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1.
橄榄总多酚含量及多酚氧化酶活性与组培褐变关系的研究 总被引：1，自引：1，他引：0
摘要：本文采集了不同月份下橄榄的不同组织部位,包括老叶、成熟叶、嫩叶、叶柄、幼嫩茎段和去皮的幼嫩茎段、橄榄果实的胚等9个不同部位;研究了这些样品中总多酚含量、多酚氧化酶（PPO）活性和组织培养褐变的关系。研究发现三月份橄榄各部位的总酚含量、PPO活性和褐变率都较低;特别是去皮的幼嫩茎段具有最低的总酚含量和PPO活性, 在组培过程中褐变程度也最低,更易诱导出愈伤组织,是橄榄组织培养过程中选择的理想外植体。实验结果表明,橄榄外植体的褐变是受到酚类物质的含量和PPO的活性影响的,多酚含量与PPO活性越高,越容易引起外植体褐变。 相似文献
2.
Thitima Wongsheree Saichol Ketsa Wouter G. van Doorn 《Postharvest Biology and Technology》2009,51(1):91-96
Leaves of lemon basil (Ocimum × citriodourum) were stored in sealed polyethylene bags at 4 °C and 12 °C. At 4 °C, leaf browning, the visible symptom of chilling injury, occurred earlier and was more severe in mature leaves than in young leaves. No positive correlation was found, when comparing young and mature leaves stored at 4 °C, between browning and either substrate levels (free phenolics) or the activities of peroxidase or catechol oxidase, which might catalyse these reactions. The levels of saturated and unsaturated fatty acids differed only slightly and were not correlated with chilling injury. Compared to young leaves, mature ones showed higher lipoxygenase activity throughout the period of low temperature storage. This might indicate more degradation of membrane unsaturated fatty acids. In addition, mature leaves exhibited lower catalase activity than young ones. This suggests lower protection against membrane oxidation in mature leaves. The data thus suggest a correlation between lipoxygenase activity, antioxidant defense, and chilling injury. 相似文献
3.
移栽期低温强光对烤烟新生叶和成熟叶PSⅡ功能的影响 总被引：1，自引：0，他引：1
为探究低温强光对移栽期烤烟幼苗不同生长阶段叶片的胁迫机制,利用人工模拟移栽期低温强光环境的方法,研究了由温室弱光环境转移到低温高光环境下烤烟幼苗新生叶和成熟叶的快相叶绿素荧光动力学曲线的变化情况。结果表明:烤烟幼苗新生叶的光合性能指数PIABS显著低于成熟叶,而PSⅡ最大光合效率Fv/Fm值虽低于成熟叶,但差异不显著;在低温高光下新生叶片Fv/Fm和PIABS的降低幅度也明显低于成熟叶,说明在低温强光下新生叶更容易发生光抑制现象。新生叶J点和I点的相对可变荧光(V_J和V_I)均明显高于成熟叶,即新生叶PSⅡ受体侧的电子传递速率明显低于成熟叶,且在低温高光下新生叶的V_J增加幅度大于成熟叶,即低温强光加剧了新生叶PSⅡ受体侧电子由QA向QB传递的抑制程度,但新生叶的V_I增加幅度却较成熟叶小,说明低温强光对烤烟幼苗新生叶QB向PQ的电子传递影响较小。新生叶的K点和L点的相对可变荧光(V_K和V_L)明显高于成熟叶,并且低温高光处理下新生叶V_K和V_L的增加幅度明显大于成熟叶,说明低温高光处理对新生叶放氧复合体和类囊体膜结构的伤害程度更大。总之,移栽期低温强光胁迫对烤烟幼苗新生叶PSⅡ功能的伤害程度明显大于成熟叶,这与新生叶光化学活性、电子传递速率以及OEC对低温强光胁迫更为敏感有关。 相似文献
4.
