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51.
贵州花魔芋的组织培养及植株再生体系 总被引:1,自引:0,他引:1
为了建立魔芋的组织培养及植株再生体系,促进贵州魔芋产业的发展,以魔芋根状茎为外植体进行组织培养.结果表明:不同外源激素对愈伤组织和根诱导的影响不同,NAA比2,4-D和IBA更有利于愈伤组织的诱导;在改良后的1/2 MS培养基中,KT比6-BA和NAA更有利于根的诱导;愈伤组织诱导培养基为MS+6-BA 2.0mg/L+NAA 0.2mg/L,不定芽诱导培养基为MS+6-BA 4.0mg/L+NAA1.0 mg/L,生根培养基为1/2 MS+KT 0.1mg/L.试验建立了魔芋从外植体到有根苗的组培体系,并移栽组培苗获得了魔芋的小球茎. 相似文献
52.
Summary A spring wheat genotype which produces somatic embryos in vitro, after short and long-term culture, was tested for its ability to sexually transmit this embryogenic trait. Reciprocal crosses were performed between a embryogenic line and a nonembryogenic variety.Immature embryos were cultured on Murashige and Skoog medium plus 2 mg/l 2,4-dichlorophenoxyacetic acid, gelled with 5.5 g/l agarose. Somatic embryogenesis was not expressed in the F1's. In contrast, from several hundred immature embryos of the F2 generation of one cross, 10.7% and 1.6% expressed somatic embryogenesis in short and long-term cultures respectively. These percentages of embryogenic: non-embryogenic fits a model of a few complementary genes. The embryogenic capacity of the F2 genotypes depends on the presence of recessive alleles at these gene loci. The long-term wheat somatic embryogenesis capacity requires a more complex mechanism than the short-term one.Abbreviations CS
Chinese Spring
- Aq
Aquila
- E
Embryogenic
- NE
Nonembryogenic
- SC
Subculture 相似文献
53.
Liza Wittenberg-Voges Sabine BR. Kästner Marja Raekallio Outi M. Vainio Karl Rohn Klaus Hopster 《Veterinary anaesthesia and analgesia》2018,45(2):165-174
Objective
To compare the effects of MK-467 during isoflurane anaesthesia combined with xylazine or dexmedetomidine on global and gastrointestinal perfusion parameters.Study design
Prospective, randomized experimental trial.Animals
A total of 15 warmblood horses.Methods
Horses were divided into two groups for administration of either dexmedetomidine (D) or xylazine (X) for premedication (D: 3.5 μg kg?1; X: 0.5 mg kg?1) and as constant rate infusion during isoflurane anaesthesia (D: 7 μg kg?1 hour?1; X: 1 mg kg?1 hour?1). During anaesthesia, heart rate, mean arterial blood pressure (MAP), systemic vascular resistance index (SVRI) and cardiac index (CI) were measured. Microperfusion of the colon, jejunum and stomach was measured using laser Doppler flowmetry. After 2 hours of stabilization, MK-467 (250 μg kg?1) was administered, and measurements were continued for another 90 minutes. For statistical analysis, the permutation test and Wilcoxon rank-sum test were used (p < 0.05).Results
There were no differences in baseline measurements between groups. The MK-467 bolus resulted in a significant decrease in MAP (D: –58%; X: –48%) and SVRI (D: –68%; X: –65%) lasting longer in group D (90 minutes) compared to group X (60 minutes). While CI increased (D: +31%; X: +35%), microperfusion was reduced in the colon (D: –44%; X: –34%), jejunum (D: –26%; X: –33%) and stomach (D: –37%; X: –35%).Conclusions and clinical relevance
Alpha-2-agonist induced vasoconstriction was reversed by the MK-467 dose used, resulting in hypotension and rise in CI. Gastrointestinal microperfusion decreased, probably as a result of insufficient perfusion pressure. An infusion rate for MK-467 as well as an ideal agonist/antagonist ratio should be determined. 相似文献54.
