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941.
Li Shuye Ma Huijuan Zhang Siping Liu Shaodong Shen Qian Chen Jing Ge Changwei Pang Chaoyou Zhao Xinhua 《棉花学报》2018,30(3):252-260
[Objective] The objective of this study was to investigate the effects of exogenous 24-epibrassinolide (EBR) on the photosynthetic physiology of cotton seedlings under low temperature and to provide basis for improving the cold tolerance of cotton by using EBR as growth regulator. [Method] Taking CCRI 60, Lumianyan 28 and Simian 3 as materials, a field experiment was carried out in Institute of Cotton Research of CAAS(Anyang county, Henan province). Before the first low temperature treatment, the cotton seedlings were sprayed with distilled water (Control) and different concentrations of EBR (0.1 mg·L-1 and 0.2 mg·L-1), respectively. After 3 days, the relative electrical conductivity, chlorophyll content, rapid chlorophyll fluorescence induction kinetic curve (OJIP) and fluorescence parameters were measured. [Result] Under low temperature, the relative conductivity of CCRI 60, Lumianyan 28 and Simian 3 spraying with EBR decreased by 17.7%~32.8% compared with control, and there was no significant difference between CCRI 60 and Lumianyan 28 in different concentrations of EBR treatments, butthe relative conductivity of Simian 3 treating with 0.2 mg·L-1 EBR was significantly lower than those treatments with 0.1 mg·L-1 EBR . The chl a and chl b contents increased by 9.7%~32.6% and 15.0%~18.9%, respectively. The maximum photochemical efficiency of photosystemⅡ (Fv/FM) and photosynthetic performance index on absorption basis(PIABS) increased significantly. PIABS of CCRI 60 increase the maximum by 75.6% using 0.1 mg·L-1 EBR. Lumianyan 28 and Simian 3 increased the maximum by 101.1% and 265.6% using 0.2 mg·L-1 EBR, respectively; Absorbed photon flux per cross section (ABS/CSm), electron transport flux (further than QA) per active reactive center (ETo/RC) and probability for electron transport (φEo) are significantly increased. [Conclusion] Exogenous EBR can enhance the ability of low temperature tolerance of cotton seedlings and alleviate the inhibition of photosynthesis in cotton at low temperature. The study showed that 0.1 mg·L-1 EBR performs well in CCRI 60 and 0.2 mg·L-1 in Lumianyan 28 and Simian 3. 相似文献
942.
Luo Yao Ding Jiayu Shen Yougang Tan Wenfeng Liu Fan Qiu Guohong 《Journal of Soils and Sediments》2018,18(2):564-575
Journal of Soils and Sediments - The oxidation of ferrous sulfide (FeS) causes soil acidification and the release of toxic heavy metal ions. Manganese oxides usually participate in the oxidation of... 相似文献
943.
944.
该文介绍了环巢湖农家乐的发展现状,分析了环巢湖农家乐旅游发展中存在的问题,并提出了进一步发展环巢湖农家乐的对策建议。 相似文献
945.
本研究探讨海滨雀稗EST序列中SSR位点的分布特征,开发EST-SSR引物分析其在草坪草种质资源遗传多样性研究中的应用。利用SSRIT软件对81220条海滨雀稗EST序列进行SSR位点搜索,分析EST-SSR的分布和特点,并利用Primer 3.0软件设计50对引物,选择10份草坪草对引物进行有效性和多态性检测。结果表明,从13705条海滨雀稗EST序列中检测到了22721个SSR位点,出现频率为16.87%。三核苷和单核苷酸重复为主要类型,所占比例分别为31.71%和29.28%。在检测到的163种基元中,出现最多的重复基元是A/T,其次是CCG/CGG和AGC/CTG。选择合成了50对EST-SSR引物,以海滨雀稗‘Adalady’基因组DNA为模板进行PCR扩增,其中37对引物能扩增出条带。利用这些引物对10份草坪草品种进行多态性检测,其中12对引物的扩增结果具有多态性。利用开发的EST-SSR标记对10份草坪草进行聚类分析,可将其分为4类。利用海滨雀稗EST序列开发SSR标记是可行的,开发的EST-SSR标记能有效用于草坪草遗传多样性研究。 相似文献
946.
947.
Korean pine(Pinus koraiensis Sieb. et Zucc.) is an ecologically and economically important tree species in East Asia. Molecular studies of seed development of this species are limited due to the lack of effective RNA extraction protocols. This study aimed to obtain an effective method to extract high-quality RNA from Korean pine seeds. The TRIzol kit and CTAB methods were used to extract the total RNA from Korean pine seeds at different developmental stages. The bands of RNA extracted by CTAB were not clear, whereas the bands of RNA extracted by the TRIzol kit were brighter and clearer, indicating higher quality and integrity of the RNA products extracted by the TRIzol kit. The 28 S r RNA band was approximately1.5- to 2-fold brighter than the 18 S r RNA band on the agarose gel electrophoresis. The absorbance value A260/280 was 1.8–2.0, and the absorbance value A 260/230 was [1.9. The Bioanalyzer RNA integrity results showed that the RNA integrity number of the RNA extracted using the TRIzol kit was acceptable for high-throughputsequencing. Therefore, the total RNA extracted using the TRIzol kit method can be used for high-throughput sequencing and other molecular biology experiments. 相似文献
948.
949.
为了揭示安吉县竹产业发展趋势,进一步分析其原因,本文选取了安吉县2010-2015年春、秋季共10次招聘会的招聘数据信息,对安吉县竹产业发展趋势进行了分析。结果显示:近年来安吉县竹产业招聘企业和岗位数量及其比例均不断下降,反映了安吉竹产业正处于逐步下行的趋势,其在国民经济中的相对地位也在不断下降。分析其原因主要是:竹产品市场份额减少,产品相对过剩;中西部竹产业发展带来冲击;在竹资源培育方面投入劳动力不足,在加工方面机械化程度低;竹产业自身转型急需升级等,并就此提出了对策建议。 相似文献
950.
Guo-Ming Shen 《Communications in Soil Science and Plant Analysis》2016,47(15):1721-1730
To evaluate the effect of nitrogen, light, and water interaction on the biomass of cabbage the experiment was performed at three light intensities, three water stresses, and four nitrogen levels for four replicates using hydroponic technique in green house. The results showed that the biomass of the edible parts of cabbage at H1L3 was significantly higher than in weak light intensity and water stress treatments under the same nitrogen supply. An optimal yield was reached at 60% of the traditional nitrogen application in the presence of adequate high light intensity and normal water content. Decreased nitrate reductase and low capacity of nitrogen assimilation were observed when the nitrate–nitrogen (NO3-N) levels were increased from N2 to N4 with normal water content. Under severe water stress (H3), the plants have a high content of soluble sugars and a low content of amino acids in low NO3? levels (N1 to N3). Modulating the relationship between water stresses, light intensity, and nitrogen supply levels could increase the biomass and may promote the quality of a certain plant. 相似文献