The involvement of phenolics and phytoalexins in resistance of potato to soft rot

Summary Phenolics, for example chlorogenic, caffeic and ferulic acid, and phytoalexins, such as rishitin and phytuberin, were identified in potato tubers cv. Kufri Chandramukhi. The tissue of healthy tubers contained no detectable phytoalexins but did contain phenolics. The levels of these compounds were correlated with soft rot development. The rotting tissue either was free of these groups of compounds or had low concentrations. The wound periderm formed as a result of recovery from injury and infection contained high levels of the compounds. Much higher concentrations were detected at lower storage temperatures when oxygen supply was adequate. Antibacterial properties of the phenolics identified were tested againstErwinia carotovora which was inhibited by chlorogenic, caffeic and ferulic acids. The three phenolics were more effective together, in proportions in which they occurred in wound periderm, than individually. It was observed that none of these phenolics could inhibit pectolytic enzymes ofE. carotovora.     

核盘菌诱导后向日葵防卫及激素信号传导相关基因差异表达分析

为探讨向日葵抗菌核病分子机制,在已构建的核盘菌诱导向日葵转录组差异表达基因分析基础上,筛选了8个向日葵防卫相关基因和水杨酸（SA）、茉莉（JA）及茉莉酸-乙烯（JA/ET）信号途径中的关键调控基因进行了qRT-PCR诱导表达分析。结果表明,当核盘菌侵染向日葵时,向日葵防御酶基因表达量与对照相比均有显著的变化,超氧化物歧化酶（SOD）、过氧化物酶（POD）和谷胱甘肽-S转移酶（GST）基因在6h表达量分别为对照25.02、22.34和26.25倍;苯丙氨酸解氨酶（PAL）、过氧化氢酶（CAT）和查尔酮合成酶（CHS）基因也上调表达,表达量在12h均达到最高,分别为对照的23.89、24.23和24.89倍;β-1,3-葡聚糖酶（GLU）基因在0～6h下调表达,之后又迅速升高,24h表达量达到最高,为对照的23.66倍;几丁质酶（CHI）基因先是下调表达,12h后开始上调表达,36h时表达量达到最高,为对照的22.13倍。SA、JA及JA/ET信号途径中的调控基因与未经诱导的相比均有明显的转录水平变化,而且JA/ET途径“节”点基因PDF1.2和SA-JA“节”点基因NPR1、MPK4和EDS1也明显上调表达。研究结果表明核盘菌诱导激发了向日葵多种抗病信号传导途径及防御反应,暗示向日葵对核盘菌侵染响应的分子机制受到多基因网络系统的调控。     

The correlation between the endometrial integrins and osteopontin expression with pinopodes development in ovariectomized mice in response to exogenous steroids hormones

Background: The ovariectomized animals are good models to evaluate the effect of different steroid hormone treatments on implantation events and the pattern of integrin expression. Therefore, this study was performed to compare the expression of integrins and osteopontin (OPN) in correlation with pinopode development in ovariectomized mice endometrium which was subjected to steroid hormones. Methods: Ovariectomized mice were subjected to estrogen, progesterone and estrogen-progesterone hormones. Their uterine horns were evaluated for integrin expression by immunohistochemistry and real-time RT-PCR and for pinopode development by transmission and scanning electron microscopic studies. Results: No immunostaining for integrin and OPN molecules were detected in the endometrium of non-ovariectomized mice except in metestrus phase. The α4 and β1 integrin genes were expressed in all phases of estrous cycle. In ovariectomized mice, no reaction was detected in the endometrium of control, sham and estrogen-treated groups, but in both progesterone-treated groups, all examined genes were expressed. There was not any correlation between pinopodes and integrin expression in ovariectomized mice. Conclusion: The progesterone is more effective on endometrial integrin expression than estrogen and differences in the expression pattern of integrins reflect their important and different roles in embryo implantation. The pinopodes may have minor effect in mice implantation or have some delay in their expressions in ovariectomized mice which were subjected to exogenous hormones. Key Words: Endometrium, Estrogen, Integrin, Ovariectomized mice, Osteopontin (OPN)     

