迷人杜鹃和马缨杜鹃杂交种愈伤组织的诱导方法

杜鹃花新品种的培育需要时间较长,而从自然界中选择自然杂交种来培育,能够节省许多时间。贵州百里杜鹃自然保护区内马缨杜鹃和迷人杜鹃自然杂交的后代能产生更多花色,具有一定的观赏价值和研究价值。本试验以贵州省百里杜鹃景区迷人杜鹃与马缨杜鹃杂交种的花苞、芽、茎段和根为材料,筛选了一种诱导迷人杜鹃和马缨杜鹃杂交种的愈伤组织的方法。结果表明:最佳消毒方法为0.1%的升汞浸泡8 min,期间不断搅拌的方式对外植体进行灭菌处理,之后用无菌蒸馏水冲洗4~5次,当选择使用1/2WPM+1.0 mg/L ZT+2.0 mg/Lα-NAA+100 mg/L的水解酪蛋白+30 g/L蔗糖+8 g/L琼脂粉,pH值为5.0的培养基时,迷人杜鹃与马缨杜鹃杂交种的愈伤组织长势最好。本研究结果为迷人杜鹃与马缨杜鹃杂交种的无性繁殖奠定了理论基础,为解决杂交品种后代性状不稳定以及繁殖问题提供了一种行之有效的方法,以期为杜鹃的种质资源保护、新品种选育、扩大繁殖和推广应用提供依据。     

β-罗勒烯信号传导途径关键基因突变体的筛选

罗勒烯作为一种植物通讯信号分子可以诱导植物的整体防御反应,但是目前对β-罗勒烯信号传导途径上的关键组分并不清楚。为了找到β-罗勒烯信号传导途径关键基因的突变体,本研究采用正向遗传学的方法,以带有PDF1.2pro::Luciferase和PR1pro::Luciferase表达框的转基因拟南芥为背景材料(M0),选用0.2%(v/v)EMS浓度构建了诱变群体,通过荧光素酶-荧光素活体荧光成像系统检测荧光表型来筛选突变体,成功筛选出了经β-罗勒烯诱导不发荧光的PDF1.2pro::Luciferase突变体植株(Ef)12株和PR1pro::Luciferase突变体植株(E1)10株,并在M2代确定了稳定不发荧光的表型。M3代检测β-罗勒烯信号途径下游基因PDF1.2与PR1的表达,以及测序验证突变体植株PDF1.2pro::Luciferase和PR1pro::Luciferase表达框的完整性,最后确认获得了与β-罗勒烯信号传导途径相关的可靠突变体的Ef材料为8株,E1材料为3株,为进一步探明β-罗勒烯信号传导途径的关键组分及其机制提供依据。     

Immune responses and protective efficacy of outer membrane protein ExbB of Pseudomonas fluorescens against Aeromonas hydrophila and Pseudomonas fluorescens affecting Carassius auratus

The outer membrane protein (ExbB) of Pseudomonas fluorescens present in the outermost layer may possess immune functions and potential applications in subunit vaccines. ExbB bioinformatic analysis elucidated that the relationship among Pseudomonas species was closer than others, and anti-ExbB serum might provide cross-protective ability to resist Pseudomonas bacterial infection in animals. ExbB was obtained via molecular cloning, prokaryotic expression, and purification. The optimal expression conditions were a strain OD₆₀₀ value of 1.0 and IPTG concentration of 0.3 mmol/L, inducing time of 3 h, and inducing temperature of 32℃. Mice immunized to ExbB could significantly increase (p?<?0.05) the spleen index and leukocyte phagocytosis parameters such as phagocytic percentage (PP) and phagocytic index (PI). The specific antiserum titer (1:12,800) was obtained, which had an in vitro immune recognition effect on both P. fluorescens and Aeromonas hydrophila. Passive immunization results for anti-ExbB mouse serum to Carassius auratus showed that ExbB serum could significantly enhance PP (p?<?0.05) and PI (p?<?0.05). Moreover, the passive protective rate of anti-ExbB serum against P. fluorescens infection was 54% (p?<?0.05), and the passive cross-protective rate against A. hydrophila was 38.4% (p?<?0.05). Furthermore, the expression of immune-related genes such as IL-6, IL-8, IL-1β, and TNF-α was significantly decreased (p?<?0.05) in kidneys and gills after challenging with P. fluorescens, while the downward trend was not obvious after challenging with A. hydrophila. The trend changes of antioxidant-related factors such as malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) were not obvious after bacterial challenge. Interestingly, there was a significant reduction in the histopathological lesions in the kidney, spleen, and intestine of C. auratus challenged by P. fluorescens and A. hydrophila. Altogether, the results suggest that ExbB has an immune function in passive protection against P. fluorescens and passive cross-protection against A. hydrophila and can boost resistance to infection against the most dangerous bacterial pathogens infecting freshwater fish.

