多菌灵·氟硅唑防治贡柑炭疽病田间药效试验

为评价复配药剂37%多菌灵·氟硅唑可湿性粉剂防治贡柑炭疽病的效果及其对贡柑的安全性,连续两年进行了37%多菌灵·氟硅唑可湿性粉剂防治贡柑炭疽病的田间药效试验。试验结果表明,37%多菌灵·氟硅唑可湿性粉剂有效成分用量148、185和246.7 mg/L对贡柑炭疽病有较好的防治效果,施药3次后10 d调查,2014年的防治效果分别为71.90%、79.48%和90.16%,2015年分别为65.09%、76.18%和87.36%,该药剂值得在生产上推广应用。     

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。     

六种杀菌剂对柑橘炭疽病菌的室内毒力和田间防治效果

为了筛选高效、低毒、无公害的防治柑橘炭疽病（Colletotrichum gloeosporioides Penz.）的杀菌剂,采用菌丝生长速率法和孢子萌发法分别测定了吡唑醚菌酯、嘧菌酯、咪鲜胺、唑醚·代森联、甲基硫菌灵和丙森锌对柑橘炭疽病菌的室内毒力。室内测定结果表明：6种杀菌剂对柑橘炭疽病菌菌丝抑制的有效中浓度（EC50）分别为081,258,0066,497,1 55515和23798 μg·mL-1,吡唑醚菌酯、嘧菌酯、咪鲜胺和唑醚·代森联对该病孢子萌发EC50分别为093,1434,447和529 μg·mL-1。田间试验结果表明：嘧菌酯、咪鲜胺、丙森锌和唑醚·代森联在试验剂量下对炭疽病的防效在95％以上。综合室内外试验结果得知,嘧菌酯、咪鲜胺、丙森锌和唑醚·代森联是防治柑橘炭疽病的有效药剂。     

两种杀菌剂对油茶炭疽病的田间防效初探

油茶是我国重要的木本油料及造林树种之一,经济价值极高。炭疽病是危害油茶的主要病害之一,但目前尚未有登记的农药用于油茶炭疽病的防治。为筛选出安全、有效防治油茶炭疽病的杀菌剂,参照《农药田间药效试验准则杀菌剂防治茶饼病》,设计并开展此试验。结果表明,12.5%氟环唑悬浮剂有效成分41.67、62.5mg/kg.10%苯醚甲环唑水分散粒剂有效成分50mg/kg对油茶炭疽病均有较好防效,第2次药后20d的防效均高于70%。     

辣椒炭疽病抗性资源筛选

调查了46份辣椒(Capsicum annuum L.)材料对辣椒炭疽病(Collectotrichum sp.)的田间抗性表现.结果表明,19份材料对辣椒炭疽病有较强的抗性.以成都及近郊县的主要致病菌胶孢炭疽菌(Colletotrichum gloeosporioides)为接种菌源,采用针刺接种法对绿色成熟果(青熟果)和红色成熟果(红熟果)的23份辣椒资源进行辣椒炭疽病抗性筛选.结果表明,9份材料表现为抗病,6份材料表现为耐病,8份材料表现为感病.室内抗性筛选结果与田间抗性表现基本一致.     

草莓胶孢炭疽菌拮抗细菌贝莱斯芽孢杆菌JK3的鉴定及其抗菌活性

利用平板对峙法从堆肥中分离筛选到1株对草莓胶孢炭疽菌具有较强拮抗作用的细菌株系JK3。通过生理生化特征、16S rDNA和rpoB序列分析,将JK3菌株鉴定为贝莱斯芽孢杆菌。利用离体草莓叶片测定了JK3发酵上清液对草莓炭疽病的防治效果。结果显示:JK3发酵上清液对草莓胶孢炭疽菌引起的草莓炭疽病有明显预防效果,但治疗作用较差;提前24 h或接种胶孢炭疽菌孢子的同时喷施JK3发酵上清液,防治效果超过95%;接种胶孢炭疽菌孢子后24 h喷施发酵上清液,防治效果为11.5%。对JK3发酵上清液进行不同的温度、pH和蛋白酶处理,结果显示,发酵上清中的抑菌物质对pH和蛋白酶处理不敏感,但高温可降低其抑菌活性,推测主要抗菌活性成分不是蛋白质。由于芽孢杆菌多产生脂肽类抗菌物质,利用相关合成基因检测引物进行PCR扩增并测序,结果显示,JK3菌株含有脂肽类抗菌物质生物合成相关基因srfAA、bymB、fenD、bacA和ituC。以上结果表明,贝莱斯芽孢杆菌JK3有开发为防治胶孢炭疽菌引起的草莓炭疽病的生防制剂潜力。     

