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1.
为探明东北地区常见野生葱属植物耐旱能力,筛选野生葱属植物耐旱种质资源,本研究以野韭(Allium ramosum L.)、山韭(Allium senescens L.)和蒙古韭(Allium mongolicum Regel)3种葱属植物为材料,采用不同浓度的PEG-6000模拟干旱胁迫,分析其种子萌发期渗透调节物质及酶活性的影响,并结合主成分分析和隶属函数分析比较抗旱性。结果表明:干旱胁迫下,3种葱属植物种子萌发期相对电导率显著升高(P<0.05),丙二醛、脯氨酸、可溶性糖、可溶性蛋白含量及超氧化物歧化酶、过氧化氢酶、过氧化物酶、多酚氧化酶活性均呈现先上升后下降的趋势。3种植物相比,山韭相对电导率最低,渗透调节物质积累量最高,酶活性变化明显。主成分分析表明,4种酶活性之间显示出强相关性。隶属函数分析得出3种植物种子的抗旱性由高到低依次为:山韭 > 野韭 > 蒙古韭。 相似文献
2.
Jssica Borghesi Higor da Silva Ferreira Phelipe Oliveira Favaron Lara Carolina Mario Adriana Raquel de Almeida da Anunciao Franceliusa Delys de Oliveira Rafael Gonalves Hayashi Adriana Caroprezo Morini Maria Angelica Miglino 《Reproduction in domestic animals》2019,54(10):1313-1321
Placenta is formed by a parenchyma rich in extracellular matrix (ECM), and this structure guarantees the proper development of the embryo and placental functioning. Recently, studies have focused on the characterization of ECM in the placenta and foetal membranes of different species. This work aimed to analyse the composition of the ECM and to quantify the types of collagens in its composition. For this, 33 chorioallantoic membranes were used at different gestational ages, which were grouped into five groups. Subsequently, haematoxylin–eosin staining, Masson trichrome and picrosirius were performed for histological analysis. Through the technique of polarized light, it was possible to quantify the total collagen present in the membranes and finally the immunohistochemical technique was performed to verify the presence of collagens and glycoproteins. It was possible to verify that the chorioallantoic membranes have, in all the gestational periods of the initial third of gestation, the same histological structures, being the most significant difference the membrane thickening that occurs gradually during the gestation. However, we notice the appearance of binucleate cells only from group II. In addition, it was verified that a gradual increase of collagen occurs until the group IV, yet from the group V begins to occur a decrease of this protein. In addition, collagen I, collagen III, fibronectin and laminin were present in all membranes. With this, we concluded that the buffalo chorioallantoic membrane presents ECM in constant remodelling at the beginning of gestation and can be used as biomaterial in works on regenerative biology. 相似文献
3.
Kashif Akhtar Weiyu Wang Ahmad Khan Guangxin Ren Sajjad Zaheer Tanveer A. Sial Yongzhong Feng Gaihe Yang 《Soil Use and Management》2019,35(3):526-535
Field experiments were conducted to study soil properties, soil enzymes activities, water use efficiency (WUE) and crop productivity after six years of soya bean straw mulching in the semi‐arid conditions of China. The experiment included four treatments: CK (Control), N (240 kg N ha‐1), H (soya bean straw mulching at half rate 700 kg ha‐1 with 240 kg N ha‐1) and F (soya bean straw mulching at full rate 1,400 kg ha‐1 with 240 kg N ha‐1). Soil organic carbon (SOC), soil labile organic carbon (LOC), soil available N (AN), available P (AP) and enzyme activities were analysed after wheat harvesting in 2016 and 2017. Results show that straw amounts had positive effects on the soil fertility indices being higher for treatment F. The SOC, LOC, AN, AP and enzyme activities (i.e. saccharase, urease and alkaline phosphatase) were in the order of F > H > N > CK. High wheat grain yield and WUE were observed for F treatment. A total of six years mulching along with 240 kg ha‐1 nitrogen fertilizer application is sufficient for wheat yield stability and improving soil properties except urease activities in the semi‐arid condition of China. However, the straw mulching amount should be further studied with minimum nitrogen fertilizer for an environment‐friendly and effective approach for improving the soil biological properties with adequate crop production on a sustainable basis in the semi‐arid region of China. 相似文献
4.
为了解干旱-低温交叉适应对茶树抗寒性的影响,以一年生无性系品种舒茶早茶苗为试验材料,用20%聚乙二醇6000(PEG-6000)模拟干旱预处理,测定低温胁迫过程中茶树半致死温度、丙二醛、抗氧化酶活性、渗透物质和内源激素等部分生理指标的变化。结果表明,经过PEG-6000预处理的茶苗半致死温度LT50明显下降。低温条件下,茶苗叶片丙二醛、抗氧化酶活性、渗透物质和激素含量整体呈上升趋势。低温胁迫第7天时,与对照相比,PEG-6000预处理的茶苗叶片丙二醛含量下降44.6%,SOD、POD酶活分别升高78%和25%,可溶性蛋白、溶性糖含量分别增加44.6%及20.0%;内源激素ABA与SA含量分别提高97.7%和122.0%。干旱可诱导茶树对低温胁迫的交叉适应性,这种交叉适应性与茶树的抗氧化酶活性、渗透物质和内源激素的调节能力有关。 相似文献
5.