     

松材线虫入侵对浙江平湖地区松林植物群落功能的影响

使用样方法和每木调查法,对松材线虫入侵后不同比例的马尾松混交林与黑松混交林的胸径和材积生长量(变化率)、生物量等群落功能指标进行了调查分析。结果表明:就林分胸径和材积生长量而言,随着混交比例（感病树种株数占林分总株数）的减小,各功能指标受害后变化幅度就越小,表现出整个林分对松材线虫的抵抗能力就越强,在该研究中,5针5阔表现出最强抵抗力;此外,松材线虫的侵入改变了未受害时不同混交比例黑松林的胸径生长量、材积生长量的数量对应关系（纯林＞7针3阔＞6针4阔＞5针5阔）,马尾松林则无此现象;就胸径与材积生长变化率而言,松材线虫入侵后,黑松林的变化较马尾松林更明显,这说明黑松纯林抵抗松材线虫的能力比马尾松纯林弱;松材线虫的侵入加速了松林从纯林向针阔混交林,进而向顶级群落常绿阔叶林方向演替的步伐。      

安徽省水稻品种对水稻白叶枯病的抗性及白叶枯病小种鉴定

为明确安徽省白叶枯病菌小种组成及常用、备用品种对该病的抗性,用白叶枯病强毒性小种FuJ和YN24、中等致病力的安徽省优势小种AH以及弱致病小种YN7对安徽省常用及备用水稻品种进行人工接种鉴定;用鉴别品种IRBB5、IRBB13、IRBB3、IRBB14、IRBB2、R24对安徽的白叶枯病菌株进行鉴定.结果表明,有3.5％的品种抗FuJ,15.4％的品种抗YN24,29.8％的品种抗AH;安徽省白叶枯病菌小种有R2、R5和R8,其中R5为优势小种.抗AH的品种可以用于安徽的水稻生产;生产中应防止FuJ和YN24等毒性强的菌株传入.     

Regional astrocyte allocation regulates CNS synaptogenesis and repair

Astrocytes, the most abundant cell population in the central nervous system (CNS), are essential for normal neurological function. We show that astrocytes are allocated to spatial domains in mouse spinal cord and brain in accordance with their embryonic sites of origin in the ventricular zone. These domains remain stable throughout life without evidence of secondary tangential migration, even after acute CNS injury. Domain-specific depletion of astrocytes in ventral spinal cord resulted in abnormal motor neuron synaptogenesis, which was not rescued by immigration of astrocytes from adjoining regions. Our findings demonstrate that region-restricted astrocyte allocation is a general CNS phenomenon and reveal intrinsic limitations of the astroglial response to injury.     

常温常压提取蜂花粉内含物的电镜观察

报道如何在常温常压下提取蜂花粉内含物，并保持花粉产品不受污染。结果表明，应用仿生学原理，蜂花粉经生物加工技术处理之后，能够促使花粉的萌发孔萌发沟极度张开，其内含物可以在常温常压下，从萌发孔、萌发沟处释放出来，逐渐向提取溶剂中扩散。内含物释放后花粉粒成为空壳，提取液不需高温消毒灭菌，产品即能达到食品卫生标准要求。     

鲁西南地区蜂群越夏管理

东北三省的养蜂人都认为"蜂好养,冬难越",而鲁西南应该说是"蜂好养,夏难越"。原因就是这里的夏季不光炎热,而且缺少蜜源。现介绍鲁西南地区蜂群越夏管理方法:最好用新王带群(新王的培育是在刺槐流蜜期)。用新王带     

甘蔗生产模型初探——以糖分动态分析为例

通过计算机系统建立甘蔗生产模型从而快速掌握甘蔗的糖分动态,对优化管理甘蔗生产具有现实意义。本文对3个品种、3个播种期的甘蔗植株进行6次锤度取样,并对试验数据进行了统计分析。结果表明,同一品种不同播种期的甘蔗植株,其糖分大体上都是随株龄的增长而升高;而同一播种期不同品种的甘蔗植株,其糖分的变化主要是由品种的遗传性决定的。