云南河口地区香蕉炭疽病的发生危害动态研究初报

依据河口县的地形地貌特征,分东部、西部及中南部并采用定点监测、分级调查法对香蕉炭疽病的发生危害动态进行研究。结果表明：香蕉炭疽病在河口地区1～3月基本维持较低的危害水平,4月初开始发病,8～12月中旬处于危害的高峰值,12月份后逐渐下降;全年月平均危害率达38.44%,月平均危害指数0.81,处于危害率较高的水平;西部地区与东部、中南部地区的差异达到显著水平,月平均危害率西部地区(49.61%)＞中南部地区(35%)＞东部地区(30.72%);不同海拔对香蕉炭疽病的田间发生危害有一定影响, 但未达显著水平     

Phylogenetic and morphological identification of Colletotrichum boninense: a novel causal agent of anthracnose in avocado

In recent years, anthracnose has become a significant disease affecting avocado fruit in the state of Michoacan, Mexico, where it significantly reduces fruit quality and commercial yield. Anthracnose has been assumed to involve Colletotrichum gloeosporioides and C. acutatum as causal agents. However, because of the increasing incidence of anthracnose, a more precise identification of the Colletotrichum spp. involved in this disease has become desirable. During the years 2004–2007, avocado fruits of different sizes exhibiting brown‐black and reddish spots on the pericarp and soft rot in the mesocarp, were gathered from orchards in nine counties. Fungal isolates were cultured on potato dextrose agar, and among these, 31 were selected for molecular, morphological and pathogenicity analyses. The molecular approaches used sequence typing of the internal transcribed spacer region and the partial nuclear large ribosomal subunit, allowing the unequivocal identification of C. gloeosporioides (71%), C. acutatum (16%) and C. boninense (13%). This last species has not been previously reported as being associated with anthracnose symptoms in avocado fruits anywhere in the world. Various morphological characteristics such as the size and shape of conidia were determined, as well as the conidial mass colour. Pathogenicity tests performed with all three species were conducted by inoculating healthy fruits. In each case, identical symptoms developed within 3 days of inoculation. Knowledge of the Colletotrichum populations in the Michoacan state, including the newly encountered avocado pathogen C. boninense, will facilitate further studies addressing the relationships between these Colletotrichum spp. and their avocado host.     

草莓抗炭疽病遗传图谱及其QTL初分析

为获得与草莓炭疽病密切相关的分子标记,需构建高密度与抗病相关的遗传连锁图,本研究以易感草莓炭疽病品种宝交早生（Hokowase）与高抗草莓炭疽病品种甜查理（SweetCharlie）杂交的210个F2代群体材料为作图群体,构建了包含34个AFLP标记和109个SSR标记的分子遗传图谱,并对抗草莓炭疽病相关因素进行了QTL分析。该图谱共包括7个连锁群和133个遗传标记,平均每个连锁群有19个遗传标记。遗传图谱总覆盖长度为451．8cM,标记间平均距离为3．4cM。经复合区间作图法分析得到3个与草莓炭疽病抗性相关基因座（QTL）,其中2个与Colletotrichumacutatum抗性相关,分布在LG3和LG5连锁群上,可解释表型变异的31．6％;1个与Colletotrichumgloeosporioides抗性相关,分布在LG6连锁群上,可解释表型变异的68．4％。     

BTH诱导橡胶抗炭疽病效果初探

用化学诱导剂BTH(benzothiadiazole)处理橡胶叶片后,再接种橡胶炭疽病菌,以研究BTH诱发橡胶对炭疽病产生系统性抗性的能力。结果表明,用BTH处理古铜期橡胶叶片后,橡胶炭疽病的病情指数较对照显著降低,BTH诱发橡胶叶片对炭疽病产生抗性的最佳浓度为200 mg/L,处理后7 d表现出最佳诱导抗性。说明BTH可以诱导橡胶对炭疽病产生系统获得抗性,并可用于田间炭疽病防治。