environment for tooth regeneration. METHODS: Two groups were set up. Group A was transplanted with the mouse embronic day (ED) 14.5 first mandibular molar tooth germs into the subrenal capsule, while group B was transplanted with the ED14.5 first mandibular molar tooth germs into the oral submucosa. After 3 weeks and 4 weeks, the host mice were sacrificed, and the transplanted explants were evaluated with morphologic observation, histological structures, hardness and elastictic modulus tests, and chemical compositions. RESULTS: (1) The explants isolated from both environments showed the tooth-like structures, but as to the group B, the crown was smaller, and the shape of the cusps was not significant. (2) HE staining showed that the dentin and enamel in group A were thicker than those in group B in which the ameloblasts and odontoblasts were differentiated not very well. (3) In the test of enamel hardness, only the hardness of 4 weeks in group B was lower than normal mouse tooth. In the test of enamel modulus, the elastic modulus of enamel in 3 weeks of group A was slightly lower than normal mouse tooth, but the difference was not significant.The elastic modulus of enamel in 4 weeks of group A and group B was significantly lower than normal mouse tooth and 3 weeks of group B. The hardness and elastic modulus of dentin in 3 groups was not significant. (4) Raman spectroscopy showed 2 groups grew in harmony in general, they all had the largest peak in the point of 961 cm-1, but the 3 weeks of group B had an obvious peak in the point of 2 947 cm-1. CONCLUSION: For the development of ED14.5 tooth germs, we obtain almost the whole tooth in subrenal capsule transplantation after 3 or 4 weeks. The buccal submucosa environment still has a certain influence on the tooth germ development, although there are some differences about the tooth development between this environment and subrenal capsule environment.  相似文献   
158.
耿莉  周洁 《安徽农业科学》2005,33(12):2404-2405
介绍了近年来我国沙棘组培的研究状况,探讨了沙棘组培中存在褐化等问题的原因及解决途径。  相似文献   
159.
AIM:To observe the effect of intravitreal injection of pirenzepine on form-deprivation myopia in chicks. METHODS:Forty-one day old chicks were randomly divided into 4 groups:normal control group, form deprivation group, vehicle control group and pirenzepine injection group. The right eyes of all chicks were used as experimental eyes. The deprived eyes in vehicle control group and pirenzepine injection group received daily intravitreal injection of vehicle control solution(0.01 mol/L PBS) and pirenzepine(1%in PBS), respectively. Optical examinations such as refraction, axial length and equatorial diameter were made at the end of the 5th day. The mRNA and protein levels of matrix metalloproteinase 2(MMP-2) and tissue inhibitor of metalloproteinase-2(TIMP-2), and the activity of MMP-2 were detected by RT-PCR, Western blotting and zymography analysis,respectively. RESULTS:Refraction, axial length and equatorial diameter of the eyes in pirenzepine injection group were significantly lower than those in form deprivation group and vehicle control group(P<0.05), but those were higher(P<0.05) and the eyes were relatively myopic as compared with normal control group. The mRNA expression, protein le vels and activity of MMP-2 in pirenzepine group were significantly higher than those in normal control group(P<0.01), and were significantly lower than those in form deprivation group and vehicle control group(P<0.01, P<0.01). The mRNA and protein levels of TIMP-2 in pirenzepine group were significantly lower than those in normal control group(P<0.01), and was significantly higher than those in form deprivation group and vehicle control group(P<0.01, P<0.01). CONCLUSION:Intravitreal injection of pirenzepine may partly prevent form-deprivation myopia by modulating the expression of MMP-2 and TIMP-2 in the fibrous layer of sclera.  相似文献   
160.
克服植物组织培养中内生菌污染的研究   总被引:4,自引:0,他引:4  
组织培养中内生菌污染普遍,严重影响组织培养和工厂化育苗。文章在查阅大量文献基础上,探讨内生菌污染产生的原因,分析控制内生菌污染的有效措施。  相似文献   
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