Genome-wide identification of TPS genes in sesame and analysis of their expression in response to abiotic stresses

Trehalose and its precursor, trehalose-6-phosphate, play critical roles in plant metabolism and response to abiotic stresses. Trehalose-6-phosphate synthase(TPS) is a key enzyme in the trehalose synthesis pathway. Hence this study identified TPS genes in sesame(Si TPSs) and examined their expression patterns under various abiotic stresses. Totally, ten Si TPSs were identified and comprehensively characterized. Si TPSs were found to be unevenly distributed on five out of 13 sesame chromosomes and...     

A specialist-generalist classification of the arable flora and its response to changes in agricultural practices

Background  

Theory in ecology points out the potential link between the degree of specialisation of organisms and their responses to disturbances and suggests that this could be a key element for understanding the assembly of communities. We evaluated this question for the arable weed flora as this group has scarcely been the focus of ecological studies so far and because weeds are restricted to habitats characterised by very high degrees of disturbance. As such, weeds offer a case study to ask how specialization relates to abundance and distribution of species in relation to the varying disturbance regimes occurring in arable crops.     

我国龙舌兰麻种质资源的研究现状及应用前景

综述了我国龙舌兰麻种质资源的种源概况，种源研究及利用情况，提出了进一步开展龙舌兰麻种源研究的意见。     

荔枝裂果原因及防治技术措施

通过对莆田市荔枝裂果的情况进行观察与研究，并通过田间防治实践，初步筛选并提出了荔枝裂果的原因和适宜当地的荔枝裂果防治方法，为大田防治提供技术参考。     

湖北省有机茶生产现状与开发思路

湖北省是我国产茶大省之一,在前几年大力发展名优茶取得显著成效后,目前根据市场需求,及时地提出了在全省大力发展有机茶。文章客观、准确地分析了全省有机茶生产的有利条件和存在问题,从实际出发,较为系统、完整地、提出了开发有机茶的思路。     

我国茶叶质量安全现状与控制

近年来我国的茶叶质量安全水平虽有所提高,但问题依然不少。本文对我国茶叶质量安全现状、问题及影响因素进行了剖析,并提出了提高我国茶叶质量安全水平的措施。     

甘蓝型油菜杂种及其亲本的基因差异表达分析

以一个正在大面积推广的超高产甘蓝型油菜(B.napus)华油杂6号及其亲本为材料,应用拟南芥cDNA芯片,分析杂种和亲本在子叶期的基因差异表达.结果表明,杂种和母本8086A之间,有45个上调的转录本和73个下调的转录本;杂种和父本7-5之间,有105个上调表达的转录本和126个下调表达的转录本.所有这些涉及改变的转录本中,来自父本的转录本数目明显多于来自母本的转录本数目;下调表达的转录本明显多于上调表达的转录本.上调转录本中存在较多的非基础代谢基因,这些基因可能对华油杂6号子叶期杂种优势的形成起重要作用.     

Expression of the herpes simplex virus type 2 glycoprotein D in baculovirus expression system and evaluation of its immunogenicity in guinea pigs

Background: Herpes simplex virus type 2 (HSV-2) is highly prevalent and major cause of genital herpes in humans. The life-long nature of infection and the increasing prevalence of genital herpes imply that vaccination is the best strategy for controlling the spread of infection and limiting HSV disease. HSV glycoprotein D (gD) is one of the most important viral immunogen which has an essential role in virus infectivity and induction of immune responses. Methods: HSV-2 DNA was extracted and used as template in polymerase chain reactions to amplify gD2 gene. The PCR product was confirmed by restriction enzyme analysis, cloned into a cloning vector and then sequenced. The Bac-to-Bac expression system was used to express HSV-2 gD in insect cells. The expressed protein was used as subunit vaccine to immunize guinea pigs after confirmation. Results: The expressed protein was confirmed with SDS-PAGE and Western-blot analysis. In Western-blot analysis, two major protein bands, with approximate molecular weights of 52-55 and 41-43 kDa corresponding to the glycosylated and non-glycosylated forms of gD2 protein, were observed, respectively. Immunization with the recombinant gD2 could elicit humoral responses in guinea pigs as measured by neutralization test and ELISA, and offered high protection against induced HSV-2 genital disease. Conclusion: The baculovirus expression of heterologous genes permits proper folding, post-translational modification and oligomerization in manners that are often identical to those that occur in mammalian cells. Expression of proteins under the control of the strong polyhedrin promoter, allowing high level protein production, can be used as subunit vaccine.     

