木薯细菌性枯萎病菌转座子库的构建及其质量评价

猫豆是广西种植的一种特色药用植物,近年来发生一些重要病害,为明确这些病害种类,对广西猫豆主产区进行主要病害种类调查和病原鉴定.每块地采取5点取样法进行取样调查,并通过形态特征和rDNAITS序列分析结果对病原菌进行鉴定.研究结果发现,猫豆上发生的主要病害有4种,分别为猫豆炭疽病(Colletotrichum gloeosporioides)、猫豆茎溃疡病(Phomopsis sp.)、猫豆斑枯病(Alternaria sp.)和猫豆褐斑病(Pseudocercospora sp.),这些病害的发病率达30％ ～80％.     

海南岛槟榔根部及茎部病害调查及病原鉴定

在2003￣2005年间对海南省儋州、澄迈、琼山、文昌、陵水、琼海、万宁、保亭、琼中、五指山、白沙、三亚、乐东等13个市(县)的部分槟榔园内发生的槟榔根部及茎部病害进行了调查与病原鉴定。共调查到海南岛槟榔茎腐及根腐病害及附生植物6类21种。其中真菌病害8种,非侵染性病害4种,地衣类3种,附生蕨类植物4种,寄生植物病害1种,病原未明病害1种(丛枝病)。其中能引起槟榔全株枯死的病因有2类12种,真菌8种,非侵染性病因4种。     

福建枫香炭疽病病原的种类鉴定

在调查福建霞浦杨家溪榕枫公园和福州森林公园的枫香树叶部病害过程中,分离得到了6株形态特征有差异的炭疽菌,并采用形态特征与多基因位点系统发育分析相结合的方法对其进行鉴定。形态特征包括菌落性状、分生孢子盘、分生孢子梗及分生孢子等;系统发育分析包括内转录间隔区（ITS）、β-微管蛋白（TUB2）、肌动蛋白（ACT）、3-磷酸甘油醛脱氢酶（GAPDH）和几丁质合成酶（CHS-1）5个基因。研究明确了这6个菌株可鉴定为炭疽菌的3个种,即胶孢炭疽复合种中的果生炭疽菌C. fructicola和热带炭疽菌C. tropicale,以及尖孢炭疽复合种中的松针炭疽菌C. fioriniae。经柯赫氏法则的验证,这3个炭疽菌种均可引起枫香炭疽病,但致病力有所不同。这也是C. fructicola、C. tropicale和C. fioriniae引起枫香炭疽病的首次报道。     

富裕县豆田主要蝗虫种类及防治

经调查,富裕县蝗虫有2个总科、7个科、12种,按发生时间划分为早生型和晚生型2类。在豆田以晚生型的大垫尖翅蝗和中华稻蝗混合发生为主,大垫尖翅蝗为优势种群。在防治上,应重视综合治理,大发生时以化学药剂防治为主,一般年份以农业防治为主。     

甘肃大麦、青稞病害调查及病原鉴定

3年来 ,对我省武威、玉门、甘南等 12个县市、16个单位、乡、农场的试验田、大田进行了调查及室内镜检、培养。共鉴定大麦病害 2 4种 ,计有真菌性病害 18种 ,细菌性病害 1种 ,病毒病害 5种。其中有 9种为省内首次记录 ,2种为国内首次记录。     

海南降香黄檀炭疽病病原鉴定及防治

针对海南降香黄檀炭疽病的病原进行研究,结合危害症状、病原菌的菌落形态以及分生孢子特征等将海南降香黄檀炭疽病病原鉴定为胶孢炭疽菌Colletotrichum gloeosporioides(Penz.) Sacc.,并提出一些防治措施。     

甘肃大麦、青稞病害调查及病原鉴定

3年来，对我省武威、玉门、甘南等12个县市、16个单位、乡、农场的试验田、大田进行了调查及室内镜检、培养。共鉴定大麦病害24种，计有真菌性病害18种，细菌性病害1种，病毒病害5种。其中有9种为省内首次记录，2种为国内首次记录。     

棉花苗期主要病害与防治方法

棉花苗期主要病害有炭疽病、立枯病、褐斑病、红腐病等,其中炭疽病和立枯病发生比较常见,对棉苗的危害也最严重.     