G. Economou O. Tzakou A. Gani A. Yannitsaros D. Bilalis 《Journal of Agronomy and Crop Science》2002,188(4):248-253
The allelopathic influence of four plant tissues of Conyza albida (stems, leaves and inflorescences) on oat growth were investigated using in vivo tests. Oat growth (fresh and dry weights of above and underground parts) was inhibited from phytotoxic activity of upper leaves and inflorescence tissues of C. albida in pot studies. The inhibition was significantly higher than in the other tissues studied. The inhibiting action of crude extracts and volatile compounds from young plants (rosette) and mature plants were examined using two bioassay methods: (a) seed germination and radicle growth of oat and (b) fresh weight of duckweed plants. Both bioassayed species exhibited greater phytotoxic response from the young plants, collected in winter, than from the mature ones. 相似文献
5.
The effect of salt stress on salicylic acid (SA) synthesis was investigated parallel with the induction of antioxidant enzymes in young maize plants. Two-week-old maize plants grown in hydroponic solution were treated with 50 or 100 m m NaCl for 7 days. Antioxidant enzyme activities, and the SA and o -hydroxy-cinnamic acid (oHCA) levels were measured on the 3rd and 7th day of treatment and after 4 days of recovery. Ascorbate peroxidase activity increased in the leaves, but changes in guaiacol peroxidase activity only could be detected in the roots after 7 days. Glutathione reductase activity increased both in the leaves and in the roots after the 3rd day of 100 m m NaCl treatment. Free SA only increased during recovery in the leaves and roots. In the leaves of plants treated with 100 m m NaCl, a slight increase was observed in the free oHCA level, which rose dramatically after recovery, while in the roots an increase could only be seen after recovery. These results suggest that oHCA may serve not only as a precursor of SA but may also have an antioxidant role during salt stress and recovery. 相似文献
6.
腺苷二磷酸葡萄糖焦磷酸化酶活性对小麦K、V、T型不育系育性及籽粒形成的影响 总被引：2，自引：0，他引：2
为进一步探寻小麦不育系的不育机制和籽粒不饱满的生理机制,以冀5418核基因为遗传背景,对同核异质K、V、T型不育系叶片、幼穗和籽粒中的腺苷二磷酸葡萄糖焦磷酸化酶(ADP-glucose pyrophosphorylase, AGPase)活性和淀粉积累量进行了动态观测,并与各自的保持系进行了比较。在雌雄蕊原基分化期, 不育系幼穗中AGPase活性较保持系高9.33~27.94 μmol g-1 FW h−1, 差异达极显著水平(F=133.81, P<0.0001); 而在四分体期, 不育系幼穗中该酶活性极显著低于保持系(F=13.97~75.20, P<0.0001),差异为4.27~7.44 μmol g-1 FW h−1。雌雄蕊原基分化期至四分体时期,不育系叶片中AGPase活性较保持系高7.39~80.77 μmol g-1 FW h−1,差异极显著(F=135.76~5454.28,P<0.0001)。不育系强、弱势粒中总淀粉、直链淀粉和支链淀粉积累量、AGPase平均活性、淀粉含量及直/支比均极显著低于保持系,且这些指标均表现为强势粒显著高于弱势粒。Logistic方程显示,不育系籽粒淀粉积累量的减少主要由淀粉积累速率降低引起;籽粒AGPase活性与淀粉积累速率显著或极显著正相关(r=0.4460~0.7150, P=0.0004~0.0487);灌浆期, 叶片中AGPase活性与光合速率呈负相关(r=−0.28634, P=0.2823)。因此,雄性不育的可能原因是雌雄蕊原基分化期幼穗和叶片中AGPase活性高,幼穗发育所需能量供应不足;而四分体期幼穗AGPase活性低,影响花粉中淀粉积累。不育系对籽粒AGPase活性具有明显的不良胞质效应,降低ADPG供应水平,影响淀粉的积累,以及旗叶AGPase活性对净光合速率的不良影响,是籽粒不饱满的重要原因之一。 相似文献
7.
