大棚草莓白粉病及其防治

大棚栽培草莓在象山县已有十余年历史 ,常年种植面积约 333 3ｈｍ2 ,由于连年种植 ,草莓白粉病逐年加重 ,已成为常发性病害。草莓发生白粉病后 ,一般减收 2 0 %～ 30 % ,重的达 50 %以上 ,甚至绝收 ,严重影响草莓的产量和品质。我们从 1997年开始对该病的发生规律及综合防治技术进行了调查研究 ,引进新的三唑类杀菌剂进行试用 ,积累了一些经验 ,初步总结如下。1　发病特点与消长规律草莓白粉病的病原为Ｓｐｈａｅｒｏｔｈｅｃａａｐｈａｎｉｓ(Ｗａｌｌｒ)Ｂｒａｕｎ ,称羽衣草单囊壳菌 ,属子囊菌亚门真菌。该病为低温高湿型病害 ,发生频率…     

几种药剂对草莓炭疽病的效果

采用菌丝生长速率法测定了48%波尔多液可湿性粉剂、50%咪鲜胺可湿性粉剂、40%福美锌可湿性粉剂和70%代森联干悬浮剂4种药剂对草莓炭疽病菌的室内毒力。结果表明,4种药剂对菌丝生长的EC50的大小顺序为:50%咪鲜胺40%福美锌70%代森联48%波尔多液,50%咪鲜胺的EC50为6.24 mg/L。并选取毒力较好的50%咪鲜胺可湿性粉剂和40%福美锌可湿性粉剂进行了田间药效测定,48%波尔多液可湿性粉剂作为对照。试验发现:50%咪鲜胺可湿性粉剂在田间的效果最好,其800 mg/L处理在田间2次药后7 d的防效达到了80.26%,与对照药剂48%波尔多液可湿性粉剂间存在显著性差异。     

保护地草莓白粉病综合防治技术

近年来莱西市保护地草莓面积不断扩大 ,已成为农民致富增收的重要产业 ,但草莓白粉病是草莓生产的重要病害 ,缺乏理想的防治方法 ,每年给草莓生产者造成很大损失 ,为解决这一难题 ,寻找防治此病的有效方法 ,于１９９９年开始在莱西市部分乡镇进行了为期２年防治研究和探索 ,取得较好效果 ,现总结如下 :１发病症状及规律１．１发病症状白粉病广泛发生于草莓的保护地栽培中 ,主要危害叶、果实、果梗 ,叶柄和葡匐茎上很少发生 ,发病初期叶背面局部出现薄霜似的白色粉状物 ,以后迅速扩展到全株 ,随着病势的发展加重 ,叶向上卷曲、呈汤匙状 ;花蕾…     

多抗灵防治草莓白粉病的田间试验

多抗灵是浙江省农科院新近研制的一种由不吸水链霉菌杭州变种 (Streptomycesahygroscopicusvar.hangzhouensis)产生的抗生素。研究证实 ,该抗生素毒性低 ,对多种农作物的真菌病害有效。为了有效地防治草莓白粉病 [Sphaerotheca aphanis(Wallr.) Brau],我们在浙江富阳、象山、丽水、镇海、奉化等地进行了多抗灵防治草莓白粉病田间药效及 80 0余亩次的大田示范试验 ,取得了满意的效果 ,现简报如下。1　材料与方法试验在浙江富阳江岭草莓大棚中进行 ,草莓品种为丰香。试验设 1 %多抗灵水剂 2 0 0、1 5 0、1 0 0倍 ;1 5 %三唑酮 (粉锈宁 )可湿…     

11个草莓品种对炭疽病的田间抗性表现

在田间自然发病条件下,对种植在北京市昌平区的11个草莓品种的炭疽病发生情况进行了调查和分析比较。结果表明：草莓同一品种的三个部位（叶片、叶柄和匍匐茎）对炭疽病的抗性表现不一致,除‘莫哈维’和‘叙利亚’叶柄的病情指数高于叶片和匍匐茎外,其他品种都是匍匐茎的病情指数最高,‘波特拉’匍匐茎的病情指数高达73。根据叶柄对炭疽病的表现,在所调查的草莓品种中,品种‘森格纳’表现免疫,‘甜查理’、‘阿尔比’和‘圣安德瑞斯’为高抗,‘本尼西亚’和‘波特拉’表现为抗病,‘叙利亚’为高感,其他品种为感病。     

