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排序方式: 共有321条查询结果,搜索用时 359 毫秒
21.
为了初步探索光核桃(Amygdalus mira)亚硫酸盐氧化酶(Sulfite oxidase,SO)的蛋白结构与功能,以1 a生光核桃叶片cDNA为模板,采用分子克隆技术获得光核桃AmSO基因全长为1 182 bp的开放阅读框(ORF),共编码393个氨基酸,相对分子质量是43.45 ku。生物信息学分析结果显示,AmSO蛋白是一种能在细胞核内发挥生物学作用的稳定碱性亲水蛋白,二级结构由无规则卷曲、α-螺旋和延伸链构成。蛋白结构域的预测及氨基酸序列同源性比对发现,编码氨基酸序列的N端具有氧化钼结构域,常存在于氧化还原酶中,可以与钼辅因子结合;在C端具有钼钴(Mo-co)二聚体结构域,该结构域参与二聚体的结合,并且能够参与硫、氮和碳循环中的氧化还原反应,二者在进化过程中高度保守。系统进化树分析表明AmSO与碧桃PpSO亲缘性最近,进化相对保守。对光核桃AmSO蛋白进行生物信息学预测,有助于进一步系统研究光核桃 AmSO基因在生物学上的功能,为进一步了解其对非生物胁迫的响应机制奠定基础。 相似文献
22.
M. R. Arab 《The Journal of Horticultural Science and Biotechnology》2016,91(3):236-242
Adventitious shoot regeneration from mature cotyledons of GF677 rootstock (Prunus persica × Prunus amygdalus) was achieved in vitro. Thidiazuron (N-phenyl-N-1,2,3-thidiazol-5-yl-urea; TDZ) at 32 µM gave the highest percentage of cotyledons forming adventitious shoots (68.8%) and the highest number of shoots per cotyledon (4.8) on Quoirin and Lepoivre (QL) medium. On QL medium containing 32 µM TDZ, exposure of the proximal segments of cotyledons to darkness at the start of culture increased the percentage of cotyledons forming adventitious shoots (62.5%) when compared with those kept under light conditions (15%). A combination of 0.72 µM gibberellic acid and dark treatment resulted in at least 2.7-fold more elongated shoots than non-treated shoots. The highest rooting percentage (100%) occurred on 0.5× Murashige and Skoog medium supplemented with Gamborg (B5) vitamins and 2 mg l?1 indole-3-butyric acid. Rooted plantlets were acclimatised under greenhouse conditions with a 70% survival rate. 相似文献
23.
Effects of Nitric Oxide and Exogenous Ethylene Treatments on Ethylene Biosynthesis in Feicheng Peach 总被引:1,自引:0,他引:1
LIU Meng-chen SONG Wei-hong ZHU Shu-hua ZHOU Jie 《中国农业科学(英文版)》2007,6(3):290-295
The effects of nitric oxide (NO) and exogenous ethylene on ethylene biosynthesis in harvested Feicheng peaches were studied. The antagonistic actions between NO and exogenous ethylene was also investigated. The Feicheng peaches were fumigated with 10μL L^-1 NO, 1 000 μL L^-1 ethylene, or 10 μL L^-1 NO plus 1 000 μL L^-1 ethylene for 3 h. The results suggested that application of exogenous ethylene promoted the biosynthesis of endogenous ethylene in peach fruit. The treatment with NO remarkably inhibited the biosynthesis of ethylene by significantly reducing the activities of ACC synthase (ACS) and ACC oxidase (ACO). Ethylene biosynthesis in the fruits treated with both NO and exogenous ethylene was lower than that in fruits treated with exogenous ethylene alone but higher than that in fruits treated with NO alone, suggesting that there were antagonistic actions between NO and exogenous ethylene. NO could inhibit the biosynthesis of ethylene and the catalysis of exogenous ethylene during ethylene biosynthesis in peach fruits. 相似文献
24.