Reduced Sink Activity in Growing Shoot Tissues of Maize under Salt Stress of the First Phase may be Compensated by Increased PEP‐Carboxylase Activity 
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下载免费PDF全文 B. W. Hütsch T. Osthushenrich F. Faust A. Kumar S. Schubert 《Journal of Agronomy and Crop Science》2016,202(5):384-393
The effects of salt stress (100 mm NaCl for 6 days) on growing tissues (shoot apex, growing leaf segments, root tips) of young maize plants (Zea mays L. cv. Pioneer 3906) were investigated in comparison to an unsalinized control, focusing on assimilate supply from source leaves and the activity of sucrolytic enzymes in the sink tissues. The objectives were to test whether (i) phloem unloading in growing tissues is mainly symplastic, (ii) salinity reduces sink activity, determined either as sucrose synthase activity (indicator for the symplastic pathway) or as acid invertase activity (indicator for the apoplastic pathway), and (iii) PEP‐carboxylase activity is increased under salinity to compensate for reduced sink activity. For growing tissues of young maize shoots, it can be assumed that phloem transport of sucrose is mainly driven by symplastic unloading into the sink cells. In maize root tips, both, apoplastic and symplastic pathways, contributed to carbohydrate supply to the sink cells. The activity of acid invertase in growing shoot tissues was very low, and the alkaline invertase contributed less than 10 % to the cytoplasmic sucrolytic activity. Salt stress of the first phase (mainly osmotic stress) caused a significant inhibition of acid invertase activity in the growing leaf segments and in the root tips, which was also true for alkaline invertase activity in the root tips as well as for sucrose synthase activity in root tips and shoot apex. The decrease of sucrose synthase activity in shoot apex might be particularly detrimental for the plant growth, as this tissue with a high cell division rate relied entirely on cytoplasmic enzyme activities. Under salt stress, PEP carboxylase activity was significantly increased in growing leaves and the shoot apex of maize, whereas no significant effect was observed in the root apex. In conclusion, PEP carboxylase can have an anaplerotic function supporting the demand for metabolites in growing shoot tissues of young maize plants under salt stress. In root tips, an additional supply of organic acids to the tricarboxylic acid cycle is probably not needed, as sucrolytic sink activity, which was high even under saline conditions, can meet the demand of the sink cells. 相似文献
8.
F. Akinerdem 《Plant Breeding》1991,107(4):333-337
To improve estimates of the true ploidy level of pure diploid triploid, and tetraploid sugar beet (Beta vulgaris L.) plants, and of populations of mixed ploidy, the effect of leaf age/size was evaluated on ploidy determination by flow cytometry. There were significant differences between old and young leaves, with young leaves giving the best estimate of the true ploidy level of the plants. The old leaves seemed to express a high degree of endopolyploidy. 相似文献
9.
植物原生质体是细胞培养和体细胞融合等细胞水平研究及植物遗传育种的重要材料。本研究用福鼎大白茶茶树的幼嫩叶片及胚根, 分析了原生质体分离过程中的材料、酶解液组成及酶解时间、纯化方法等影响因子, 建立了最佳原生质体分离体系, 为茶树体细胞杂交等细胞水平的研究提供了高效获取大量高活力原生质体的方法。结果表明, 23°C恒温黑暗或遮光培养的茶树实生苗的5周叶龄以内的幼嫩叶片是茶树原生质体分离的最佳材料, 其次是茶树种子萌发后的幼嫩胚根; 而以茶园健康生长的5周叶龄以内的幼嫩叶片为材料时, 只能获得混有大量细胞碎片的少量具有活力的原生质体。以茶树幼嫩叶片为分离材料的酶解液组成为1.5%纤维素酶+0.1%离析酶+0.5%果胶酶+0.4 mol L-1甘露醇+20 mmol L-1 MES; 以茶树幼嫩胚根为分离材料的酶解液组成为1.5%纤维素酶+0.3%离析酶+0.5%果胶酶+0.4 mol L-1甘露醇+20 mmol L-1 MES。分离茶树幼嫩叶和幼嫩胚根原生质体时, 宜采用低速(分别为55 r min-1和50 r min-1)恒温(23°C)摇床振荡酶解培养, 时间分别为7 h和8 h; 最适宜采用15×g的转速, 离心4 min可纯化获得高产量和活力的原生质体。用40% PEG-6000诱导20 min后可使茶树原生质体融合, 融合率达10%。 相似文献
10.