7种药剂对草莓白粉病的防效测定

为寻找高效、安全的草莓白粉病防治药剂,在离体叶盘和田间活体植株上测定了7种杀菌剂对草莓白粉病的防效。结果表明,42.5%吡唑醚菌酯.氟唑菌酰胺SC 450 mL/hm2和50%醚菌酯WG 560 g/hm2处理对草莓白粉病的防治效果较好,3次药后田间防效均在88%以上。50%硫磺SC 3 750 mL/hm2和碳酸氢钾4 500 g/hm2处理对草莓白粉病的防效略高于80%。     

防治高原地区草莓炭疽病的药剂筛选试验

草莓引入西藏日喀则后,炭疽病是其主要病害,在当地发生严重。对防治草莓炭疽病的市售药剂进行快速筛选试验,比较了40%五氯硝基苯粉剂、70%(?)霉灵可湿性粉剂、250 g/L嘧菌酯悬浮剂和20%五氯·福美双粉剂对温室内草莓炭疽病的防效,发现40%五氯硝基苯粉剂1 000倍液喷施处理防效最高,第3次药后的病指校正防效达到81.9%,防效与速效性均优于其他供试药剂。     

保护地草莓白粉病的防治药剂筛选

河南信阳保护地草莓白粉病为害较重,并已出现抗药性问题。为探寻安全、有效的防治药剂,对75%肟菌.戊唑醇WG、50%醚菌酯WG、10%苯醚甲环唑WG、25%三唑酮WP、75%百菌清WP进行了药效筛选试验。结果表明,75%肟菌.戊唑醇WG 3 000倍液、50%醚菌酯WG 3 000倍液的防效较好,均在80%以上,与其他药剂的防效差异显著,且对草莓安全、无害,可以在信阳地区作为防治草莓白粉病的药剂推广应用。     

大棚草莓炭疽病绿色防治技术

草莓炭疽病是一种高温、高湿型真菌性病害,在郓城县大棚草莓生产上为害逐年加重。针对大棚草莓炭疽病发生的为害症状、发病规律,总结大棚草莓炭疽病绿色防治技术。     

几种杀菌剂对草莓白粉病的防效研究

在温室大棚用苯醚甲环唑、苯醚甲环唑+丙环唑、氟硅唑、腈菌唑和三唑酮等杀菌剂防治草莓白粉病Sphaerotheca aphanis。结果表明,适宜浓度的 10%苯醚甲环唑WG、30%苯醚甲环唑+丙环唑EC、40%氟硅唑EC、20%三唑酮EC、12.5%腈菌唑EC的田间防治效果均可达到80%以上;苯醚甲环唑、苯醚甲环唑+丙环唑、氟硅唑和三唑酮的持效期约为18 d,而腈菌唑的持效期较短,约为7 d。10%苯醚甲环唑WG在360~900 g/hm2用量时不影响草莓长势,而氟硅唑225 mL/hm2和三唑酮300~450 mL/hm2用量时则在不同程度上抑制草莓的生长。     

Suppressive effect of potassium silicate on powdery mildew of strawberry in hydroponics

From 1996 to 1997, potassium silicate (SiO₂) was tested at 0, 25, 50, and 100mgl^–1 in hydroponics to control powdery mildew. Other elements were added in the usual amounts, and the strawberries were cultivated hydroponically in a greenhouse for 4 months (from October to January). The powdery mildew spread in the control plot, but little mildew developed in the plot with 25mgl^–1 silicate, and none in plots with more than 50mgl^–1 silicate. The suppressive effect lasted for about 4 months on fruits and even longer on leaves. On analysis of mineral content in the leaves, only the silicate content differed markedly between the control and treated plants. Nitrogen, phosphate, potassium, and calcium contents did not differ greatly. The maximum silicate content was about 24 times that of the control, and disease severity decreased significantly when the content was more than 1.5% in the leaves. The hardness of the strawberry leaves, measured by a creep meter, was increased by the silicate treatment.     

