Amount Of Fungicide Research Articles

Automatic Classification of Cotton Root Rot Disease Based on UAV Remote Sensing

Cotton root rot (CRR) is a persistent soilborne fungal disease that is devastating to cotton in the southwestern U.S. and Mexico. Research has shown that CRR can be prevented or at least mitigated by applying a fungicide at planting, but the fungicide should be applied precisely to minimize the quantity of product used and the treatment cost. The CRR-infested areas within a field are consistent from year to year, so it is possible to apply the fungicide only at locations where CRR is manifest, thus minimizing the amount of fungicide applied across the field. Previous studies have shown that remote sensing (RS) from manned aircraft is an effective means of delineating CRR-infested field areas. Applying various classification methods to moderate-resolution (1.0 m/pixel) RS images has recently become the conventional way to delineate CRR-infested areas. In this research, an unmanned aerial vehicle (UAV) was used to collect high-resolution remote sensing (RS) images in three Texas fields known to be infested with CRR. Supervised, unsupervised, and combined unsupervised classification methods were evaluated for differentiating CRR from healthy zones of cotton plants. Two new automated classification methods that take advantage of the high resolution inherent in UAV RS images were also evaluated. The results indicated that the new automated methods were up to 8.89% better than conventional classification methods in overall accuracy. One of these new methods, an automated method combining k-means segmentation and morphological opening and closing, provided the best results, with overall accuracy of 88.5% and the lowest errors of omission (11.44%) and commission (16.13%) of all methods considered.

Status of copper accumulation in agricultural soils across China (1985-2016).

The first national-scale assessment of Cu contamination of agricultural soils covering 1731 sites in China was performed based on 1837 published papers. The temporal and spatial variations from 1985 to 2016 in the Cu concentrations and the ecological and health risks associated with Cu exposure were analyzed. Approximately, 21.02% of the sampling sites revealed Cu concentrations that exceeded the screening value (50.00mg/kg; GB15618-2018). The Cu concentrations differed among five geographical regions in the decreasing order of South China>West China>East China>Northeast China>North China. Notably, concentration of Cu in agricultural soils have begun to diminish since 2011 due to reduced heavy metal inputs. Cu mainly originated from anthropogenic activities such as mining and agricultural activities. Linear correlations were observed between the amounts of fungicides and fertilizers applied and the Cu concentrations in the soils, which suggested that the application of fungicides and fertilizers is an important contributor to the accumulation of Cu in soils. Additionally, the geoaccumulation index (Igeo) and ecological risk index (Efi) values implied that pollution and ecological risk resulting from soil Cu concentration were in low levels. The hazard index (HI) values were higher for children than for adults. Therefore, children should be prioritized for protection from heavy metal pollution. Overall, this study details the status of Cu contamination of agricultural soils in China, and thus provides insights for policymakers regarding the preventive measures.

Dissipation of chlorothalonil in the presence of chlortetracycline and ciprofloxacin and their combined effects on soil enzyme activity.

The long-term application of substantial amounts of fungicides and antibiotic-polluted organic manure (OM) in greenhouse has caused the co-existence of fungicides and antibiotics in soils. However, little is known about the effects of antibiotics on the persistence of fungicides in soils or their combined effects on soil enzyme activity. In this study, fungicide chlorothalonil (CTL) alone and in combination with antibiotic chlortetracycline (CTC) or ciprofloxacin (CIP) were repeatedly added to OM-amended soil to investigate the changes in the residual characteristics of CTL and in soil dehydrogenase and urease activity. The results showed that CTL rapidly dissipated in soils with the corresponding half-lives of 0.9-3.2, which initially increased, then decreased and finally stabilized with an increased treatment frequency. The dissipation of CTL was inhibited by CTC and CIP during the first several treatments. The soil dehydrogenase and urease activity in CTL-treated soils was inhibited during the first six treatments and then recovered afterwards. Compared with the OM-amended soil+CTL treatment, the OM-amended soil+CTL+CTC and OM-amended soil+CTL+CIP treatments had stronger inhibitory effects on soil enzyme activity during the first six repeated treatments but exhibited slight stimulating effects afterwards. Therefore, the results obtained in this study suggested that the long-term co-existence of CTL, CTC, and CIP altered the dissipation characteristics of CTL in soil and affected the soil enzyme activity levels. The prudent application of large and frequent of fungicides and OM-containing antibiotic residues in greenhouses should therefore be carefully considered in order to reduce the long-term combined pollution in soils.

What about the environment?

