Variations of phyllosphere microorganisms in asymptomatic and tobacco brown spot leaves before and after spraying 12% difenoconazole + fluxapyroxad SC

12%difenoconazole+fluxapyroxad SC(commercial name:Jiangong)was first released by BASF in China in 2016.It has been registered to control many diseases,including pear scab,apple Alternaria leaf spot,tomato early blight,cucumber powdery mildew,etc.This study evaluated the bioactivity of Jiangong against Alternaria alternata and explored variations of phyllosphere microorganisms in both asymptomatic and tobacco brown spot leaves at different persistence periods(0,5,10,and 15 days post-fungicide application)using high-throughput sequencing technology.The results indicated that Jiangong effectively inhibited mycelial growth(average EC_(50) value of 0.51μg/mL),conidia germination(average EC_(50) value of 3.47μg/mL),and the carbon metabolism of A.alternata.Both asymptomatic and symptomatic leaves presented complex microbial communities.Higher fungal diversity was noted in asymptomatic leaves,while higher bacterial diversity was found in symptomatic leaves.After application,the diversity and abundance of microbial community structures in both types of leaves changed over time.Fungal microbiome communities showed greater sensitivity than bacterial groups,with the microbiome communities of asymptomatic leaves being more affected than those of symptomatic leaves.Fungal community diversity decreased for both symptomatic and asymptomatic leaves after 5 days of application,while the diversity of fungal community in symptomatic leaves showed an upward trend after 10 days of application.Meanwhile,bacterial community diversity increased in both symptomatic and asymptomatic leaves after 5 days of application but then declined in asymptomatic leaves after 15 days.The abundance of the dominant function group of phyllosphere bacteria(metabolism,genetic information processing,environmental information processing)was not affected by the application of Jiangong.However,the abundance of the dominant function group of phyllosphere fungi(animal pathogen-endophyte-wood saprotroph,endophyte-plant pathogen,plant pathogen-undefined saprotroph)was significantly affected by the application of Jiangong,and high variation was found in symptomatic leaves than that of asymptomatic leaves.The application of Jiangong-induced alterations in the community structure of the tobacco phyllosphere microbiome provides a basis for future tobacco brown spot control strategies based on phyllospheric microecology.

Evaluation of Resistance of Different Kiwifruit Varieties (Lines) to Canker Disease and Brown Spot Disease

Kiwifruit canker and brown spot are significant diseases affecting kiwis,caused by Pseudomonas syringae patho-genic variations(Pseudomonas syringae pv.Actinidiae(Psa))and Corynesporapolytica(Corynespora cassiicola).At present,the research on canker disease and brown spot disease mainly focuses on the isolation and identification of pathogenic bacteria,drug control,resistance gene mining and functional verification.Practice has proved that breeding disease resistant varieties are an effective method to control canker disease and brown spot disease.However,most existing cultivars lack genes for canker and brown spot resistance.Wild kiwifruit resources in nat-ure exhibit extensive genetic diversity due to prolonged natural selection,containing numerous resistance genes.But,due to insufficient understanding of the resistance of most kiwifruit varieties(lines)to canker disease and brown spot disease,some high-quality resources have not been fully utilized.The incidence of canker and brown spot of 18 kiwifruit cultivars(lines)was measured by inoculating isolated branches and leaves,and their resistance to canker and brown spot was analyzed according to the length,disease index,mean diameter,and systematic clustering.The results were as follows:Among 18 different kiwifruit varieties(lines)for canker disease,there were two highly resistant materials,eight disease-resistant materials,four disease-susceptible materials,and two highly susceptible materials.Moreover,regarding brown spot disease,there were one highly resistant material,five dis-ease-resistant materials,four susceptible materials,and three highly susceptible materials.Furthermore,four resources were resistant to both diseases.The outcomes provided a theoretical basis for breeding kiwifruit against canker and brown spot.

