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51.
【目的】农杆菌介导的辣椒遗传转化较为困难,至今仍未建立高效转化体系。绿色荧光蛋白(GFP)基因是植物遗传转化中常用的报告基因,以GFP为报告基因,优化农杆菌介导的辣椒遗传转化体系。【方法】利用GFP表达系统,统计3个辣椒品种(‘HP’‘8214’和‘L55’)中3种不同外植体(子叶、下胚轴和Flamingo-bill外植体)的不定芽分化率、不定根分化率与荧光阳性率,探究农杆菌侵染浓度、侵染时间、预培养时间和共培养时间等因素对不定芽、不定根分化率及荧光阳性率的影响。【结果】3个辣椒品种的Flamingo-bill外植体不定芽分化率均显著高于下胚轴与子叶外植体,其中‘L55’ Flamingo-bill外植体的不定芽分化率最高、达77.59%,故选用‘L55’ Flamingo-bill外植体进行后续研究。4种农杆菌不同侵染浓度和时间组合下,‘L55’Flamingo-bill外植体均可产生不定芽、不定根及表达GFP的愈伤组织,当农杆菌侵染浓度为OD600=0.05,侵染时间为30 min时,不定芽分化率和荧光阳性率最高,分别达48.39%、4.84%。在6种不同预培... 相似文献
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人参组织培养的多因子正交试验研究 总被引:9,自引:0,他引:9
采用L9(34)正交设计分析比较了2.4-D,BA,NAA,KT 4种激素浓度及其组合对人参组织培养的影响。经直观分析、方差分析和多重比较进行综合评价,确定人参愈伤组织诱导的最优培养基为MS 2.4-D3 mg/L BA 0.5 mg/L NAA 0.5 mg/L KT 0.5 mg/L,人参愈伤组织生长的最优培养基为MS 2.4-D 3 mg/L KT 1 mg/L,人参不定芽发生的最优培养基为MS BA 1 mg/L。 相似文献
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在可控环境下,以有糖培养为对照,对中黄13、中黄25和鑫豆1号三个大豆品种进行了无糖培养试验,探讨了三个品种的组培苗的生长差异和根系活力差异.结果表明,生根培养21 d后,有糖培养处理的大豆组培苗的叶片部分出现黄化现象,无糖培养条件下三种大豆组培苗生长健康,叶色浓绿,生根率均为100%(高于有糖培养),中黄25的根鲜重与根长指标达到最大值,分别为1.02 g和481.6 cm,鑫豆1号的根系活力最高,达到78.62 UTTC·g-1FW·h-1,中黄13与鑫豆1号的根系活力与其有糖培养处理相比差异显著.因此,无糖培养提高了大豆组培苗对环境的适应能力,促进了组培苗的生长发育. 相似文献
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超级稻离体再生培养条件的优化 总被引:1,自引:0,他引:1
以超级稻品种两优培九成熟胚为外植体,研究了外源激素和化学试剂对超级稻离体再生培养的影响.结果表明,成熟胚在MS 2,4-D2mg/L KT1mg/L培养基上,愈伤组织诱导率达94%;愈伤组织在MS 6-BA2mg/L KT1mg/L NAA0.5mg/L培养基上,分化率为76.66%;当分化培养基中添加5mmol/LCuSO4,愈伤组织生长旺盛,分化率提高,可达86.66%. 相似文献
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为探明益生菌能否增强新城疫(newcastle disease,ND)疫苗局部黏膜组织的免疫效果,雏鸡分别于ND疫苗免疫后第0,7,14,21天及新城疫病毒(newcastle disease virus,NDV)攻击7d后或死亡前,采用免疫组织化学方法测定盲肠扁桃体、哈德氏腺和十二指肠派伊尔结的IgA,IgM,IgG抗体生成细胞数量的动态变化.结果发现:益生菌协同ND疫苗组雏鸡局部黏膜的IgA,IgM,IgG抗体生成细胞数量分别在免疫后7d明显高于ND疫苗单独免疫雏鸡(P<0.05);NDV攻击后,益生菌ND疫苗免疫雏鸡的局部黏膜组织抗体生成细胞数量无统计学差异(P>0.05),表明益生菌是疫苗的理想佐剂之一. 相似文献
57.
