吖啶酮衍生物作为增强型荧光信号探针用于8-羟基喹啉铜的检测

[目的]建立一种检测8-羟基喹啉铜的方法.[方法]采用自制合成的吖啶酮衍生物10-甲基-3-硝基-吖啶酮(MAT)作为增强型荧光信号探针,建立8-羟基喹啉铜的测定方法.[结果]在最佳条件下荧光增强值与8-羟基喹啉铜的浓度在5×10-9 ～5 ×10-5 mol/L范围内成良好的线性关系,检测限为6×10-10 mol/L.[结论]该方法灵敏度高、检测范围宽,结果令人满意,可用于实际样品中8-羟基喹啉铜含量的直接测定.     

松杨栅锈菌无性发育阶段组织学染色方法1）

观察并分析了荧光增白剂和偶联Alexa 488荧光素的小麦凝集素2种荧光染色方法对松杨栅锈菌（ Melampsora larici-populina）无性发育不同阶段的染色效果。结果表明：偶联Alexa 488荧光素的小麦凝集素染色处理后能够较清楚地观察到锈菌的夏孢子、萌发的芽管、附着胞、气孔下囊、侵染菌丝、吸器母细胞及吸器等不同发育阶段的结构,荧光增白剂处理后不易观察到锈菌的侵染菌丝、吸器母细胞及吸器等结构。因此,偶联Alexa 488荧光素的小麦凝集素荧光染色方法可以作为研究松杨栅锈菌与寄主杨树互作的一种组织病理学方法。     

Fluorescence and NIR spectroscopic study on the water interaction in polycarbonate film

Water interactions in polycarbonate films have been studied using fluorescence and NIR Fourier transform spectroscopy. During water sorption process, the fluorescence emission spectra showed sensitive changes with the peak at 332 nm red shifted by 18 nm with water sorption. This red-shifted peak could be due to phenyl-2-phenoxybezoate, which is one of two major thermal degradation products in polycarbonate. In the spectra of phenyl-2-phenoxybenzoate in dimethyl formamide solution, a progressive red shift was also observed with the water addition. By using the NIR spectra, hydrogen-bonding interactions of the sorbed water with polycarbonate were investigated. It was found that water can be analyzed as free water S₀ or single hydrogen bonded water, S₁ while double hydrogen bonded water was negligible. During water immersion, most water species which are present as S₀ species decrease slightly, with a small increase in S₁ species. During desorption, S₀ species decrease sharply, while S1 species is reduced gradually. Two examples of S₁ structure in water-sorbed polycarbonate are proposed.     

翡翠贻贝肾CYP4基因表达受多氯联苯影响的研究

[目的]了解多氯联苯(PCB)对翡翠贻贝肾中细胞色素P450第4亚族(CYP4)基因表达的影响。[方法]从野生翡翠贻贝cDNA中扩增得到了翡翠贻贝CYP4基因和β-actin基因的部分cDNA序列,并根据所得序列设计定量PCR引物,以β-actin为内参基因,以SYBRGreenI为荧光染料,利用荧光定量PCR对经PCB暴露处理后的翡翠贻贝肾中CYP4基因表达水平进行定量测定。[结果]PCB暴露处理对翡翠贻贝肾中CYP4基因的表达有明显的诱导作用,并且这种诱导作用对CYP4表达水平的影响与PCB暴露处理的时间以及浓度有相关性。[结论]该研究为CYP4基因作为生物大分子标记物在环境监测领域的应用提供了分子生物学水平的支持,同时为海水双壳类动物体内CYP4基因功能的研究提供了有益线索。     

Analysis of introgression of the Tulipa fosteriana genome into Tulipa gesneriana using GISH and FISH

Southern hybridization and genomic in situ hybridization (GISH) have demonstrated that ‘Purissima’ (2n = 2x = 24) is an interspecific hybrid comprised of one genome of Tulipa (T.) gesneriana and one genome of T. fosteriana. Backcrossing T. gesneriana with ‘Purissima’ was partially successful. Simultaneous GISH and fluorescence in situ hybridization (FISH) distinguished chromosomes from both parent genomes, as well as recombinant chromosomes, in interspecific hybrids and their progeny. Chromosome recombination was observed in all cultivars except ‘Purissima’ and ‘Kouki’ (2n = 3x = 36). ‘Kouki’ (2n = 3x = 36) had two genomes of the T. gesneriana and a single genome of the T. fosteriana. The number of nonrecombinant T. fosteriana chromosomes in ‘Judith Leyster’ (2n = 4x = 48) and ‘Purissima’ progeny varied from two in ‘Hatsuzakura’ to six in ‘Kikomachi’ and ‘Momotaro’. The number and type of recombinant chromosomes also differed among cultivars. The total number of translocations ranged from one in ‘Kikomachi’ to six in ‘Hatsuzakura’. Each was a combination of a single T. fosteriana fragment and a single T. gesneriana fragment, indicating that they resulted from a single crossover event. Sequential GISH and FISH analysis with rDNA probes yielded chromosome-specific markers that were used to identify most of the chromosomes in ‘Purissima’ progeny. This is the first report of introgression of T. fosteriana chromatin into the T. gesneriana genome.     