Study on Biological Characteristics of the Pathogen of Pistacia vera Leaf Brown Spot

[Objective] The paper was to study the occurrence rule of Pistacia vera leaf brown spot and the biological characteristics of its pathogen.[Method] The occurrence rule of P.vera leaf brown spot was investigated in field.A fungus was isolated and purified from the diseased tissue of P.vera,its cultural trait and morphological characteristics were observed in indoor experiment,and the classification status was identified according to its morphology.The effects of different temperatures on mycelial growth of the pathogen,as well as the effects of different temperatures and humidity on spore germination of the pathogen were also studied.[Result] P.vera leaf brown spot was a fungal disease,which mainly infected the leaves and fruits of P.vera,causing leaf spot and blight.The disease had serious incidence in introduction place of P.vera in China.The fungal disease was identified to be Alternaria alternaria,the appropriate temperature for mycelial growth was 20-25 ℃,the appropriate temperature for spore germination was 25-30 ℃,and the appropriate relative humidity was over 95%.[Conclusion] Late spring and early summer,as well as late summer and early autumn are two peak periods for incidence of the disease,continuous rain in summer is the decisive condition for the infection and outbreak of P.vera leaf brown spot.

Effects of Radix Curcumae Fungicides on Tobacco Brown Spot and Yield of Flue-cured Tobacco Leaves

This study aimed to investigate the effects of Radix Curcumae fungicides on tobacco brown spot and yield of flue-cured tobacco leaves. Through field experi- ments, control efficiency of Radix Curcumae fungicides against tobacco brown spot was investigated. The results showed that the average control efficiency of 400-fold, 600-fold and 800-fold Radix Curcumae fungicides against tobacco brown spot reached 37.83%, 34.09% and 24.32%, respectively. This study could provide the ba- sis for screening and application of plant-derived fungicides against tobacco brown spot.

Characterizing and Estimating Fungal Disease Severity of Rice Brown Spot with Hyperspectral Reflectance Data

Large-scale farming of agriculture crops requires real-time detection of disease for field pest management. Hyperspectral remote sensing data generally have high spectral resolution, which could be very useful for detecting disease stress in green vegetation at the leaf and canopy levels. In this study, hyperspectral reflectances of rice in the laboratory and field were measured to characterize the spectral regions and wavebands, which were the most sensitive to rice brown spot infected by Bipolaris oryzae （Helminthosporium oryzae Breda. de Hann）. Leaf reflectance increased at the ranges of 450 to 500 nm and 630 to 680 nm with the increasing percentage of infected leaf surface, and decreased at the ranges of 520 to 580 nm, 760 to 790 nm, 1550 to 1750 nm, and 2080 to 2350 nm with the increasing percentage of infected leaf surface respectively. The sensitivity analysis and derivative technique were used to select the sensitive wavebands for the detection of rice brown spot infected by B. oryzae. Ratios of rice leaf reflectance were evaluated as indicators of brown spot. R669/R746 （the reflectance at 669 nm divided by the reflectance at 746 nm, the following ratios may be deduced by analogy）, R702/R718, R692/R530, R692/R732, R535/R746, R521/R718, and R569/R718 increased significantly as the incidence of rice brown spot increased regardless of whether it＇s at the leaf or canopy level. R702/R718, R692/R530, R692/R732 were the best three ratios for estimating the disease severity of rice brown spot at the leaf and canopy levels. This result not only confirms the capability of hyperspectral remote sensing data in characterizing crop disease for precision pest management in the real world, but also testifies that the ratios of crop reflectance is a useful method to estimate crop disease severity.

Analysis of Meteorological Condition for Infection of the Pathogen of Tobacco Brown Spot (Alternaria alternate)

[Objective] The paper was to understand the suitable meteorological indexes and key meteorological factors for infection and prevalence of tobacco brown spot. [ Method] Tobacco brown spot disease in five topical mountainous climatic areas of Guizhou Province was investigated, and the difference of biological characteristics of different strains was analyzed indoor. Different meteorological conditions （light, temperature and humidity） were simulated in artificial climate box by using the uniform design method, and the difference of infection ability of Alternaria alternate in different climate zones was analyzed in leaves in vitro by hanging drop method. [ Result] The infection rate of A. alternate in different climate zones of Guizhou Province showed certain difference. In low temperature and mid- die humidity （the humidity is 50% -60%, the temperature is 10 -20 ℃） conditions, the pathogen could infect tobacco leaves, various strains had certain difference, but the difference was small. [ Conclusion] The paper provided theoretical basis for prevalence prediction and control of tobacco brown spot.

