杨盘二孢菌诱导的杨树差异表达基因的功能分析和染色体定位

利用cDNA芯片技术从含有2,952个克隆的杨树芯片中筛选出1,160个受杨盘二孢菌诱导的基因。功能分析表明,该1,160个基因分别属于11个功能类别,除了功能未知基因外,参与新陈代谢、防御反应、信号传导及转录调控的基因最多,这4大类基因约占基因总数的42%。1,160个差异表达基因中有926个基因被定位于19条染色体上,其中被定位于第Ⅱ条染色体上的差异基因最多,共102个(11.0%),其次是第Ⅰ条染色体,共93个(10%),被定位到第ⅩⅦ条染色体上的差异基因最少,仅有11个,基因在染色体上的分布则表现为在部分染色体的末端区域存在大量的聚集,在中间区段则相对较少和排列稀疏,基因的这种分布情况与植物抗病的关系有待进一步研究。     

Efficacy of triazoles and strobilurins in controlling black spot disease of roses caused by Diplocarpon rosae

Black spot disease is an important disease of roses with worldwide occurrence. It is caused by Diplocarpon rosae , an ascomycetous fungus and its control relies on fungicides. The effects of strobilurins and triazoles on D. rosae development within the host and on disease symptoms have not been well studied. Strobilurins completely inhibited germination of conidia when applied protectively 1 week before inoculation or on the same day with the inoculum. They were, however, not effective in eradicating the disease when applied after the fungus was established in the host. Triazoles reduced the germination rate of the conidia when applied protectively and they inhibited disease symptom development when applied after the fungus was established in the host but before symptom expression. Application of triazoles after symptom development suppressed further development of the disease, but in the case of treatment with myclobutanil yellowing and defoliation still occurred. Post-infection application of triazoles led to the apparent breakdown of subcuticular mycelia, intercellular mycelia, and hyphae in the epidermal cells, while the effects of strobilurins were limited to the subcuticular mycelia. Triazoles were more effective than strobilurins because they are more systemic.     

Detailed description of developmental growth stages of Diplocarpon rosae in Rosa: a core building block for efficient disease management

Black spot disease of roses caused by the ascomycetous fungus Diplocarpon rosae teleomorph (Marssonina rosae anamorph) is a widespread and devastating disease. Despite considerable progress in the management of black spot disease in the recent years, it is still unclear by which mechanisms this fungus colonises and invades the host system, and without a good knowledge of such infection machineries, it not possible to fully overcome the challenges of D. rosae infection. By exploring research contributions up to date, we highlight in this review the ultrastructure of D. rosae infection cycle in the host cell by emphasising on several aspects related to its in vitro and in vivo germinations, the infection mechanisms of the fungus, the different fungal structures formed in the host cells and the optimum storage conditions for D. rosae to retain its viability and pathogenicity over time. Here, attention is particularly focused on the asexual life cycle of D. rosae, with the sexual cycle being briefly discussed. In addition, a new dimension of research approaches to effectively control black spot disease of roses, that is, how to accurately use the advanced biotechnology tools to speed up the current state of the disease management, is proposed here.     

气象因素对陕西省苹果褐斑病流行的影响及预测模型

基于对1999-2008年陕西省气温、相对湿度以及陕西省苹果主产区苹果褐斑病发生、流行的监测,对苹果褐斑病发生时间、发病规律及流行程度进行了分析,并构建了旬平均气温(T)和旬平均相对湿度(Hm)影响下苹果褐斑病一维和三维动态预测模型.结果表明：研究区苹果褐斑病受环境因素影响严重,7、8月在田间扩展迅速并引起大量落叶,危害可持续至9月,初霜后不再有新病斑扩展;构建模型所用的T和Hm与田间实际条件基本一致,苹果褐斑病三维动态预测模型为：f(T,Hm)=-0.0172T³+0.9497T²-16.2209T+88.9923-0.00001Hm³+0.00354Hm²-0.15554Hm+2.36578［f(T,Hm)为病情指数］.模型结果表明,田间引起苹果褐斑病发生的T为15 ℃,大流行条件为7、8月T为 23 ℃、Hm在90%以上.     