PurposeFungus-resistant grape varieties (FRGVs) are the key to more environment-friendly wine growing. This paper aims to examine whether German consumers are willing to buy environment-friendly wines. The study focuses on reducing the amount of fungicides applied and the improvement of the carbon footprint, which are both related to the FRGVs . Furthermore, a cluster analysis leads to more insights into the consumer groups that are open to environment-friendly wine.Design/methodology/approachA choice experiment was conducted among 1,500 German wine drinkers with the following attributes: “reduction of pesticides”, “reduction of carbon emissions”,“familiarity with the grape variety”,“organic certification”, the slogan “better for the environment” and“price”. The individual-level, part-worth utilities were estimated using the Hierarchical Bayes method. The Ward’s method was used to cluster the individual-level, part-worth utilities. The participants’ wine involvement and environmentalism are used to further analyse the sample.FindingsThe most important attribute is “price”, followed by the “familiarity with the grape variety” and the “reduction of pesticides” and of “carbon emissions”. The least important attribute is “better for the environment”. The cluster analysis results in three clusters: the green-minded, the traditionalists and the price-minded.Practical implicationsThe insights about the consumer acceptance of environment-friendly wines can be used to market these wines more effectively to consumers.Originality/valueThis is the first study that combines a choice experiment with attributes that are derived from the benefits of fungus-resistant grape varieties.

Synergistic effect of plant extracts and fungicide against purple blotch disease of onion

Onion is widely cultivated crop and attacked by different fungi. Purple blotch of onion caused by Alternaria porri is a continuous threat to Pakistan agriculture industry for the last few years. Generally, fungicides give satisfactory control but due to the environmental concerns, their use should be restricted. In integrated disease management program, cost effective and eco-friendly approach is used to cope with plant pathogens. Therefore, the present study was planned to evaluate the antifungal efficacy of different plants extracts such as Pongamia pinnata, Polyalthia longifolia, Cassia fistula, and Citrus sinensis against A. porri alone as well as synergistically with different concentrations of Mancozeb under in vitro conditions. Methanolic leaves extracts of these plants were mixed with different concentrations (25, 50, and 75%) of fungicide and screened via poisoned food technique to measure percent inhibition of fungal growth. The results indicated that plant extracts alone gave appreciable amount of fungal reduction but when used in combination with fungicide, performed best. Among them P. longifolia gave 73%inhibition, C. sinensis 49%, P. pinnata 70%and Cassia fistula showed46% inhibition respectively. In combination with fungicide, 25% of recommended dose, P. longifolia gave 82.93%, P. pinnata gave 77.07 %, C. sinensis 73.17% and C. fistula gave 62.92% inhibition as compared to control against A. porri. With the increase of fungicide in combination, more reduction in the fungal growth was observed. It is concluded that extracts can be used synergistically with fungicides. The combinations will protect the environment by reducing the amount of fungicide

Influence of chlorothalonil and carbendazim fungicides on the transformation processes of urea nitrogen and related microbial populations in soil.

To improve crop yielding, a large amount of fungicides is continuously applied during the agricultural management, while the effects of fungicides residues on microbial processing of N in soil need further study. In the present study, two broad spectrum fungicides, chlorothalonil and carbendazim, were applied at the rates of 5, 10, and 50 mg of active ingredient (A.I.) per kg of dry soil combined with urea with 200 mg of N per kg of dry soil under laboratory conditions. The results showed that chlorothalonil obviously retarded the hydrolysis of urea, whereas carbendazim accelerated it in 4 days after the treatments (P < 0.05). Chlorothalonil reduced denitrification, nitrification, and N2O production (P < 0.05), but not for carbendazim. Further analysis on N-associated microbial communities showed chlorothalonil reduced nitrosomonas populations at the rates of 10 and 50 mg of A.I. per kg and autotrophic nitrifying bacterial populations at three application rates (P < 0.05), but Carbendazim decreased nitrosomonas populations only at the rate of 50 mg of A.I. per kg and also autotrophic nitrifying bacterial populations at three rates and heterotrophic nitrifying bacterial populations at the rates of 10 and 50 mg of A.I. per kg. The reasons for this difference were ascribed to arrest urea hydrolysis and impediment of denitrification and nitrification processes by chlorothalonil. In conclusion, to improve crop yielding, chlorothalonil might be more beneficial to conserve soil N by improving soil N fertility, compared with carbendazim.