绿盲蝽危害后转Bt基因棉花嫩叶的几个生理指标变化特征分析 总被引：1，自引：0，他引：1
以转Bt基因棉品系苏抗310和其轮回亲本泗棉3号为材料,研究绿盲蝽危害后转Bt基因棉花顶部嫩叶的几个相关生理指标的变化特征。结果表明：绿盲蝽危害后,棉花顶叶的叶绿素、可溶性蛋白和游离氨基酸含量显著降低,说明绿盲蝽危害后,棉花顶部嫩叶氮代谢受到一定破坏,引起叶绿素含量的下降,这对叶片成熟后光合作用是不利的。棉花顶部嫩叶受危害后,缩合单宁含量提高和苯丙氨酸解氨酶（PLA）活性增强,表明棉花植株抵御盲蝽危害能力提高,但转Bt基因棉品系顶部嫩叶缩合单宁含量和PLA活性低于非转Bt基因棉品种;即使是绿盲蝽危害后的顶部嫩叶也均未达到非转Bt基因棉品种正常水平,这可能是导致转Bt基因棉盲蝽危害加重的原因之一。棉花顶部嫩叶受害后,非转Bt基因棉泗棉3号可溶性糖含量降低,而转Bt基因棉品系苏抗310升高;非转Bt基因棉品种受绿盲蝽危害后顶部嫩叶可溶性糖含量降低,不利于绿盲蝽的发生,而转Bt基因棉品系受危害后顶部嫩叶可溶性糖含量上升,不利于对绿盲蝽的危害控制,这可能是转Bt基因棉绿盲蝽危害重于非转Bt基因棉的又一原因。 相似文献
11.
12.
巴西橡胶树幼叶和成熟叶比较蛋白质组学初步研究 总被引：1，自引：1，他引：0
为研究不同发育时期橡胶树叶片的功能代谢及揭示天然橡胶胶乳的合成调控机制,本研究以巴西橡胶树古铜期幼嫩叶片（幼叶）和稳定期完全成熟叶片（成熟叶）为实验材料,提取蛋白并进行双向电泳分离,结果发现幼叶与成熟叶相比,蛋白表达图谱差异显著,鉴定出的已知蛋白中多数参与了碳代谢及蛋白的翻译后修饰功能。本研究建立了成熟的巴西橡胶树叶片比较蛋白质组学研究的技术体系,获得了高分辨率的叶片蛋白双向电泳参考图谱,鉴定出来的腈裂解酶A链,核酮糖1,5-二磷酸羧化酶和肌动蛋白等在幼叶和成熟叶片中的表达量不同,这些结果为进一步揭示天然橡胶合成调控机制提供了一定的技术支撑与实验数据,对天然橡胶合成机制的研究以及其它热带植物叶片的蛋白质组学研究具有一定的参考意义。 相似文献
13.
棉花主茎叶与根系硝酸还原酶活性分布对播期和密度的响应 总被引：1，自引：1，他引：0
【目的】本研究旨在探讨大田轻简化栽培条件下棉花氮代谢随播期和密度的变化规律。【方法】选用华棉3109(G.hirsutum L.)于2014年在华中农业大学试验农场,采用裂区设计:播期为主区(S1,5月30日;S2,6月14日),密度为副区(D1,7.5株·m-2;D2,9.0株·m-2;D3,10.5株·m-2),研究了硝酸还原酶(Nitrate reductase,NR)活性在主茎叶位和根系的分布特点。【结果】1)不同播期和密度对叶片和根系NR活性平均值有显著影响。推迟播期对现蕾期棉花叶片与根系平均NR活性无显著影响,增加密度可降低叶片平均NR活性,但对根系平均NR活性无显著影响;推迟播期,显著降低初花期和盛花期棉花叶片NR活性平均值,但晚播对根系NR活性平均值的影响由侧根NR决定,增加密度,叶片和根系平均NR活性呈先升高后降低变化趋势,表明见花施肥后,晚播抑制了棉花地上部叶片氮代谢强度,而增强了地下部根系氮代谢强度;适度增加密度可显著增强棉花地上部叶片和地下部根系氮代谢强度。2)现蕾期叶片NR活性平均值初花期盛花期,根系NR活性平均值大体呈先升高后降低变化趋势。3)主茎叶位NR活性在3个时期均由上而下显著降低,以第1叶至第3叶波动较大,第4叶以下叶片间无显著差异,表明叶片NR活性与叶龄有关,幼叶氮代谢强度高于成熟叶片,成熟叶片之间氮代谢强度保持相对稳定。【结论】长江流域棉区(主要指湖北植棉区)棉花播种不应晚于6月14日,种植密度以9.0株·m-2最佳。 相似文献
14.
