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1.
为揭示睡莲(基部被子植物)的开花特性,探究雄蕊在睡莲花瓣节律性开放过程中的作用.本研究以蓝鸟睡莲(Nymphaea 'Blue Bird')为实验材料,在去雄(摘除雄蕊)后记录花瓣开放角度和萎蔫时间,并于去雄后第6、24、48及72小时测定花瓣的生理生化指标变化.结果 显示,去雄后睡莲花瓣的开放角度小于对照组,在第48小时与对照组开放角度差异最大,达到49.31°,而去雄后花瓣萎蔫的时间与对照组相同,均出现在第72小时;去雄引起了花瓣多项生理生化指标发生变化,其中,含水量在第24小时与72小时显著低于对照组,比对照组分别低0.7%与0.9%;可溶性糖含量变化显著,在第24小时和48小时比对照组分别高出0.48与0.68 mg/g;脯氨酸(Pro)含量在第72小时显著高于对照组;过氧化物酶(POD)活性从第24小时起比对照组显著升高;而丙二醛(MDA)含量则与对照组无明显差异.以上结果说明,去雄导致了睡莲花瓣开放角度及生理状态发生改变,该发现进一步地揭示了睡莲的开花特性,首次证明了雄蕊对于花瓣节律性开放具有调节作用,为花瓣开放闭合及切花保鲜等领域的研究提供了新的思路. 相似文献
2.
Ruimin Chao Chengqiang Xia Caixia Pei Wenjie Huo Qiang Liu Chunxiang Zhang Youshe Ren 《Journal of animal physiology and animal nutrition》2021,105(1):26-34
The objective of this study was to investigate the characteristics of ruminal microbial communities of alpacas (Lama pacos) and sheep (Ovis aries) fed three diets with varying ratios of roughage (corn stalk) to concentrate, 3:7 (LS), 5:5 (MS) and 7:3 (HS). Six alpacas (one-year-old and weighing 29.5 ± 7.1 kg) and six sheep (one-year-old and weighing 27.9 ± 2.7 kg) were used in this study, in a replicated 3 × 3 Latin square experiment. Total protozoa concentration was determined under the microscope; total fungi and methanogens were assessed using quantitative polymerase chain reaction and expressed as a percentage of total bacterial 16S rRNA gene copies; bacterial communities were investigated by targeted 16S rRNA gene (V3–V4 region) sequencing. The percentage of fungi was significantly higher in alpacas than in sheep under the LS diet, while the concentration of protozoa was significantly lower in alpacas under HS, MS and LS diets. The alpha diversity including Shannon, Chao l and ACE indices of bacterial communities was higher in alpacas than in sheep, under the LS diet. A total of 299 genera belonging to 22 phyla were observed in the forestomach of alpaca and sheep, with Bacteroidetes and Firmicutes dominating both animal species. Phyla Armatimonadetes and Fusobacteria, as well as 64 genera, were detected only in alpacas, whereas phyla Acidobacteria and Nitrospira, as well as 44 genera, were found only in sheep. The abundance of cellulolytic bacteria, including Butyrivibrio and Pseudobutyrivibrio, was higher in alpacas than in sheep under all three diets. These differences in the forestomach microbial communities partly explained why alpacas displayed a higher poor-quality roughage digestibility, and a lower methane production. Results also revealed that the adverse effects of high-concentrate diets (70%) were lesser in alpacas than in sheep. 相似文献
3.