ANTIFUNGAL EFFICIENCY OF COPPER OXYCHLORIDE-CONJUGATED SILVER NANOPARTICLES AGAINST COLLETOTRICHUM GLOEOSPORIOIDES WHICH CAUSES ANTHRACNOSE DISEASE

Objectives: Anthracnose disease is caused by Colletotrichum gloeosporioides, affecting most of the fruit and vegetable plants. The present study is aimed to synthesize silver nanoparticles (AgNPs) using neem extract and conjugate then with fungicide to check the antifungal activity against anthracnose disease.&#x0D; Methods: In the current study, we have synthesized copper oxychloride-conjugated AgNPs (COC-AgNPs) by a biological method using neem extract and have tested their effectiveness against C. gloeosporioides. The COC-AgNPs were characterized by UV–visible spectroscopy, fourier-transform infrared, scanning electron microscopy, and X-ray diffraction analysis, and in vitro antifungal activity was investigated.&#x0D; Results: The shape of COC-AgNPs was found to be spherical with an average particle size of 21–25 nm. The fungicide-conjugated AgNPs exhibited highest growth inhibition of C. gloeosporioides (~187%) as compared to fungicide copper oxychloride.&#x0D; Conclusion: These results indicate that the COC-AgNPs could be effectively used to control anthracnose disease in mango and in other crops. These COC-AgNPs can drastically reduce the amount of fungicide currently used which will reduce the environmental pollution caused by the fungicide.

Targeted Drug Delivery in Plants: Enzyme-Responsive Lignin Nanocarriers for the Curative Treatment of the Worldwide Grapevine Trunk Disease Esca.

Nanocarrier (NC)‐mediated drug delivery is widely researched in medicine but to date has not been used in agriculture. The first curative NC‐based treatment of the worldwide occurring grapevine trunk disease Esca, with more than 2 billion infected plants causing a loss yearly of $1.5 billion, is presented. To date, only repetitive spraying of fungicides is used to reduce chances of infection. This long‐term treatment against Esca uses minimal amounts of fungicide encapsulated in biobased and biodegradable lignin NCs. A single trunk injection of <10 mg fungicide results in curing of an infected plant. Only upon Esca infection, ligninolytic enzymes, secreted by the Esca‐associated fungi, degrade the lignin NC to release the fungicide. The specific antifungal activity is confirmed in vitro and in planta (in Vitis vinifera L. cv. ‘Portugieser’). All treated plants prove to exhibit significantly fewer symptoms several weeks after treatment, and their condition is monitored for 5 years (2014–2018), proving a long‐term curative effect of this NC treatment. This study proves the efficacy of this NC‐mediated drug delivery for agriculture, using a minimum amount of fungicides. It is believed that this concept can be extended to other plant diseases worldwide to reduce extensive spraying of agrochemicals.

Transcriptome analysis of early downy mildew (Plasmopara viticola) defense in grapevines carrying the Asian resistance locus Rpv10

The oomycete Plasmopara viticola (Berk. & Curt.) Berl. & de Toni causes downy mildew, one of the most devastating diseases of grapevine (Vitis vinifera L.). Traditional European grapevine cultivars are highly susceptible to this obligate biotrophic pathogen. Large amounts of fungicides are necessary to protect the grapevine plants and secure harvest. This strong requirement for protective chemicals conflicts with the modern demand for sustainability in agriculture. A significant reduction of chemical protection is possible by generating novel robust grapevine cultivars through resistance breeding. Current grapevine breeding utilizes marker-assisted genetic selection. The aim is to combine diverse resistance loci for durable resistance. Markers tagging various resistance loci were elaborated during the last 10 years. However, knowledge about the conveyed defense mechanisms is still sparse but would be essential to optimize the combination of resistance loci. Asian Vitis amurensis accessions carry resistance against downy mildew e.g. in the Rpv10 locus. This locus has been introgressed into the resistant grapevine cultivar ‘Solaris’ and was genetically mapped to chromosome nine. To understand its mode of action in early defense reactions we performed a comparative RNA sequencing analysis after pathogen challenge of Rpv10-carriers, Rpv10-carriers containing additionally the resistance locus Rpv3 from American Vitis sp. origin and non-Rpv carriers. This study indicated comprehensive transcriptional re-programming and a large number of differentially expressed genes. The data indicates that the difference between resistant and susceptible grapevines relies in the increased amount of responsive genes and the efficiency of early signal transduction. This results in the fast activation of large gene clusters encoding phenylalanine ammonium lyase and stilbene synthase on chromosome 16.

A Cloud-IOT Based Decision Support System for Potato Pest Prevention

Adopting decision support system (DSS) in farming to prevent potato late blight disease has proven its utility. As a matter of fact, the DSS grants efficiency, and reduces production cost as well as the impact on the environment as that it estimates the exact amount of fungicide that must be applied. This estimation uses environmental condition-based blight forecast model. Usually requires weather information collected from costly weather stations or imprecise historical data. However, climate data could be collected easily thanks to the evolution of the Internet of Things (IOT). In fact, this could be done by deploying a large number of low-cost, low-power sensor nodes inside farms. Climate data can be routed afterwards from the sensors to the Cloud-IOT framework through an internet connection. In this paper, we developed and experimented Cloud-IOT based late blight decision support system. In comparison with to the state of art DSS, report our proposed system offers wider accessibility and a cheaper cost.