水分胁迫下乙烯利浸种对甘蔗叶片蛋白质和核酸的影响 总被引：1，自引：0，他引：1
采用3不同浓度乙烯利溶液（0mg/L、100mg/L、200mg/L）分别对ROC22、GT17和ROC10在下种前进行10min浸种处理后进行桶栽砂培试验,并在甘蔗苗期（4~5叶）进行自然土壤干旱胁迫,研究水分胁迫下乙烯利浸种对参试品种叶片蛋白质和核酸等的影响。结果表明：在水分胁迫下及复水后,乙烯利浸种处理有较高的叶片蛋白质含量和总核酸含量,同时有较低的蛋白酶活性;水分胁迫下乙烯利处理可以显著提高ROC22和GT17叶片RNA/DNA值,复水后,乙烯利处理对各品种叶片的RNA/DNA值都有促进效应。从而增加甘蔗的分蘖。 相似文献
15.
Rapeseed (Brassica napus L. var. oleifera) is known to display adaptive responses under drought stress, especially in leaves. The aim was to study the influence of water deficit on endoproteolytic activities and water status of leaves developed before (L3 leaf) or after the onset of water stress (L2 and L3 leaves). Although the impact of senescence on proteolytic activities is well known, little information is available on the effect of water deficit on such activities. Seedlings of rapeseed were submitted to controlled progressive drought. Soil water potential (T) and soil dry weight humidity (H) were measured daily in the dark. Endoproteolytic activities were assayed both on control and water-stressed plants using azocasein as substrate after partial purification of the extracts, Two zones of maximal activity were detected, the first between pH 4.5 and 6.0 and the second at pH 8.0 as a sharp peak, in control as well as in drought stressed-plants. While LI leaf was very sensitive to water stress and wilted when ψ reached −2.8 to −3.2 MPa, L2 leaf began to display signs of senescence for this value whereas L3 leaf which showed the lowest endoproteolytic activities, remained turgid, hardened and developed a typical bluish coloration. The relation between the acquired resistance of young leaves, the low endo-proteolytic activity and the induction of a 22 kDa protein under progressive drought is discussed. 相似文献
16.
Diploidization in Haploid Tissue Cultures of Sorghum 总被引：1，自引：0，他引：1
Conditions for the effective experimental regulation of ploidy level in regenerants from callus cultures derived from young, undifferentiated leaves and panicles of haploid sorghum were established. Diploidization depended on the ontogenetic age of the explant and the 2,4-D concentration in the medium. With a low 2,4-D concentration (0.5 mg/1) and segments of young panicles (< 35 mm long) the cultures produced only haploid regenerants. Diploid plants were formed from cultures derived from more mature panicles ( 35 mm long) and young leaves (15–65 mm long). Under a high 2,4-D concentration (2.5 mg/1) diploid plants were regenerated from cultures derived from young panicles (less than 35 mm) except the most young ones (5–15 mm). The majority of the diploid regenerants contained mutations, mainly affecting male fertility and plant height. 相似文献
17.
对柠檬春花期新梢进行抹除(抹梢);修剪柠檬花期过密花枝,同时抹除抽发的新梢(抹梢+修剪),统计分析有叶枝梢花量、无叶枝梢花量、有叶果量、无叶果量、枝梢叶片数量、单株产量。旨在研究抹梢和修剪处理对柠檬春花秋熟果花果调控的影响,为提高柠檬产量及柠檬的花期调控理论提供科学依据。结果表明:不同处理间柠檬带叶枝梢花量和无叶枝梢花量的差异均不显著;不同处理对柠檬有叶果量和无叶果量影响较大。生理落果完成后,不同处理间有叶果量和无叶果量差异显著,均为修剪+抹梢处理最多,抹梢处理次之,对照最少;不同处理对枝梢叶片数量的影响较小,差异不显著;不同处理间柠檬单株产量差异均达到显著或极显著水平。同一年度不同处理单株产量大小依次为:修剪+抹梢抹梢对照,2010、2011年抹梢处理分别比对照增加45.0%、33.8%,修剪+抹梢分别比对照增加86.2%、71.9%。综合考虑,柠檬春花果修剪+抹梢调控效果最好。 相似文献
18.