低温贮藏对班氏跳小蜂寄生率及繁殖力的影响

班氏跳小蜂(A enasius bambawalei Hayat)是扶桑绵粉蚧(Phenacoccus solenopsis Tinsley)的优势寄生蜂.本文在温度(10±1)℃、RH (70±5)％和L:D(12:12)的条件下,分别对被寄生的扶桑绵粉蚧僵蚧、不补充营养的班氏跳小蜂雌蜂、补充10％蜂蜜水的班氏跳小蜂雌蜂进行低温贮藏,研究其对跳小蜂寄生率及繁殖力的影响.结果表明:不补充营养的班氏跳小蜂的贮藏期以2d为适;补充10％蜂蜜水班氏跳小蜂雌蜂的贮藏期以6d为宜,被寄生的扶桑绵粉蚧僵蚧的贮藏期可延长到10d.试验结果可为班氏跳小蜂的大量扩繁及田间应用提供参考.     

橡胶树新发茎杆溃疡病病原鉴定及其生物学特性测定

2014至2015年,对海南省橡胶树主栽区的病害普查中发现1种新的茎杆溃疡病。该病在海南省部分农场发生严重,为害中小龄胶树和开割树的茎杆,造成树皮隆起并呈褐色,严重时流出白色胶乳,对橡胶树的长势和产胶量造成重要影响。通过形态观察、rDNA-ITS序列比较和聚类分析结果表明,分离自不同地点的8株病原菌均为茄类镰刀菌(Fusarium solani)。菌株HHNBS01的生物学特性表明,CMA、PDA和Czapek培养基中,以蔗糖和硝酸钾为碳源和氮源,30℃,pH6为菌落生长最适条件,15℃,pH6,完全黑暗,D-木糖和草酸铵分别为碳源和氮源是产孢最适条件,30℃,pH7为分生孢子萌发最适条件,而菌丝和分生孢子的致死温度均为60℃10 min。     

木薯新发藻斑病在中国的发生调查及病原鉴定

2010~2015年,笔者在对中国木薯主栽区的病害调查中发现了一种新的叶斑病。该病在云南、海南、广西、江西、福建等地区均有发生,生长中后期爆发流行,初步分析低温是该病成灾的关键因子。病原在叶片上形成黄褐色或黑褐色、近圆形、中央灰白色毛毡状的病斑,发病叶片大量脱落,严重影响木薯的长势和产量。对来自不同地区的病样进行显微观察。结果表明:病原在寄主组织上均形成有隔的孢囊梗,单生或丛生,其上着生数个圆形、黄色的孢子囊,表明其为寄生性头孢藻。     

Effect of Detarium microcarpum (Dm) and Mucuna flagellipes (Mf) gums on the quality of white bread

Incorporation of Detarium Microcarpum (Dm) and Mucuna flagellipes (Mf) water soluble polysaccharides (gums) at 0.0 to 0.5% levels in wheat flour was studied to evaluate their effect on the rheological properties of wheat flour dough and white bread quality. At all levels of incorporation, there were increases (p 0.05) in water absorption of the dough. Doughs containing gums had higher (p 0.05) mixing tolerance index than the control. Set back viscosities decreased by 4.0 RVU and 9.0 RVU with increased levels of Dm and Mf gum incorporation, respectively. Significantly (p 0.05) higher oven spring occurred in all the gum substituted white bread when compared to the control. The 0.5% gum substituted breads had a significantly (p 0.05) higher sensory score for crumb grain, texture but lower (p<0.05) crumb firmness than the control as determined instrumentally. Textural analysis after 5 days storage revealed that Dm and Mf gums improved moisture retention properties of the bread and reduced crumb firming tendency.     