55.
油葵叶片离体再生体系的建立 总被引:2,自引:1,他引:2
以油葵自交种7B7的无菌苗子叶为诱导不定芽材料,MS培养基为基本培养基,研究油葵子叶组织培养有关影响因子.比较了不同培养基成分、不同碳源、不同附加物对不定芽分化的影响,确定出油葵自交种子叶离体诱导再生芽的最佳培养基:改良MS(MS大量、微量、铁盐、B5有机)+0.5; KNO3+0.05; CH+0.01; 肌醇+3; 葡萄糖+4 mg/L 6-BAP+6~9 mg/L AgNO3+2.6 g/L Phytagel,建立了油葵相对高效的再生体系.为油葵基因转化的研究奠定了基础. 相似文献
56.
利用不同浓度的茉莉酸甲酯(MeJA)对葡萄组培植株进行处理,进而分析其生理及基因表达变化,结果表明MeJA能抑制植株不定根的分化和伸长,诱导根、茎、叶组织中的脱落酸(ABA)含量升高,但降低赤霉素(GA)、生长素(IAA)和细胞分裂素(ZR)的含量,且影响叶片中叶绿素代谢导致褪绿黄化。MeJA能诱导植物体内茉莉酸合成代谢基因表达进而提高内源茉莉酸的含量,诱导ABA合成代谢和信号路径中的基因表达,但是会抑制生长素、赤霉素、细胞分裂素、油菜素内酯合成代谢基因的表达,抑制了与根发育和延伸相关基因VvXET、VvEXPB2、VvEXPA7和VvWUS的表达,进而抑制不定根的发生,导致植物发育缓慢。因此,MeJA通过影响其他激素的合成代谢来调控它们在植物中的含量,导致内源激素不平衡影响植株发育,并调控植株根的发育状态,在不定根发育方面起负向调控作用。 相似文献
57.
百花山葡萄(Vitis amurensis Rupr. var. dissecta)野外仅见一株,是北京市重点保护濒危物种。通过比较不同消毒方法、植物生长调节剂的种类和浓度配比、生根培养基类型,建立百花山葡萄组织培养快速繁殖体系。结果表明,15%的H2O2消毒4 min的效果最好,培养基MS+0.6 mg·L-16-BA+0.3 mg·L-1NAA为愈伤组织最佳诱导培养基,培养基1/2MS+1.0 mg·L-16-BA+0.1 mg·L-1NAA有利于丛生芽的诱导,在诱导不定根时,使用1/2 WPM + 0.2 mg·L-16-BA培养基培养效果最好。采用组培快繁技术,已经获得百花山葡萄完整植株,并于室外移栽成活,为百花山葡萄这一极小种群的保存与繁殖提供了保障。 相似文献
58.
A. Al-Haidar N. Moula A. Leroux F. Farnir S. Deleuze C. Sandersen H. Amory 《Journal of Veterinary Cardiology》2017,19(6):492-501
Introduction
The aim of this study was to establish echocardiographic reference values for the equine species using allometric regression equations based on body weight (BW) and thoracic circumference (TC).Animals
A total of 239 horses or ponies were studied, including 65 warmbloods, 33 Standardbreds, 41 Thoroughbreds, 32 Arabian horses, 28 draft horses, and 40 ponies aged from 1 day to 30 years, weighing from 18 to 890 kg, with no evidence of cardiac disease.Methods
For each horse or pony, a two-dimensional and M-mode echocardiography was performed. Within each breed, the relationships between BW or TC and echocardiographic dimensions were examined using power regression equations. Predictions and their 95% prediction intervals were calculated for the echocardiographic measurements.Results
Within each breed, all echocardiographic measurements showed a significant and positive relationship with a high coefficient of determination for the estimation of the regression equations using BW and TC as the main explanatory variables. Breed-specific power regression equations as well as the 95% prediction intervals were calculated for each echocardiographic measurement as a function of BW and TC.Conclusions
In the future, the body size-corrected and breed-specific echocardiographic reference values calculated in the present study could be used to discriminate between normal and abnormal values in a given animal. 相似文献59.