不同光强处理对设施桃树光合及荧光特性的影响 总被引:28,自引:1,他引:28
以二年生“春捷”毛桃为试材,研究了日光温室内遮荫处理桃树在不同光照强度条件下光合特性以及荧光特性的变化。结果表明:随着光照强度的降低,桃树叶片的光补偿点、光饱和点、CO2饱和点(CSP)、CO2补偿点(CCP)、Rubisco活性、表观光合量子效率(AQY)、光呼吸速率、乙醇酸氧化酶(GOX)活性和羧化效率(CE)均呈下降趋势;光合色素含量在不同光强条件下变化较大,两个弱光处理叶绿素a(Chl.a)、叶绿素b(Chl.b)、 类胡萝卜素(carotenoids)的含量均比对照升高。不同光强条件对桃树叶片的荧光参数φPSⅡ、Fo和Fv/Fm的日变化影响显著,弱光照处理的φPSⅡ、Fv/Fm的日变化比较平稳而且维持在一个较高的水平,而对照的上述两个参数的日变化波动较大;三个不同光强处理的Fo的日变化均是在10:00开始上升,在13:00达到最高点而后下降,变化趋势基本一致。 相似文献
25.
26.
利用RAPD技术对碧桃种质资源的分析 总被引:1,自引:0,他引:1
程中平 《西南大学学报(自然科学版)》2003,25(1):4-6
利用RAPD技术,采用从200个随机引物中筛选的22个随机引物对8个碧桃类型的基因组DNA进行扩增,通过扩增的180个位点的谱带的聚类,分析供试碧桃的系统发育,并运用特殊谱带,建立了碧桃的分子检索表,并提出了重点保存的碧桃种质。 相似文献
27.
树形对油桃幼树光截获能力和结果的影响 总被引:8,自引:1,他引:8
【目的】研究设施栽培中树形对幼树光截获能力和生长结果的影响。【方法】以一、二年生油桃沪油004为试材,设计4种树形、在生长季节用不同浓度梯度的多效唑树冠叶面喷施处理的方法。【结果】(1)树形对冠层消光系数(K)的影响表现为主干形>Y形>开心形>十字形,十字形和开心形叶面积指数(LAI)之间无明显差异,但都稍高于主干形而极显著大于Y形;冠层光直接辐射透过系数(Tr)和光散射辐射透过系数(TDP)的大小表现为Y形>开心形>十字形>主干形。(2)多效唑处理后,幼树单株平均果实数和平均单果重均表现为主干形多于Y形,而每667m2平均产量则以主干形较高。【结论】设施栽培中采用主干形,树冠形成早期光截获能力较高。多效唑对不同树形的生长结果均产生一定的影响。 相似文献
28.
The prevailing environmental conditions, temperature in particular, drive seasonal changes both in leaf development and stomatal characteristics. In order to ascertain the effect of increases in climatic water deficit on some leaf and stomatal parameters under field conditions, a study was carried out on two sets of leaves (spring and summer) on a large sample of Amygdalus communis L. cultivars in comparison with several Amygdalus webbii Spach seedlings, a species more adapted to arid environments and probable ancestor of cultivated almonds. Observations were performed between spring and summer of a particularly hot season. The results showed a significant and general reduction of both leaf area and stomatal frequency and an increase in stomatal size. Nevertheless, there were evident differences between cultivated and wild almonds. A stronger reduction of leaf area was observed in A. webbii (−31%) with respect to A. communis (−14%); on the contrary, the latter reduced stomatal frequency more than the former (−25% and −19%, respectively). The examined cultivated almonds, in response to the increase in climatic water deficit, tended to arrange their stomatal structures like those of wild almonds. Finally, increasing the climatic water deficit, the slope of the linear regressions between stomatal frequency and size did not change in either species, leading to a better understanding of the mechanisms of almond acclimation to environmental stresses. 相似文献
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