中国木薯白点病发生调查及病原生物学特性研究

2007—2018年,本课题组在对中国木薯主栽区的病害调查中发现了一种国内尚未记载的叶斑病。病害主要危害叶片,形成圆形或不规则形、常密集分布的白色至黄褐色的病斑,故命名为白点病。该病在云南、海南、广西等地区均有发生,绝大多数主栽品种和部分新育成种质均受害。经病菌分离和回接实验以及病菌形态观察、核糖体基因间隔区和β-微管蛋白基因序列分析,将该病病原鉴定为链格孢(Alternaria alternata)。病菌离体培养实验表明,菌丝生长最适条件为V9、OA、CA或CMA培养基,28℃,D-麦芽糖、D-山梨醇或D-乳糖,硝酸钠,光暗交替,pH8。分生孢子萌发最适温度为28℃,而致死温度为60℃处理5min。杀菌剂敏感性测定结果表明,在所测试的10种药剂中,10%苯醚甲环唑WG和25%吡唑醚菌酯WG的EC50值分别为0.12、0.47 mg/L,对菌丝生长抑制率最高。     

纹枯病菌对不同水稻品种叶片中抗病性相关酶活性的影响

对优质抗纹枯病水稻品种ZH5、较抗纹枯病品种特青、感纹枯病品种Lemont及恢复系泸恢17、多系1号和GB8等水稻材料进行纹枯病菌接种,测定了水稻叶片中与抗病性相关的超氧化物歧化酶 (SOD)、过氧化物酶 (POD) 的活性和丙二醛 (MDA) 的含量。不论纹枯病菌接种与否,ZH5和特青叶片中SOD活性均明显高于Lemont;纹枯病菌接种后,抗性品种ZH5和特青叶片中POD活性升高,感病品种Lemont 叶片中POD活性降低;不论是抗病还是感病的水稻材料,纹枯病菌接种后叶片中MDA含量均有所增加,但ZH5叶片中MDA含量明显低于其他参试材料。     

Association Between Seed Coat Polyphenolics (Tannins) and Disease Resistance in Common Bean

Common beans (Phaseolus vulgaris L) contain a number of antinutritional factors such as condensed tannins. Reducing tannin concentration might contribute to improving the nutritional quality of common bean. But polyphenolics are involved in resistance to diseases and pests, and reducing tannin concentration may have a negative effect on plant resistance. Furthermore, the effects of tannin on disease resistance in different gene pools or in different seed colors are not defined. To investigate these effects, 790 accessions from a common bean core collection were investigated. Data were subjected to independent sample t-tests, and the calculation of correlation coefficients. The mean coat extracts of black and red bean classes were highest (with 0.129 g/g and 0.124 g/g of seed coat, respectively). Among the gene pools, the coat extract was greater in the Middle American gene pool (0.129 g/g) than in the Andean gene pool (0.108 g/g). Coat extract in the Andean gene pool was positively correlated with susceptibility to Middle American isolates of anthracnose and to common bacterial blight, but negatively correlated with susceptibility to Andean isolates of angular leaf spot and to empoasca. Only empoasca damage showed negative correlation with coat extract in the Middle American gene pool. However within gene pools, the coat extracts of different seed classes varied in correlations with reactions to disease and pest infestations. Significant correlations were particularly associated with the black seed class in both gene pools. The relationships between coat extract and disease reactions are complex. A better understanding will help breeders to select germplasm with improved nutritional quality without adversely affecting disease resistance.     