Comparative transcriptome profiling of two maize near-isogenic lines differing in the allelic state for bacterial brown spot disease resistance

The bacterial brown spot disease（BBS）, caused primarily by Pseudomonas syringae pv. syringae van Hall（Pss）, reduces plant vigor, yield and quality in maize. To reveal the nature of the defense mechanisms and identify genes involved in the effective host resistance, the dynamic changes of defense transcriptome triggered by the infection of Pss were investigated and compared between two maize near-isogenic lines（NILs）. We found that Pss infection resulted in a sophisticated transcriptional reprogramming of several biological processes and the resistant NIL employed much faster defense responses than the susceptible NIL. Numerous genes encoding essential components of plant basal resistance would be able to be activated in the susceptible NIL, such as PEN1, PEN2, PEN3, and EDR1, however, in a basic manner, such resistance might not be sufficient for suppressing Pss pathogenesis. In addition, the expressions of a large number of PTI-, ETI-, PR-, and WRKY-related genes were pronouncedly activated in the resistant NIL, suggesting that maize employ a multitude of defense pathways to defend Pss infection. Six R-gene homologs were identified to have significantly higher expression levels in the resistant NIL at early time point, indicating that a robust surveillance system（gene-to-gene model） might operate in maize during Pss attacks, and these homolog genes are likely to be potential candidate resistance genes involved in BBS disease resistance. Furthermore, a holistic group of novel pathogen-responsive genes were defined, providing the repertoire of candidate genes for further functional characterization and identification of their regulation patterns during pathogen infection.

Characterizing and estimating rice brown spot disease severity using stepwise regression,principal component regression and partial least-square regression

Detecting plant health conditions plays a key role in farm pest management and crop protection. In this study, measurement of hyperspectral leaf reflectance in rice crop (Oryzasativa L.) was conducted on groups of healthy and infected leaves by the fungus Bipolaris oryzae (Helminthosporium oryzae Breda. de Hann) through the wavelength range from 350 to 2 500 nm. The percentage of leaf surface lesions was estimated and defined as the disease severity. Statistical methods like multiple stepwise regression, principal component analysis and partial least-square regression were utilized to calculate and estimate the disease severity of rice brown spot at the leaf level. Our results revealed that multiple stepwise linear regressions could efficiently estimate disease severity with three wavebands in seven steps. The root mean square errors (RMSEs) for training (n=210) and testing (n=53) dataset were 6.5% and 5.8%, respectively. Principal component analysis showed that the first principal component could explain approximately 80% of the variance of the original hyperspectral reflectance. The regression model with the first two principal components predicted a disease severity with RMSEs of 16.3% and 13.9% for the training and testing dataset, respec-tively. Partial least-square regression with seven extracted factors could most effectively predict disease severity compared with other statistical methods with RMSEs of 4.1% and 2.0% for the training and testing dataset, respectively. Our research demon-strates that it is feasible to estimate the disease severity of rice brown spot using hyperspectral reflectance data at the leaf level.

云南省烟草赤星病(Tobacco brown spot)病原研究及其防治药剂的筛选

对云南省烟草赤星病 (Tobaccobrownspot) 1 2个代表菌株进行了培养性状、形态特征和致病力测定以及防治药剂筛选。结果表明 :它们属于长柄链格孢菌 (Aiternariaiongipes (EltetEV .)Fisdetwadk)和链格孢菌 (Aiternariaalternata(Fr.)keissl.) ,以后者居多。两者的菌落形态相似 ,温度反应一致 ;最低、最适、最高生长温度分别为 5℃ ,2 4℃ - 2 8℃和36℃。大多数链格孢菌的致病力比长柄链格孢菌致病力强。保鲜剂西奇爱是一种高效无毒无残留的理想防治药剂。

Characterization of the Rice Canopy Infested with Brown Spot Disease Using Field Hyperspectral Data

Based on the field hyperspectral data from the analytical spectral devices （ASD） spectrometer, we characterized the spectral properties of rice canopies infested with brown spot disease and selected spectral regions and bands sensitive to four severity degrees （severe, moderate, light, and healthy）. The results show that the curves＇ variation on the original and the first- and second-order de- rivative curves are greatly different, but the spectral difference in the near-infrared region is the most obvious for each level. Specifically, the peaks are located at 822, 738, and 793 nm, while the valleys are located at 402, 570, and 753 run, respectively. The sensitive regions are between 430-520, 530-550, and 650-710 nm, and the bands are 498, 539, and 673 nm in the sensitivity analysis, while they are in the ranges of 401-530, 550-730 as well as at 498 nm and 678 nm in the continuum removal.