Map- vs. homology-based cloning for the recessive gene ol-2 conferring resistance to tomato powdery mildew

The recessive gene ol-2 confers papilla-associated and race-non-specific resistance to tomato powdery mildew caused by Oidium neolycopersici. In order to facilitate marker assisted selection (MAS) in practical breeding programmes, we identified two simple sequence repeat (SSR) markers and one cleaved amplified polymorphic sequence (CAPS) marker which are linked to the resistance locus and co-dominantly inherited. Aiming to provide a base for ol-2 positional cloning, we used a large segregating F₂ population to merge these markers with all the ol-2 linked amplified fragment length polymorphism (AFLP^®) markers previously identified in an integrated genetic map. By screening a tomato bacterial artificial chromosome (BAC) library, we detected two BAC clones containing two expressed sequence tags (ESTs) homologous to the gene mlo, responsible for powdery mildew resistance in barley, as well as an ol-2-linked marker. Chromosomal mapping by Fluorescence in situ Hybridization (FISH) revealed major signals of the two BAC DNAs in the pericentromeric heterochromatin of the short arm of chromosome 4, in the same region where the ol-2 gene was previously mapped. The genetic and cytogenetic co-localisation between ol-2 and tomato mlo-homologue(s), in addition to the similarity of ol-2 and mlo resistances for both genetic and phytopathological characteristics, suggests that ol-2 is likely a mlo-homologue. Thus, a homology-based cloning approach could be more suitable than positional cloning for ol-2 isolation.     

Preliminary Study on the Photosynthetic Characteristics of Super Hybrid Rice P88S/0389

[Objective] The aim of this study is to understand the high yield often photosynthetic mechanism of super hybrid rice P88S/0389.[Method] Chlorophyll and carotenoid contents were measured via the method of Wellburn and Lichtenthaler,and the photosynthetic rate and chlorophyll fluorescence parameters were measured using portable photosynthesis system.Through comparison of above measured indices between P88S/0389 and its parents,the photosynthetic characteristics were obtained.[Result] The pigment content of P88S/0389 lied between their parents,and detailedly was closer to its female parent at earlier growth stage and to its male parent at latter stage,respectively.The Pn,Fv/Fo,Fv/Fm and qP of the flag leaf of P88S/0389 were all higher than those of its parents,while the degradation rates of these parameters were slower than those of its parents.The qN of flag leaf was lower than those of its parents,and the increasing rate of qN of P88S/0389 was also slower than those of its parents,indicating the great heterosis of P88S/0389 to its parents in photosynthetic capacity.The data show that P88S/0389 is endowed with stronger capacities in light energy absorption,transformation and carbon fixation compared to its parents.[Conclusion] The light energy absorbed by hybrid mainly contributes to photochemical reaction,and little for heat dissipation.For ensuring high yield,the rice cultivars selected for production should synchronously possess higher photosynthetic rate and longer high value duration.     

Detection of citrus canker in citrus plants using laser induced fluorescence spectroscopy

Citrus canker is a serious disease caused by Xanthomonas citri subsp. citri bacteria, which infects citrus plants (Citrus spp.) leading to a large economic loss in citrus production worldwide. In Brazil citrus canker control is done by an official eradication campaign, therefore early detection of such disease is important to prevent greater economic losses. However, detection is difficult and so far it has been done by visual inspection of each tree. Suspicious leaves from citrus plants in the field are sent to the laboratory to confirm the infection by laboratory analysis, which is a time consuming. Our goal was to develop a new optical technique to detect and diagnose citrus canker in citrus plants with a portable field spectrometer unit. In this paper, we review two experiments on laser induced fluorescence spectroscopy (LIF) applied to detect citrus canker. We also present new data to show that the length of time a leaf has been detached is an important variable in our studies. Our results show that LIF has the potential to be applied to citrus plants.     

茶多酚绿色荧光特性研究

以茶多酚为材料,研究了茶多酚浓度、溶液pH、溶剂、金属离子（Ca²⁺、Al³⁺）和热处理对茶多酚绿色荧光特性的影响。结果表明：以上各因素对荧光强度的影响都极为显著,当溶液pH=7.4±0.2、茶多酚浓度为3βmg/ml或溶剂采用50%乙醇水溶液时,荧光强度达到最大值;金属离子（Ca²⁺、Al³⁺）的直接影响不明显,主要通过影响游离茶多酚浓度而降低其荧光强度;加热处理能显著增大荧光强度。当茶多酚浓度过高（>3βmg/ml）或pH>8时,能导致最大发射峰位置显著红移,其它因素对其影响较小;此外,溶剂极性显著地影响激发峰的形状和荧光强度,但对最大发射峰位置影响较小。     

紫外辐照对钝顶螺旋藻藻蓝蛋白的影响研究

近年来,富营养化带来的藻类尤其是蓝藻的大量繁殖引起水质恶化的情况越来越严重,如何控制藻类的大量繁殖日益受到人们关注。为此以钝顶螺旋藻为蓝藻代表,针对基于使用紫外光辐照抑制其生长的方法,对抑藻过程中藻蓝蛋白含量,纯度及结构的变化情况进行研究,探讨藻蓝蛋白在紫外辐照后的生理过程。结果发现,紫外辐照后7d内,钝顶螺旋藻中藻蓝蛋白的含量增加受到了有效的抑制,纯度也有所下降,藻蓝素的结构也发生了明显改变,从而从机理上对紫外抑藻的效果作出了初步解释。