茶园土壤污染和防治

1茶园土壤污染的主要途径1．1大气沉降物污染 随着工业发展和汽车增多，大气污染日趋严重，大气污染物的沉降对农田土壤会造成不同程度的污染，汽如车尾气中的铅排放散发到大气中然后沉降就会给公路沿线的茶园造成土壤铅污染。据张寿宝等研究，苏北某茶场建于1958年，母质为下蜀系黄土，原土壤铅含量较低，但茶园分布在公路干线两侧，车     

嵊州市茶叶加工环境现状及对策

茶叶的加工环境对茶叶的优质高效起着决定性的作用。本文针对嵊州市茶叶加工环境现状，归纳出三大特点，分析出五大成因，提出了优化改造的三大对策。     

水稻胚囊形成过程与分期

 利用改进的GMA半薄连续切片技术对水稻品种IR36胚囊形成和发育进行了研究。结果表明：a)大孢子母细胞减数分裂Ⅰ形成的二分体和减数分裂Ⅱ形成的四分体的各个子细胞的大小都是不均等的；b)单核胚囊的3次有丝分裂的方向都较为固定；c)极核发育过程有明显的形态特征变化；d)胚囊形成各阶段淀粉粒出现与否有规律性。根据IR36胚囊形成的特点，初步将水稻胚囊形成过程分为8个时期，即孢原细胞形成期、大孢子母细胞形成期、大孢子母细胞减数分裂期、功能大孢子形成期、单核胚囊形成期、胚囊有丝分裂期、八核胚囊发育期和胚囊成熟期。     

分子标记技术及其在茶树育种中的研究进展

综述了分子标记技术种类、原理和优缺点,以及近年来在茶树种质资源的鉴定、遗传多样性分析与种群分类、遗传稳定性分析、遗传图谱的构建、基因定位与辅助育种等方面的应用,并对今后茶树分子标记技术的发展进行了展望。     

茶园蜘蛛的发生特点和保护利用

根据田间系统调查和控制观察,阐述了茶园蜘蛛在害虫捕食性天敌的地位、猎捕方式、发生特点和保护利用策略与方法。     

蓖麻毒蛋白A链基因克隆与重复表达载体构建

利用降落PCR的方法,从蓖麻基因组DNA中克隆毒蛋白A链基因的560bp片段;利用一步法将该基因的2个正义片段和2个反义片段分别与pBI-121质粒连接,构建含该基因的正义重复和反义重复表达载体,为利用共抑制技术抑制蓖麻毒蛋白A链基因表达的研究奠定基础。     

大米加工增碎的可能因素及预防措施探讨

随着生活水平的提高 ,人们对大米口感的要求越来越严格。而大米中含碎率的高低是影响大米口感的主要因素之一。稻谷品质差、收割与干燥方法不当、贮藏温度不适宜、加工过程中的恶性循环都易产生碎米。米太容易碎了 ,产生碎米的地方也太多了。砻谷机碎米、碾米机碎米、抛光机碎米、提升机碎米、绞龙输送碎米等等现象经常发生。大米生产企业 ,在设备选型、原粮选购方面 ,必须把如何降低大米增碎率加以重点考虑。这对我们粮机设计制造者 ,在设备设计上如何降低增碎方面也提出了更高的要求。近几年来 ,我公司也一直将如何降低设备增碎率作为设计…