Suppressive effect of liquid potassium silicate on powdery mildew of strawberry in soil

A soil drench of soluble silicon (liquid potassium silicate) was tested for the control of powdery mildew of strawberry in soil for 2 years in a vinyl house under growers' conditions on two cultivars: very susceptible Toyonoka and slightly susceptible Sachinoka. Soluble silicon suppressed the disease more effectively as a preventive control than as a control to reduce initial incidence. The suppressive effect against this disease was more effective for Toyonoka than for Sachinoka. The control value of soluble potassium silicate was 85.6% for Toyonoka in the first year and 60.2% in the second year, while for Sachinoka it was 58% in the first year and 40.6% in the second year. Strawberry leaf hardness was measured for the control and silicate-treated leaves. Although silicate-treated leaves seemed to be harder than control leaves, leaf hardness did not vary significantly between controls and silicate-treated leaves in either of the 2 years, and the mode of preventive action of liquid potassium silicate remains unknown. A factor other than a physical action may be involved.     

2%武夷菌素水剂对草莓白粉病的毒力测定及田间防效

武夷菌素是一种农用抗生素类生物杀菌剂,温室及田间试验表明它对粮食、蔬菜、果树上的多种真菌病害有很好的防治效果,并且已经应用于农业生产中.为了考查其对草莓白粉病的防治效果,进行了室内孢子萌发抑制试验,结果表明武夷菌素能够抑制草莓白粉病菌孢子的萌发,其EC50为9.550 6μg/mL.同时田间药效试验结果表明,2％武夷菌素水剂对草莓白粉病具有良好的防治效果,其300倍液防治草莓白粉病的效果和化学农药10％苯醚甲环唑水分散粒剂相当,武夷菌素200倍液的防效显著高于化学农药,同时对草莓自身的生长发育没有影响.试验表明武夷菌素对草莓白粉病有很好的防治作用,可为生产上防治草莓白粉病和科学用药提供依据.     

浙东大棚草莓白粉病菌越夏和初侵染菌源的研究

离体和盆栽试验表明,草莓白粉病菌经38℃高温处理8 h,分生孢子不能萌发;或每天38℃处理8 h,适温下16 h连续培养4 d后病斑不再产生分生孢子。据田间试验和调查,在浙江宁波夏季自然条件下繁育草莓苗,草莓白粉病菌不能存活到秋季,但当草莓生长良好或在有明显遮阳条件下繁育苗,少数病菌可以在草莓上越夏,越夏部位多在病株9月间仍保持绿色或部分绿色的原发病部位的匍匐茎段上。     

Suppression of conidial germination and appressorial formation by silicate treatment in powdery mildew of strawberry

The mode of action of soluble silicon against strawberry powdery mildew (Sphaerotheca aphanis var. aphanis) was investigated in four experiments. First, silicon-treated leaves from plants grown with silicate (Si+) and control leaves were excised, inoculated with conidia, and subsequent germination and formation of appressoria in a petri dish was assessed after 24 h. The germination rate was 49.7% on Si+ leaves, and was 67.2% on control leaves (t-test, P < 0.01). Second, we soaked cellulose membranes in various solvents and then placed the membranes on 4% water agar, dusted the membranes with conidia, and examined after 12 h. No difference was apparent between any treatment and the control (distilled water). Third, strawberries growing hydroponically with additional silicon in the medium were inoculated with conidia, and leaves were observed with a scanning electron microscope 1–2 days after inoculation. Germ tubes and secondary hyphae were shorter and had fewer branches on Si+ leaves than on the control. Moreover, penetration appeared to be inhibited. Fourth, the cuticle was separated from leaves from plants grown as in the third experiment, placed on water agar, and dusted with conidia. Germination of conidia, observed with a light microscope, on Si+ leaves was suppressed markedly to 40%–60% of that of the control. These results suggested that soluble silicon induced physiological changes in the cuticle layer after absorption by the plant. In addition, soluble silicate reduced germination of conidia, formation of appressoria, and possibly the penetration of powdery mildew.     