Identification and characterization of Didymella bryoniae causing gummy stem blight disease of watermelon (Citrullus lanatus) in Turkey

Watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai) is an important plant in the family Cucurbitaceae. Didymella bryoniae (Auersw.) Rehm [anamorph Phoma cucurbitacearum (Fr.) Sacc.] is the causative agent of gummy stem blight (GSB), a disease affecting members of the family Cucurbitaceae. Watermelon seedlings showing varied degree (20–90%) of suspected GSBs were collected from seedling companies in Antalya province, Turkey. The symptoms included angular water-soaked lesions, which turned tan over time; defoliation; dry, pale green stem; stem necrosis; gummy exudates; wilt; and the eventual death of the upper parts of the seedling plants. The growth of the fungal isolate in vitro showed white aerial and olivaceous mycelium, and olive to dark green or black substrate mycelium at the latter period of fungal growth. The colony surface was rough and undulated. The conidia were round-ended, cylindrical, monoseptate, and hyaline. The conidia ranged from 6.4 to 13.6 μm in length and 3.69–4.68 μm in diameter. The isolates were subjected to PCR using three primers, namely, DB-F3/DB-R3, GSBF1/GSBR1, and ITS1/ITS4, which produced fragment sizes of approximately 120, 780, and 560 bp, respectively. The real-time PCR using DB-F3/DB-R3 primer and SYBR Green fluorescence dye produced positive result for the samples tested. The D. bryoniae isolate was pathogenic to all the four different cucurbits tested and were consistently re-isolated from the diseased seedlings confirming their pathogenic status and thereby satisfying Koch's postulates. This is the second report confirming the presence of D. bryoniae in Turkey after its first detection in cucumber in 2015.     

广西阳朔县重点药用植物资源现状的调查与分析

在第四次全国中药资源普查工作中,采用查阅文献、样线和样方相结合的调查方法,对阳朔县药用植物资源的种类、分布及蕴藏量等进行调查和统计分析。结果表明：（1）本次调查和鉴定,阳朔县共有野生和栽培药用植物919种（包括种下单位）,隶属于160科527属;其中野生重点调查药用植物70种,栽培重点调查药用植物6种,国家Ⅰ级保护植物1种,国家II级保护植物7种,广西重点保护植物8种。（2）对样方调查中发现的57种野生重点药用植物的出现频率和蕴藏量进行统计,其中60.00%的物种蕴藏量小于100 t,野生重点中药材总蕴藏量11 610.18 t;66.67%的物种出现频率低。可见,阳朔县药用植物资源丰富,珍稀濒危保护植物种类多,生态环境保护较好;但各物种的出现频率和蕴藏量差异大,很多物种野生资源稀缺,对部分药用植物的保护已刻不容缓;建议把旅游业与中药种植业相结合,保护自然景观与生态环境,确保经济与生态协调发展。     

Identification and characterization of Colletotrichum fructicola causing black spots on young fruits related to bitter rot of pear (Pyrus bretschneideri Rehd.) in China

In recent years, Pyrus bretschneideri Rehd. var. ‘Suli’ has been damaged by a disease characterized by the presence of black spots on young fruit in China, which was always followed by severe bitter rot on matured fruits. The etiology of these symptoms and their relationship with the bitter rot was unknown. A colony was routinely isolated from young and matured ‘Suli’ pear fruits showing black spots and rot symptoms, respectively. This fungal colony was identified as Colletotrichum fructicola based on morphological characteristics and DNA sequence data of 7 regions. C. fructicola was confirmed to be capable of eliciting both black spots and bitter rot symptoms by completion of Koch's Postulates. The results suggested that the disease characterized by the presence of black spots on young fruits is indeed an early stage of the bitter rot observed on matured fruits of ‘Suli’ pear. Variety resistance analysis indicated an obvious resistance variation possessed by the pear varieties generally cultured in China, with black spots only occurring on some pear varieties. Our results also indicated that wounding can break the quiescent infections, enhance the infectivity of C. fructicola, and lead to more rapid rot of young and matured fruits. These results provided a clear clue that C. fructicola can invade some varieties of P. bretschneideri Rehd. directly without entry via wounds, but subsequently turned into quiescent infection and causing black spots on the fruit surface. The quiescent infection acts as a pathogenic factor responsible for bitter rot of matured fruits. The influence of temperature and pH conditions for growth and colony morphology of C. fructicola were also evaluated. The characterization of C. fructicola causing bitter rot of pear (P. bretschneideri) is expected to provide useful information for controlling this economically important disease.