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101.
102.
PEG处理葡萄试管苗生理反应及叶片组织形态研究 总被引:2,自引:0,他引:2
应用不同浓度的聚乙二醇(PEG10000)处理红地球葡萄生根试管苗,在造成一定程度水分亏缺的情况下,观察葡萄试管苗的生理反应和植株生长、叶片形态解剖结构的变化。结果表明:在PEG处理下,葡萄生长发育迟滞,植株节间变短,株高变矮,但发根数量增加,根变长;新生叶片与对照比,叶片小而皱缩,气孔指数降低,上皮细胞排列更紧凑;同时葡萄试管苗脯氨酸的积累和内源ABA迅速增加。说明在一定强度的水分胁迫下,葡萄试管苗叶片的发育向增强其耐旱能力的方向进行,其渗透调节物质的积累是葡萄试管苗对长期水分胁迫的生理反应。 相似文献
103.
干旱胁迫下外源脱落酸对大豆花期生理特性的影响 总被引:3,自引:0,他引:3
以大豆品种绥农14为材料,采用盆栽试验研究了大豆花期干旱胁迫条件下喷施不同浓度外源脱落酸(ABA)对大豆生理特性的影响,并对不同浓度脱落酸的作用效果进行比较。结果表明:与正常供水相比,干旱条件下的大豆叶片过氧化物酶活性、丙二醛含量、可溶性糖含量、游离脯氨酸含量均增加,超氧化物歧化酶活性和叶绿素含量降低,喷施一定浓度外源ABA明显缓解了干旱胁迫下大豆各项生理指标的变化幅度。喷施ABA后1~13 d,4.0 mg.L-1的ABA明显提高了过氧化物酶的活性、1.0 mg.L-1ABA能明显促进超氧化物歧化酶活性升高和可溶性糖含量增加,并能缓解叶绿素含量的降低;3.0 mg.L-1的ABA明显使脯氨酸含量增加;2.0 mg.L-1的ABA对缓解丙二醛积累作用明显。综合分析表明,干旱胁迫下,叶面喷施一定浓度的脱落酸维持了大豆花期叶片的正常生理代谢功能,有效的提高了叶片抗氧化能力和控制了叶片的衰老进程。 相似文献
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Moumita Gangopadhyay Saikat DewanjeeDipjyoti Chakraborty Sabita Bhattacharya 《Industrial Crops and Products》2011,33(2):445-450
The present study describes the role of different exogenous hormones on morphology and plumbagin production in Plumbago indica hairy roots. It was also aimed to conserve elite root clones via synthetic seed technology. Insertion of rolB gene in transformed roots was confirmed by polymerase chain reaction followed by southern blot analysis. Hairy roots were treated with single or in combination of different phytohormones viz. IAA, IBA, 2, 4-D, NAA, BAP, GA3 and ABA. Cultures incubated with GA3 (0.5 mg l−1) yielded highest root growth due to formation of profuse lateral branching while NAA (0.5 mg l−1) treatment caused highest plumbagin accumulation. Cultures incubated with 2, 4-D exhibited highest inhibitory effect in terms of both root growth and plumbagin production. All phytohormones were found to be effective at lower concentration. In combinatorial study, GA3 + NAA (0.5 mg l−1, each) was found optimum for root biomass and plumbagin production at earlier stage of culture. Different combinations of auxins and BAP induced different morphologies ranging from reduction of lateral branching to rapid disorganization of root matrix. The combinations of ABA and selected auxins were not found promising at any of selected concentration. Based on the effect of exogenous hormones on hairy root culture, elite root clones were selected and encapsulated with sodium alginate matrix. Uniform shaped alginate coated synthetic seeds were conserved up to 6 months exhibited high regeneration potential without disturbing plumbagin content. 相似文献
108.
探讨ABA溶液预处理蝴蝶兰类原球茎(PLB)对耐脱水性及生理学基础的效应,本实验观测H2O和ABA溶液分别预处理PLB的脱水成活率及脱水前后的相关生理指标。结果表明,80μmol/L的ABA溶液预处理PLB,显著降低失水速度,极显著提高脱水后成活率。新鲜PLB、H2O或ABA溶液浸泡的PLB三者之间的干物质重量、相对电导率和成活率均无显著差异。ABA溶液预处理能极显著提高PLB可溶性蛋白、热稳定蛋白、可溶性糖和蔗糖含量,明显地降低还原糖含量,也能使PLB的SOD活性极显著提高,POD、CAT活性均极显著降低,但总抗氧化能力极显著提高。所以,ABA溶液短时间处理蝴蝶兰PLB并不能明显改变重量和造成损伤,预处理能提高脱水保护物质含量和总抗氧化能力水平,是增强PLB脱水耐性的基础。 相似文献
109.
The objective of this study is to investigate the effect of different time and rates of boron (B) foliar application on olive (Olea europaea L.) tree's tissue boron concentration, total phenol, chlorophyll, total soluble sugars, and endogenous hormones. A field experiment was conducted during two successive seasons 2010/2011 and 2011/2012 using 20 years old olive trees cv. Frantoio. The trees are grown in sandy soil planted at 5 × 5 m apart under drip irrigation system at the Nuclear Research Center Experimental Farm, Inshas, El-Qaliubiya Governorate, Egypt. Boron was applied foliarly as boric acid at the following rates (0.0, 100, 200, 300, 400, 500 mg L?1) at flower initiation and after 1 and 2 months from flower initiation. Results showed that boron was significantly effective in increasing leaf, bud, and fruit boron concentration. Total phenol concentration in leaves and buds were significantly highest in the control treatment, significantly decreased as the boron application rate increased. Total chlorophyll, chlorophyll a and b, and total soluble sugars significantly increased as the boron application rate increased and the highest increase was achieved at 200 mg L?1 boron concentration rate. Leaf and bud endogenous indole acetic acid (IAA) and abscisic acid (ABA) were highest in the control treatment; they decreased as the boron application rate increased. However, gibberellic acid (GA3) increased in response to boron treatments compared with the control. The maximum increase was observed at 200 mg L?1 boron rate. We concluded that boron is mobile in olive tree as reproductive organs accumulated more boron than vegetative organs. There is evidence that boron is involved in reduction of phenols, increase in fruit set, and in sugar transport. A balance in endogenous hormones (IAA, GA, ABA) concentrations in olive tree has induced the maximum fruit set and yield. 相似文献
110.
MYB转录因子以其含有的保守MYB结构域为特征,是植物转录因子中数量最多的家族之一,广泛参与植物生长发育和代谢的调节。利用生物信息学分析获得222条杨树MYB基因,用实时定量PCR筛选出8条对盐胁迫有强烈应答的基因,研究其在盐、干旱、ABA等非生物胁迫下的表达模式;结果表明:这8条MYB基因虽然在杨树根、茎、叶组织中均有表达,但是在不同胁迫条件和不同组织中的表达水平明显不同。在盐和干旱胁迫条件下,8个基因在根、茎、叶中均被诱导表达,表现为相似的表达模式。在ABA处理条件下,而多数基因无明显应答。说明杨树MYB基因在应答环境变化与激素调节中具有不同的作用,并且在不同组织中的作用有所差异。 相似文献