美洲黑杨抗黑斑病基因的RAPD标记筛选和连锁分析

以美洲黑杨（Populus deltoides Bartr.cv.“Lux”(I-69/55)）为母本,欧美杨（P.euramericana cv.I-45）为父本得到的F1为材料,其中I-69对黑斑病表现为高度抗病,I-45为高度感病。利用分离群体混合分析（bulked segregrants analysis,BSA）技术建立两个DNA池（感病池和抗病池）,筛选出了与抗黑斑病性状基因相连锁的RAPD标记:OPAI17―1550、OPAI13―900。利用选择性基因型分析法进行标记―抗黑斑病基因连锁分析,两标记与抗黑斑病基因遗传距离分别为29.9cM和37.4cM。 Identification of Markers Linked to Resistance Locus of Marssonina Leaf Spot in Poplars by Bulked Segregant Analysis(BSA) ZHANG Bo1,HUANG Min-ren1,ZHUGE Qiang1,HAN Zheng-min1,YIN Tong-ming1,PAN Hui-xin1,ZHU Li-huang2,WU Rong-ling3,WANG ming-xiu１ 1.The Key Laboratory of Forest Tree Genetic Engineering,Nanjing Forestry University,Nanjing,210037,China; 2.The Institute of Genetics and Developmental Biology,Chinese Academy of Science,Beijing 100101,China; 3.Department of Statistics,University of Florida,Gainesville,Florida 32611,USA Abstract:DNA markers linked to resistance locus of Marssonina leaf spot in poplars were found by bulked segregant analysis(BSA).The bulks consisted of individual with a extreme phenotype taken from a population of 91 F1 clones,which is a progeny of Populus deltoides Bartr.cv.“Lux”(I-69/55)(Resistance) and P.euramericana cv.I-45(Susceptible).Out of 114 RAPD primers,four markers showed polymorphisms between the resistance-bulk and the susceptible-bulk.By using selective genotype linkage analysis,OPAI17-1550 and OPAI13-900 were found linked to the resistance locus.The genetic distances between the two markers and the resistance locus were 29.9cM and 37.4cM,respectively. Key words：BSA; RAPD; selective genotype analysis; Marssonina leaf spot     

寄生于龙眼上的两个腔胞纲真菌新种

本文报道寄生于龙眼Dimocarpus longan上的两个腔胞纲新种:龙眼盘二孢Marssonina dimocarpi 和龙眼叶点霉Phyllosticta dimocarpi,附有拉丁文简介描述及形态图,模式标本保存于广西大学农学院真菌标本室。     

冠盘二胞Marssonina coronaria侵染不同抗性苹果叶片的组织病理学研究

利用光学和电子显微镜,从组织细胞学水平系统研究了冠盘二胞Marssonina coronaria在苹果抗、感病品种叶片上的侵染过程及侵染后寄主细胞的超微结构特征。结果表明：冠盘二胞的侵入和定殖过程可以分为6个阶段：孢子萌发与芽管形成、附着胞形成、侵入细胞角质层、在叶肉细胞内产生吸器、菌丝在叶肉细胞间和细胞内扩展、分生孢子盘形成。随着菌丝扩展,受侵寄主细胞出现细胞壁加厚,细胞壁降解,质壁分离,叶绿体内淀粉粒、嗜饿颗粒积累,叶绿体基粒片层瓦解,线粒体空泡化等现象。在不同抗性的苹果品种上,分生孢子萌发率差别不明     

西北地区苹果褐斑病数学预测模型建立与分析

依据2001～2010年我国西北苹果主产区的气象数据与苹果褐斑病(Marssonina coronaria)病害发生流行数据,构建了平均气温(T)、相对湿度(Hm)、风速(Ws)及地表温度(St)影响下苹果褐斑病的流行趋势预测模型,并利用多元回归分析方法建立了苹果褐斑病预测模型.结果表明环境因素严重影响苹果褐斑病的发生和流行,苹果褐斑病预测模型为:f(T,Hm,Ws,St)=1.317T+0.002Hm+0.047Ws+0.001St-11.885[f(T,Hm,Ws,St)为病情指数].苹果褐斑病发生的T为14℃～15℃,Hm为45%,Ws为13m/s,St为10℃.大发生条件为T为20℃～23℃,Hm在70%～90%之间,Ws为0m/s～2m/s及St为22°.