防治西葫芦和黄瓜白粉病的生物制剂的筛选

瓜类白粉病是蔬菜上的重要病害之一,为加大对该病害的生物防治力度,本研究采用课题组研发的1×109cfu/g玫瑰黄链霉菌水剂和10亿芽胞/g枯草芽胞杆菌悬浮剂以及市场上常用的枯草芽胞杆菌、哈茨木霉菌、寡雄腐霉、武夷菌素、多抗霉素等多种生物制剂进行田间药效试验,比较几种生物制剂的防治效果。结果表明,供试生物制剂对西葫芦白粉病的防效为57.65%~84.98%,其中3%多抗霉素水剂600倍液的防效最好,为84.98%,且具有明显的促生长作用,增产率达12.65%。其次为1 000亿芽胞/g枯草芽胞杆菌可湿性粉剂(武汉天惠)400倍液、2%武夷菌素水剂600倍液和3×108 cfu/g哈茨木霉菌可湿性粉剂300倍液,可作为西葫芦白粉病防治的选用药剂。1×109 cfu/g玫瑰黄链霉菌水剂对西葫芦和黄瓜白粉病均具有较好的防效,分别为78.68%和73.59%,具有开发和应用的市场价值。     

Effect of temperature on infection and development of powdery mildew on cucumber

Podosphaera xanthii and Golovinomyces orontii are the causal agents of cucurbit powdery mildew. The effect of temperature on conidial germination, infection and sporulation was studied under controlled conditions. Conidia were inoculated on cucumber leaf discs, and incubated at six constant temperatures (from 10 to 35 °C in 5 °C steps) for 3 to 72 h to evaluate conidial germination and infection, and for 6–15 days to evaluate sporulation intensity. Germination took place at all tested temperatures, but was close to zero at 35 °C. The longest germ tubes measured in this experiment were 141.74 μm for the secondary germ tube of P. xanthii at 20 °C after 48 h of incubation, and 67.92 μm for G. orontii for the primary germ tube at 20 °C after 48 h of incubation. The optimal temperatures for conidial germination, infection and sporulation were 24.4, 25.7 and 22.3 °C, respectively, for P. xanthii, and 17.9, 17.3 and 14.9 °C, respectively, for G. orontii. Equations were developed to describe conidial germination with a coefficient of determination (R²) of 0.85 and 0.90 for P. xanthii and G. orontii, respectively. Infection equations resulted in R² of 0.94 and 0.93 for P. xanthii and G. orontii, respectively; and for sporulation, R² of 0.75 and 0.76 for P. xanthii and G. orontii respectively, as a function of temperature. These results can be used to develop models for the risk of cucurbit powdery mildew under field conditions.     

Effect of seventeen fungicolous fungi on sporulation of cucumber powdery mildew

Nineteen isolates of 17 different fungal species thriving upon other fungi were tested for their ability to control sporulation of cucumber powdery mildew,Sphaerotheca fuliginea. More than half of the fungi reduced the number of healthy conidiophores to less than 10%.Tilletiopsis albescens was superior toAmpelomyces quisqualis. Three species, viz.A. quisqualis, Aphanocladium album andT. albescens, were selected for further greenhouse experiments.Samenvatting Negentien isolaten behorend tot 17 verschillende schimmelsoorten werden getoetst op hun bruikbaarheid voor de biologische bestrijding van komkommermeeldauw aan de hand van effecten op sporulatie. Meer dan de helft van de getoetete isolaten reduceerde het aantal gezonde conidioforen tot minder dan 10%. De werking vanTilletiopsis albescens was enigszins beter dan die van de meestal gebruikte hyperparasietAmpelomyces quisqualis. Van de getoetste schimmels werden er drie, n.l.A. quisqualis, Aphanocladium album enT. albescens, geselecteerd voor kasproeven.     

Effect of flutianil on the morphology and gene expression of powdery mildew

Flutianil, a fungicide effective only on powdery mildew, was previously reported to affect the host cell''s haustorial formation and nutrient absorption. Studies were conducted to investigate flutianil''s primary site of action on Blumeria graminis morphology using transmission electron microscope (TEM) observation and RNA sequencing (RAN-seq) techniques. TEM observation revealed that flutianil caused the extra-haustorial matrix and fungal cell wall to be obscured, without remarkable changes of other fungal organelles. RNA-seq analysis indicated that, unlike other powdery-mildew fungicides, flutianil did not significantly affect the constantly expressed genes for the survival of B. graminis. Genes whose expression is up- or downregulated by flutianil were found; these are the three sugar transporter genes and various effector genes, mainly expressed in haustoria. These findings indicate that the primary site of action of flutianil might be in the haustoria.