Ammonia Metabolism in the Leaves and Ears of Wheat (Triticum aestivum L.) During Growth and Development 总被引：1，自引：0，他引：1
The pattern of free NH4 + accumulation and its metabolism was studied during the growth and development of field-grown wheat cv. HD 2204 at two applied N levels viz. 30 and 120 kg ha−1 . The study was confined to the 3rd, 5th and flag leaf blades and the developing ears, borne on the main shoot, during their ontogeny. The NH4 + levels were considerably lower in young leaves and increased sharply as the leaves senesced when the activity of glutamine synthetase (GS) declined. In contrast to GS, glutamate dehydrogenase (GDH) remained active even during senescence. Concentrations of protein, free amino acid and total reduced N declined with age in the leaves. An assessment of free NH4 + pool, free amino acid content and the activity of GS and GDH in the floral parts revealed that glumes, awns and grains also were active sites of NH4 + turnover. Higher applied N level not only increased leaf and grain N concentration but also led to higher free NH4 + levels in leaves and in developing ears. Presence of NH4 + in the entrapped transpirate revealed that NH4 + is released from both leaves and ears during senescence. 相似文献
19.
β-淀粉酶(BAM)是植物中参与淀粉水解的关键酶类,在应对非生物胁迫中发挥重要作用。从前期茶树冷驯化转录组分析中分离到1个参与淀粉代谢的差异表达基因,cDNA全长克隆及序列分析鉴定该基因为拟南芥BAM3同源基因,命名为CsBAM3。该基因编码548个氨基酸残基,与拟南芥的BAM1和BAM3一起归为第Ⅱ亚家族,推测为叶绿体定位、具有淀粉水解活性的β-淀粉酶编码基因。启动子克隆及序列分析显示该基因可能受生理节律、光、低温及多种激素等信号共同调控。CsBAM3在叶片中表达量最高,茎和花中表达量较低,根中基本不表达。CsBAM3在冷驯化初期被显著上调且一直保持相对较高的水平。成熟叶片及嫩芽(一芽二叶)中的CsBAM3均可以被4℃及0℃低温显著上调,且嫩芽中基因的表达量上调幅度明显高于成熟叶。模拟倒春寒低温条件下,检测不同萌发阶段新梢中CsBAM3的表达情况表明,CsBAM3在鲜叶初展的嫩芽中即可快速受低温诱导。以上结果表明,CsBAM3是茶树中调控淀粉水解的一个重要β淀粉酶编码基因,在茶树成熟叶和嫩芽受到不同低温胁迫时其表达可被快速诱导。 相似文献
20.
减数分裂期高温胁迫对耐热性不同水稻品种产量的影响及其生理原因 总被引：25，自引：0，他引：25
以两个耐热性不同的籼稻品种为材料,在减数分裂期进行高温(白天温度>35℃)处理,以同期自然温度(白天温度<33℃)为对照,研究减数分裂期高温对产量的影响及其生理机制。结果表明,高温处理与对照相比,显著降低了热敏感品种双桂1号的花药开裂率及花粉育性,对耐热品种黄华占影响较小;明显降低了每穗颖花数、结实率和粒重,从而使产量显著下降,其中耐热品种下降幅度小于热敏感品种;热敏感品种粒宽显著缩短,长宽比显著增大,而对耐热型品种影响不大;明显降低了水稻的根系活力和幼穗的核糖核酸(RNA)含量,显著增加了叶片丙二醛(MDA)含量和幼穗的乙烯释放速率,热敏感品种变化幅度大于耐热品种;显著增加了耐热品种叶片的抗氧化酶活性,对热敏感品种无显著影响。总之,根系活力和抗氧化保护系统能力强、RNA含量高、MDA含量低及乙烯合成少是耐热性品种在高温胁迫下保持较高产量的重要生理原因。 相似文献