Régis Moreau Sadasivam J. Kaushik Konrad Dabrowski 《Fish physiology and biochemistry》1996,15(5):431-438
A study was conducted to evaluate tissue storage and mobilisation of L-ascorbic acid (AA) in the Siberian sturgeon (Acipenser baeri) fed three different experimental diets. The three treatments consisted of a diet devoid of vitamin C (diet A0) and two diets supplemented with equivalent of 300 mg AA kg–1 in the form of either silicone-coated ascorbic acid (diet SC) or of ascorbyl-2-polyphosphate (diet AP). During the first phase (4 months) of the trial, six batches of 130 Siberian sturgeon (initial body weight: 25.5±0.5 g) each were fed one of the three diets in duplicate. During the second phase (3 months), fish from groups SC and AP were switched to diet A0 and those fed diet A0 during the first phase were switched to diet SC. Irrespective of the dietary treatment, growth rates were not significantly different from each other. At the end of phase I, in all tissues studied, total ascorbic acid (TAA) concentrations were higher in Siberian sturgeon fed diet AP than in the other two groups. During phase II, tissue ascorbate depletion was also higher in the AP group than in the other two groups. Transfer of the AA-free diet fed group onto a diet supplemented with 300 mg AA kg–1 (diet SC) led to a slight increase in the TAA concentrations in all tissues. Blood plasma tyrosine concentrations were not significantly different between the three groups. Whole-body collagen levels were affected by dietary AA levels or forms at the end of phase I; the differences were not significant at the end of phase II. Muscle collagen levels were slightly affected. L-Gulonolactone oxidase activity was found in the kidney of Siberian sturgeon, but not in the liver. The ascorbyl-2-polyphosphate appears to be either better utilised by Siberian sturgeon, like in many other teleosts, or more stable than the silicone-coated AA during food processing and storage. Presence of L-gulonolactone oxidase activity in Siberian sturgeon kidney combined with the absence of gross scorbutic signs in AA-free diet fed groups expressing very good growth rates suggested no need of dietary AA byA. baeri. 相似文献
58.
A. F. A. El-Mowafi A. Maage M. Lorentzen E. I. Hassanein & K. Julshamn 《Aquaculture Nutrition》1997,3(2):73-80
Two groups of Atlantic salmon post-smolts previously fed diets either unsupplemented or supplemented with Zn, Fe, Cu and Mn were fasted for 6 weeks in order to study the reliability of tissue indicators of element status during fasting. The fish were weighed at 2-week intervals and samples of whole fish liver, vertebrae, serum and eyes were taken for analyses of elements by atomic absorption spectrometry.
Body weight, per cent dry matter, condition factor and haematocrit values decreased during the fasting period. The concentration of elements in whole body remained constant, indicating that whole body is a stable indicator of element status during fasting. Other tissues seemed to be more sensitive (i.e. hepatic Fe concentration and vertebrae Zn and Mn concentrations). The serum concentrations of the elements generally decreased during fasting, especially for P and Zn. Element concentrations in whole body and most tissues during fasting were generally more dependent upon initial element status than on the fasting itself.
Care should be taken in drawing conclusions about the element status of fish based solely upon the examination of serum concentrations, and more than one tissue indicator should be used in the establishment of the element status of fish. 相似文献
Body weight, per cent dry matter, condition factor and haematocrit values decreased during the fasting period. The concentration of elements in whole body remained constant, indicating that whole body is a stable indicator of element status during fasting. Other tissues seemed to be more sensitive (i.e. hepatic Fe concentration and vertebrae Zn and Mn concentrations). The serum concentrations of the elements generally decreased during fasting, especially for P and Zn. Element concentrations in whole body and most tissues during fasting were generally more dependent upon initial element status than on the fasting itself.
Care should be taken in drawing conclusions about the element status of fish based solely upon the examination of serum concentrations, and more than one tissue indicator should be used in the establishment of the element status of fish. 相似文献
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本文为探索湛江近海海域裸体方格星虫的消化系统特点,以湛江近海海域裸体方格星虫为材料,对其消化道的形态和组织学进行了切片剖析。结果表明,裸体方格星虫消化系统由口、咽、食道、肠、直肠、盲肠和肛门等组成;在直肠上附有直肠盲囊,其消化道约为体长的2.5倍,肠道通过3个回折及螺旋缠绕形成肠索;消化道管壁由内向外分为黏膜层、黏膜下层和浆膜层,黏膜层有大量的皱褶,没有连续肌肉层,而黏膜下层由结缔组织组成,含有肌纤维和血管神经等;裸体方格星虫消化道有发达的纤毛,直肠盲囊连接于直肠末端,里面充满黄色液体。 相似文献