不同LED光源下培养的马铃薯组培苗在形态特征上差异明显,为探索这种差异是否会对其移栽后产生进一步影响,试验研究了100%红光(R)、100%蓝光(B)、100%绿光(G)、75%红光+25%蓝光(RB)、45%红光+35%蓝光+20%绿光(RBG)和100%白光(CK)6种光谱下培养4周的马铃薯组培苗温室移栽后植株的生长和结薯情况。试验结果表明,B处理的马铃薯组培苗移栽后缓苗期叶绿素荧光参数Fv/Fm和qP、结薯前期SPAD值及结薯期各器官生物量均始终高于CK和其他处理,且该处理下最大薯的干鲜重和有效微型薯占比分别较CK提高45.66%、45.09%和10.93%。R处理的组培苗移栽后结薯期地上部生物量显著高于CK,单株结薯数目提高29.60%,但有效微型薯占比较CK降低63.97%。G处理的组培苗移栽后生长和结薯指标均表现最差。组合光谱RB和RBG处理的组培苗移栽后的生长指标和微型薯产量及产量构成指标均与CK无显著差异。因此,单色红、蓝、绿光谱处理对马铃薯组培苗的影响会持续至其移栽后植株幼苗生长,甚至结薯期,组合光谱RB和RBG则不会。在马铃薯组培苗生产上,单色蓝光和单色红光作为照明光源具有潜在的应用价值,组合光谱RB和RBG可作为白色光源的替代光源。 相似文献
60.
Effect of urea supplementation on performance and safety in diets of Dorper crossbred sheep 下载免费PDF全文
B. Wang T. Ma K.‐D. Deng C.‐G. Jiang Q.‐Y. Diao 《Journal of animal physiology and animal nutrition》2016,100(5):902-910
This study was conducted to evaluate the efficacy and safety of dietary urea in sheep rations having a 50:50 concentrate:roughage ratio. Sixty‐four Dorper × thin‐tailed Han crossbred ram lambs with an average body weight of 30.8 (±0.02) kg were randomly divided into four groups of 16 sheep each, and each group was fed one of the following diets: a basal diet (CON), or CON supplemented with 0.5% (0.5UTM), 1.5% (1.5UTM) or 2.5% (2.5UTM) urea. Growth performance, carcass characteristics, non‐carcass offals, meat quality and peptic tissue lesions were assayed. The average daily weight gains for CON, 0.5UTM, 1.5UTM and 2.5UTM were 216, 218, 200 and 170 g, respectively, with the CON and 0.5UTM groups higher than 2.5UTM group (p < 0.05). Sheep from the 2.5UTM treatment had a significantly lower dry matter intake (1.29 kg/day) than those from the CON and 0.5UTM treatments (1.42 and 1.43 kg/day, p < 0.05), and the feed conversion ratio in the 2.5UTM group was the highest (p < 0.05). Carcass characteristics, including shrunk body weight, empty body weight, hot carcass weight, dress percentage, and the absolute or relative weight (% body weight) of heart, liver, spleen, lung and kidney, were not altered by the treatments (p > 0.05). The muscular pH of 2.5UTM was higher than that of CON (5.68 vs. 5.52, p < 0.05), and shear force in 0.5UTM was lower compared with CON and 2.5UTM (p < 0.05). The anatomical structure lesions in kidneys became more serious with the increasing dietary urea concentrations, with the 2.5UTM animals showing the most severe lesions compared with CON animals. Therefore, supplementary urea as a non‐protein nitrogen source for sheep should not exceed 1.5% of ration having a 50:50 concentrate:roughage ratio to ensure efficacy and safety. 相似文献