试验于1990~1992年在江苏农学院实验农场进行,供试品种(系)为扬麦5号、冀845418和8874.通过在小麦开花期喷施强力增产素,研究其对小麦花后干物质生产和产量的影响。结果表明:喷施强力增产素能延缓花后叶片的衰老,提高叶片叶绿素含量,增强光合功能,扩大花后干物质积累量,具有一定的增粒、增重作用。开花期喷施,可增产6.82%~8.56%,花后20d喷施效应下降,仅增产3.73%。 相似文献
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Comparison of morphology, viability, and function between blood and milk neutrophils from peak lactating goats 下载免费PDF全文
Sui Zhi Tian Chai Ju Chang Chih Chi Chiang Huo Cheng Peh Mu Chiou Huang Jai-Wei Lee Xin Zhao 《Canadian journal of veterinary research》2005,69(1):39-45
The morphological features of blood and milk neutrophils from peak lactating goats were compared using light microscopy, scanning electron microscopy and flow cytometry in order to investigate the cytological changes of neutrophils after migration into the mammary gland. The kinetics of reactive oxygen intermediates (ROI) generation and gelatinase release of blood and milk neutrophils, with or without stimulation of phorbol 12-myristate, 13-acetate ester (PMA), were used to characterize their responses to inflammatory stimuli. Neutrophils isolated from goat milk were highly segmented and contained multi-lobed nuclei. Ultrastructurally, milk neutrophils were more ruffled on the surface compared to blood neutrophils. Approximately 30% of milk neutrophils were undergoing cell death, either necrosis or apoptosis, in contrast to 8% of blood neutrophils. The ROI production of activated milk neutrophils peaked earlier than blood neutrophils, but the duration and the intensity were much less. Neutrophils from both sources augmented the release of gelatinase in response to PMA (1 ng/mL). However, the amount of gelatinase released from milk neutrophils was lower (P < 0.05) than that of blood neutrophils. In summary, more neutrophils become apoptotic and necrotic in the mammary gland, presumably due to spontaneous aging, the process of diapedesis, and the interaction with milk components. Milk neutrophils have impaired functionalities in comparison with blood neutrophils. The information is relevant when studying mammary gland immunity and related diseases, such as mastitis. 相似文献
6.
番木瓜环斑病毒株系的分子生物学方法鉴定 总被引:6,自引:1,他引:6
以PRSV株系特异性引物对PRSV的PRSV126(PRSV日本分离物)、Ys、Vb和Sm等株系进行RT-PCR方法鉴定,引物PR21/PR22能把Ys从Vb和Sm中鉴定出来,PR300/PR301则能把Vb从Ys、Sm和PRSV126中鉴定出来;用限制性内切酶Hae Ⅱ、Sau3A I和Hinf I对PRSV的PRSV126、Ys、Vb和Sm等株系进行单酶切RT-PCR-RFLP分析,Hinf I能把PRSV126与Ys、Vb和Sm鉴别开来,Sau3A I能把Ys与Vb和Sm鉴别开来,Hae Ⅱ则能把Ys与PRSV126、Vb和Sm鉴别开来;以P1/P2为引物,对Vb、Ys和Sm株系进行RT-PCR-RFLP-SSCP分析,结果能一次把三者较好地区别开来。 相似文献
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粉蕉、大蕉和龙牙蕉的AFLP分类研究 总被引:20,自引:0,他引:20
应用AFLP 技术, 对32 个粉蕉、大蕉、龙牙蕉品种进行了遗传多样性分析及分类研究。在分子水平上, 可将供试品种聚为6 个独立群体, 其中包括3 个分别由单一品种组成的群体(群体Ⅳ: 酸大蕉;群体Ⅴ: 孟变; 群体Ⅵ: 千旁培) ; 可以将群体Ⅰ (大蕉) 和群体Ⅱ (粉蕉) 分别划分为3 个品种群, 将群体Ⅲ (龙牙蕉) 划分为2个品种群。参照Simmonds 的形态学分类方法, 研究结果显示粉蕉、大蕉以及龙牙蕉各个品种之间存在丰富的遗传多样性, 将其划分为AAB 或ABB 等类型, 不能反映品种间的亲缘关系; 粉蕉与大蕉两个类群之间遗传距离差异明显, 将其简单的归为ABB 类型是不妥当的。 相似文献
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荔枝品种亲缘关系的AFLP分析 总被引:21,自引:4,他引:21
应用AFLP技术,对39个荔枝品种进行了遗传多样性分析及分类研究。筛选出适于荔枝AFLP分析的最佳引物组合3对,分别为EcoRI AAC+MseI CTG,EcoPd AGC+MseI CAT,EcoRI ACC+Msel CAT。在分子水平上,荔枝品种的遗传多样性并非形态学性状所体现的那样丰富。AFLP分析将39个荔枝品种分成了6组,与传统的以果皮龟裂片隆起类型为分类标准的分类没有一致性。初步建立起荔枝主要栽培品种的分子标记标准图谱。应用AFLP技术对来自两个不同地方的两个荔枝品种(桂味、妃子笑)进行了鉴别。 相似文献