本研究以甘草无菌苗为试验材料,采用植物组织培养的方法,分析50 mmol·L-1 NaHCO3 胁迫下外源海藻糖对甘草幼苗生长量、叶绿素含量、渗透调节物质含量、抗氧化保护酶活性和总黄酮含量的影响。结果表明: 50 mmol·L-1 NaHCO3 胁迫显著降低了甘草幼苗的生长量、叶绿体色素含量、K+ 浓度、抗氧化保护酶(SOD、POD、CAT)活性和总黄酮含量,显著提高了丙二醛、脯氨酸和可溶性糖含量以及Na+浓度;施加15 mmol·L-1 海藻糖可显著提高甘草幼苗的生长量,提高叶绿素含量、K+ 浓度和总黄酮含量,降低丙二酸含量、脯氨酸含量、可溶性糖含量和Na+ 浓度,并且提高抗氧化保护酶活性。因此,NaHCO3胁迫下施加外源海藻糖对甘草幼苗生长具有良好的调节作用,可以增强甘草的抗碱能力,促进甘草幼苗生长。本研究为外源海藻糖提高甘草耐碱性和揭示其调控机制提供理论依据。 相似文献
6.
铜过量会导致植物生长、酶系统平衡、细胞亚显微结构、蛋白质合成、核酸代谢等受到不同程度影响,最终,影响人类健康和生态系统平衡。研究表明外源添加物质能够调节铜过量对植物的毒害作用,文章主要归纳分析了外源添加硅(Si)、油菜素内酯(BR)、一氧化氮(NO),以及其他物质对Cu的植物毒害机理调节机制。但目前在离子载体、蛋白质组、基因组等调节机理方面,以及外源添加物质对植物的适用性、外界条件的影响等方面的研究较为缺乏,未来研究可从这些方向进行深入,完善Cu对植物毒害的系统研究。 相似文献
7.
番石榴发育期生物活性物质研究 总被引:1,自引:0,他引:1
番石榴风味独特,营养丰富。本研究以‘珍珠’番石榴和‘水晶’番石榴为试材,研究番石榴果皮和果肉中 生物活性物质含量及其与抗氧化能力关系。结果表明:番石榴果皮和果肉中,‘珍珠’番石榴的总酚、类黄酮、酚酸、 单宁含量均高于‘水晶’番石榴;番石榴的果皮和果肉发育过程中总酚、类黄酮、酚酸、叶绿素及类胡萝卜素含量均 呈下降趋势;番石榴果皮中生物活性物质含量高于果肉,且果皮抗氧化能力高于果肉;在生物活性物质与总抗氧化能 力的相关性方面,总酚含量相关性最高。本研究结果可为番石榴加工产品开发提供理论和实践基础。 相似文献
8.
为了利用植物资源中所具有的杀虫、杀菌、抗病毒和除草等特性的天然活性物质,达到不破坏生态环境、延缓靶标生物抗药性的目的,从黄柏皮、大黄、松脂、芦荟、皂角、苦楝根等多种植物中提取活性物质并混配加工成水剂,对黄瓜白粉病病菌进行毒力测定,并研究了黄瓜、南瓜、西瓜白粉病田间药效试验及安全性评价。结果表明:多种植物活性物质混配剂对黄瓜白粉病的侵染有较强抑制作用,其抑制活性EC_(50)值为5.981 7;对黄瓜、南瓜、西瓜白粉病的防效随着使用浓度的增加而增强,稀释400倍对黄瓜、南瓜和西瓜白粉病的防效分别达75.8%、76.7%和78.1%,施用后对以上瓜类生长安全。 相似文献
9.
The breadmaking quality of wheat is affected by the composition of gluten proteins and the polymerisation of subunits that are synthesised and accumulated in developing wheat grain. The biological mechanisms and time course of these events during grain development are documented, but not widely confirmed. Therefore, the aim of this study was to monitor the accumulation of gluten protein subunits and the size distribution of protein aggregates during grain development. The effect of desiccation on the polymerisation of gluten proteins and the functional properties of gluten were also studied. The results showed that the size of glutenin polymers remained consistently low until yellow ripeness (YR), while it increased during grain desiccation after YR. Hence, this polymerisation process was presumed to be initiated by desiccation. A similar polymerisation event was also observed when premature grains were dried artificially. The composition of gluten proteins, the ratios of glutenin to gliadin and high molecular weight-glutenin subunits to low molecular weight-glutenin subunits, in premature grain after artificial desiccation showed close association with the size of glutenin polymers in artificially dried grain. Functional properties of gluten in these samples were also associated with polymer size after artificial desiccation. 相似文献
10.
[目的]研究南五味子果实多糖和脂溶性物质的抗菌抗氧化作用。[方法]采用水提取法、乙醚索氏提取法,分别提取南五味子果实多糖和脂溶性物质,并对其抗菌作用、抑制羟自由基能力进行研究,并初步鉴定果皮脂溶性物质的化学成分。[结果]南五味子果皮、果肉的脂溶性物质对金黄色葡萄球菌有抗菌作用,抑菌圈分别为19.39、18.28 mm;南五味子果皮、果肉、种子的脂溶性物质对枯草芽孢杆菌有抗菌作用,抑菌圈分别为32.87、19.54、7.52 mm。南五味子多糖、果肉和种子的脂溶性物质,抑制羟自由基能力分别为4 011.48、3 079.01、1 082.66 U/m L。[结论]南五味子果实具有较强的抑菌作用及抑制羟自由基能力。南五味子可作为一种野生水果开发。 相似文献