苏铁羽叶褐斑病病原菌鉴定及其化学防治药剂的筛选

本研究旨在分离并鉴定造成苏铁属植物羽叶褐斑病的病原真菌,筛选出对该病原真菌具有强烈抑制作用的化学防治药剂,为苏铁的保护提供理论依据。首先,通过病斑组织分离、纯化后回接滇南苏铁叶片,根据科赫氏法完成其致病性验证。其次,对其进行形态鉴定;再应用SSU、LSU、GAPDH、tef1、rpb2、Alt、OPA10-2、ITS 8个基因序列,构建多基因进化树进一步鉴定病原真菌。最后,通过平板抑菌试验,从7种化学药剂中筛选出高效的抗菌药剂。本研究发现,形态学鉴定与多基因联合进化分析表明,该病原菌为链格孢属的巴斯基链格孢(Alternariaburnsii);在7种化学药剂平板抑菌试验中,氟酰羟·苯甲唑效果最佳,其浓度在0.67 mg/L时抑菌率达到73.48%。

Loss Rate Estimation of Yield and Output Value of Tobacco Leaf Infected by Tobacco Blown Spot (Alternaria alternata)

[Objective] The paper was to study the effect of tobacco blown spot on the yield and output value of tobacco leaf.[Method]The upper,middle and lower leaves in tobacco plant were selected during the harvest period of tobacco to carry out loss rate estimation of yield and output value of tobacco leaf caused by different disease levels of brown spot.Regression correlation analysis was also conducted.[Result]The disease levels of brown spot had extremely significant strong negative correlation with single leaf weight of tobacco leaf,and it had extremely significant strong positive correlation with the loss rate of single leaf weight.The increase speed of loss rate of single leaf weight of middle and upper leaves was obviously faster than that of lower leaves.The loss rates of single leaf weight of upper,middle and lower leaves were 3.18%-28.95%,3.43%-28.88% and 10.07%-26.90%,respectively.The higher the disease level of blown spot was,the lower the yield and output value of tobacco leaf was,and the corresponding loss rate was also higher.Correlation analysis showed that the disease level of blown spot had extremely significant strong negative correlation with the yield and output value of tobacco leaf,and it had extremely significant strong positive correlation with the loss rate of yield and output value.The negative impact of blown spot on the output value of tobacco leaf was far greater than that on the yield.The highest loss rate of the yield of tobacco leaf was 28.56%,while the highest loss rate of output value reached 89.67%.[Conclusion] The study provided theoretical basis for accurately holding the critical period for the control of blown spot,thus reducing the damage on tobacco leaf and improving the output value of tobacco leaf.

龙牙百合褐斑病病原的鉴定、生物学特性及室内药剂筛选

为明确龙牙百合褐斑病病原,采集龙牙百合褐斑病典型症状的叶片,进行病原物分离、纯化和致病性测定,结合病原菌形态学观察及其rDNA-ITS、gapdh、tef1、RPB2和Alt a1等基因的序列分析,确定引起龙牙百合褐斑病的病原菌为枝状链格孢Alternaria arborescens。采用菌丝生长速率法,测定了光照、温度、pH值、碳源、氮源和不同培养基等处理对该病原菌生长的影响,并测定了病原菌对7种杀菌剂的敏感性。结果表明,最适合菌丝生长的条件为温度25℃,pH值5.0,碳源为蔗糖,氮源为牛肉浸膏,培养基为马铃薯葡萄糖琼脂(PDA)培养基;菌落致死温度为50℃。在7种参试药剂中,木霉菌抑制作用最强,其半数效应浓度(EC_(50))和90%效应浓度(EC_(90))值最低,分别是8.758×10^(-5)和0.198 mg·L^(-1);噁唑菌酮代森锰锌的毒力最低,EC_(50)和EC_(90)值分别为13.713和816.937 mg·L^(-1)。本研究结果为龙牙百合褐斑病菌的精准防控提供了理论依据。

新疆大果沙枣果实褐斑病菌主要生物学特性及室内药剂筛选

明确沙枣果实褐斑病菌(Alternaria alternata)的主要生物学特征并室内筛选防治药剂,可为沙枣果实褐斑病的科学研究和化学防控奠定一定的理论基础。采用菌丝生长速率法,通过测定新疆大果沙枣果实褐斑病病菌在不同碳源种类、温度、pH值和光照条件下的生长速率,初步明确该病原菌的主要生物学特性;通过室内毒力试验,根据毒力回归方程求得的各杀菌剂抑菌中浓度(EC50),筛选对病原菌具有较强抑菌效果的药剂。结果表明:除光照条件外,其他3种因素均对病原菌丝生长具有显著影响,其中最适培养基为以葡萄糖为碳源的PDA培养基,最适生长温度为(26±1)℃,最适pH值为7左右,最适光照条件为24 h全光照;不同药剂对大果沙枣果实褐斑病原菌的毒力存在明显差异,其中,25%吡唑嘧菌酯(23.099 mg/L)、43%戊唑醇(24.060 mg/L)、40%氟硅唑(36.454 mg/L)和80%代森锰锌的EC50(97.207 mg/L)均低于100 mg/L,对病原菌具有较强毒力。对沙枣果实褐斑病菌主要生物学特性的研究明确了该菌的最佳生长环境,为后期的进一步研究提供了技术支持。室内筛选的4种杀菌剂可以作为田间防治试验的备选药剂。

烟草赤星病拮抗菌YZ01发酵条件优化及抑菌活性物质初探

由链格孢菌Alternariaalternata引起的赤星病是烟草上的主要叶部病害之一,常常造成巨大的经济损失。对烟草赤星病菌具有显著拮抗活性的菌株YZ01进行鉴定、活性物质探究及发酵条件优化,可为烟草赤星病的防治提供菌种资源,为指导其实际生产应用奠定基础。通过形态学、生理生化特征及16S rRNA和gyrA基因序列系统发育分析,鉴定菌株YZ01为贝莱斯芽胞杆菌Bacillusvelezensis。无菌滤液抑菌试验发现贝莱斯芽胞杆菌YZ0110%无菌滤液对烟草赤星病菌Alternariaalternata的抑菌率为86.56%,对苹果腐烂病菌Valsa mali、辣椒疫霉病菌Phytophthora capsici、番茄灰霉病菌Botrytis cinerea、苹果炭疽叶枯病菌Colletotrichum fructicola的抑菌率为100.00%。进一步研究发现,贝莱斯芽胞杆菌YZ01发酵液可使烟草赤星病菌菌丝细胞结构受损,导致其原生质体外渗,从而抑制菌丝生长,其发酵液抑菌活性成分主要为脂肽及蛋白类物质。单因素试验法和正交实验优化菌株YZ01的最佳发酵培养基配方为葡萄糖0.50%、胰蛋白胨1.50%和磷酸氢二钾1.50%。发酵液稳定性测定发现,其抑菌活性受温度、pH和紫外处理的影响较小。综上所述,该结果为烟草赤星病的生物防治提供了菌种资源,也为后续田间应用奠定了基础。

氟唑菌酰羟胺对烟草赤星病的防效及对烟叶和土壤的安全性

为明确烟草赤星病菌对新型杀菌剂氟唑菌酰羟胺的敏感性水平以及该药在烟叶和土壤中的安全性,采用菌丝生长速率法和孢子萌发法测定了烟草赤星病菌对氟唑菌酰羟胺的敏感性,并在云南、四川、贵州、福建、重庆等省市开展了田间防效试验,分析了其在烟叶上的残留降解,同时采用高通量测序分析了其对土壤细菌和真菌群落结构和共发生网络的影响。结果表明,烟草赤星病菌在不同发育阶段对氟唑菌酰羟胺敏感性差异较大,其中菌丝生长阶段最为敏感,对169株病株的EC50值为0.0064~0.1832 mg/L。氟唑菌酰羟胺2次施药对烟草赤星病的田间防效达到69.42%~88.09%,并增加了烟叶产量。另外,氟唑菌酰羟胺在鲜烟叶和干烟叶的降解半衰期范围为3.2~8.8 d。氟唑菌酰羟胺使用后土壤中链霉菌属、假单胞菌属、木霉菌属、拟青霉属等有益菌显著富集,且细菌和真菌共发生网络的复杂度增加。因此,氟唑菌酰羟胺可用于烟草赤星病的防治。

桑褐斑病病原菌的分离鉴定及高通量测序分析

桑褐斑病是一种发生较为普遍的真菌性病害。从陕西安康蚕桑主产区收集桑褐斑病病样,结合科赫氏法则,采用形态学及分子生物学的方法对桑褐斑病病原菌进行分离鉴定;使用高通量测序技术,确定桑褐斑病病原菌的主要类群;通过水合氯醛透明反应观察桑褐斑病病原菌在宿主桑树叶片中的定植状态。结果表明,侵染陕西安康桑树的桑褐斑病病原菌为桑新褐斑壳丰孢Neophloeospora maculans;病原菌在PDA培养基上呈白色,生长速度缓慢,分生孢子为透明圆柱形,两端逐渐变细,有隔膜;菌丝主要寄生在桑叶的气孔与叶脉周边;病原菌rDNA序列全长5512 bp,GC含量51.16%。上述结果确定了侵染陕西安康蚕桑主产区桑褐斑病病原菌的种类,为桑褐斑病的防治提供了理论依据。

鳄梨采前果实黑褐色病斑病原鉴定及田间药剂防治

为明确位于广东省湛江市的中国热带农业科学院南亚热带作物研究所种质资源圃采前油梨果实表皮黑褐色病斑病原菌,采用组织分离法从病果上分离病原菌,采用形态学结合分子生物学方法鉴定病原菌,选取代表菌株进行油梨果实、叶片、茎干等部位致病性测定,并进行40%多菌灵悬浮液和25%嘧菌酯悬浮液对该病害的田间防治试验。结果表明,从15个油梨病果分离获得病原菌36株,根据形态学观察结合分子鉴定,将36株病原菌划分为刺盘孢属(Colletotrichum)的两个种,对两个种的代表菌株YLQ5-2和FNYG1进行多基因(ITS、GAPDH、CAL、TUB和ACT)系统发育分析,菌株YLQ5-2和菌株FNYG1分别与暹罗刺盘孢(Colletotrichum siamense)和果生刺盘孢(C.fructicola)聚为一支。致病性测定发现,刺伤状态下可引起油梨果实产生黑斑,无伤条件下即可导致油梨叶部发病,刺伤也无法使油梨茎干发病,表现出致病组织特异性。在油梨果实膨大期(7—9月)连续喷施25%嘧菌酯悬浮剂1500倍液和40%多菌灵悬浮剂500倍液3次防治该病害,防效均超过50%以上,其中,25%嘧菌酯的防效较高,达到87.1%。

烟草赤星病拮抗菌群发酵条件优化及可湿性粉剂研制

为获得防治烟草赤星病高效生防菌剂,采用单因素试验和正交试验设计优化烟草赤星病拮抗菌群发酵工艺,筛选载体、助剂制备可湿性粉剂,并验证其田间应用效果。结果表明,最适发酵培养基为葡萄糖10 g/L、胰蛋白胨2.5 g/L、酵母粉2.5 g/L、NaCl 10 g/L;最佳发酵条件为pH 8.0、发酵温度35℃、接种量7%、装液量125 mL/250 mL;可湿性粉剂最佳配方为载体白炭黑(15%)、分散剂木质素磺酸钠(1%)、润湿剂吐温80(10%)、稳定剂K2HPO4(2%)、保护剂羧甲基纤维素(0.1%)。田间小区处理7和14d后,可湿性粉剂对烟草赤星病的防效分别为51.58%和52.81%,生防应用前景良好。

江西省猕猴桃褐斑病发生情况、病原鉴定与高效药剂筛选

【目的】明确江西省猕猴桃褐斑病发生情况及其病原,筛选能有效抑制病原的杀菌剂,为猕猴桃褐斑病防控提供新的依据。【方法】以猕猴桃褐斑病为研究对象,调查江西省猕猴桃褐斑病发生情况。对褐斑病主要流行区的病叶进行病原分离,通过科赫氏法则验证、形态观察和分子鉴定确定病原。采用菌丝生长速率法对9种药剂进行室内毒力测定。【结果】猕猴桃褐斑病在赣西和赣北发生严重,11个调查点位中5个点位发病等级中值在5级及以上;猕猴桃褐斑病在赣东和赣南发生较轻,10个调查点位的发病等级中值均为0。通过科赫氏法则验证、形态观察和分子鉴定,确定病原为多主棒孢(Corynespora cassiicola)。室内药剂毒力测定结果表明,丙硫菌唑、环丙唑醇、克菌丹和腈菌唑对猕猴桃褐斑病菌具有极强的抑制作用,EC_(50)分别为17.36,6.97,5.30和2.50μg·mL^(-1)。【结论】猕猴桃褐斑病在赣北和赣西发生严重,病原鉴定为多主棒孢;丙硫菌唑、环丙唑醇、克菌丹和腈菌唑可作为猕猴桃褐斑病防治的潜在高效药剂。