Pathogenicity Traits Correlate With the Susceptible Vitis vinifera Leaf Physiology Transition in the Biotroph Fungus Erysiphe necator: An Adaptation to Plant Ontogenic Resistance.

How and when the pathogen cycle is disrupted during plant development is crucial for harnessing ontogenic resistance in sustainable agriculture. Ontogenic resistance against powdery mildew (Erysiphe necator) was quantified on Vitis vinifera. Shoots were sampled in the vineyard at several dates during seasonal growth and processed in the laboratory under controlled conditions. Experiments were conducted on two susceptible Vitis vinifera Cabernet Sauvignon and Merlot. The process of leaf ontogenic resistance was investigated by measuring three quantitative traits of pathogenicity: the infection efficiency, sporulation and mycelium growth. Morphological and physiological plant indicators were used to identify leaf changes that resulted in ontogenic resistance and to predict pathogen variations that were linked to pathogenicity traits. The process of ontogenic resistance was established early in correspondence with the physiological transition of the leaf from sink to source status and was characterized by its increase in sugar content. The three traits of pathogenicity that we measured were affected, and their variation was strongly correlated with leaf age. Using leaf age, we were able to accurately predict the susceptibility of the leaf: a leaf aged, on average, 13.3 days had a very high probability (0.8) of being susceptible, while this probability decreased to 0.5 one week later. Sporulation was more closely correlated with variations in sugar and the infection efficiency in leaf water. The results for both cultivars were consistent. Ontogenic resistance on grapevine leaves is thus interpreted to be a strong, immutable physiological process that E. necator is able to circumvent by restricting its development to sink tissue. Future research should explore how this native plant resistance can be incorporated into grape management strategies to better control powdery mildew (PM) epidemics with reduced amounts of fungicides.

Leaf area, spray volumes and applicable quantities of fungicide during the protection period for control of Asian soybean rust

ABSTRACT The purpose of this study was to check the influence of leaf area index, spray volumes and applicable quantities of fungicide during the protection period, and for control of Asian soybean rust. All tests were conducted in the field and in the laboratory between 2014 and 2016. The quantity of fungicide and the spray volume were varied in the application of fungicides on soybean plants with different leaf area index. Rainfall simulation tests were also carried out at different times after application of fungicide. The spray volume and application rate of fungicide should be adequately proportioned according to the leaf area index of the soybean cultivar. The closer to the time of application that the rain occurs, the lower the control obtained by applying the fungicide. The leaf area index, the fungicide application rates, and the spray volumes influenced the protection period of fungicides and the control of Asian soybean rust.

Oligosaccharides successfully thwart hijacking of the salicylic acid pathway by Phytophthora infestans in potato leaves

Potato growing is severely threatened by the late blight agent Phytophthora infestans, which is usually controlled by massive amounts of fungicides. While variety resistance is often bypassed by the pathogen, the plant innate immunity opens the way to new biological plant protection tools, e.g. the COS‐OGA elicitor. This oligosaccharide composition mimics the interaction between plants and fungal pathogens as it combines chitosan oligomers (COS) with pectin‐derived oligogalacturonides (OGA). Two different COS‐OGA elicitors were evaluated against potato late blight: FytoSave, mainly efficient against powdery mildews, and FytoSol, a new composition still under development. In addition, a comparative study of plant defence induction was performed, focusing on the effect of repeated sprayings as well as on the stimulation of salicylic acid (SA), jasmonic acid and ethylene‐related pathways during the biotrophic and necrotrophic growth stages of the pathogen. The FytoSave elicitor strongly increased the SA content but failed to induce sufficient protection against late blight, while FytoSol maintained or even decreased the free SA content in the presence of P. infestans and was completely efficient. Surprisingly, the necrotrophic development of P. infestans occurred along with a strong leaf accumulation of free SA and SA‐related transcripts. This may represent an attempt by P. infestans to divert plant defences for its own benefit. Preventive sprayings with FytoSol but not FytoSave completely impeded this hijacking. FytoSol seemed to keep the SA pathway under control, thereby preventing its diversion by P. infestans.

Frequency of a natural truncated allele of MdMLO19 in the germplasm of Malus domestica

Podosphaera leucotricha is the causal agent of powdery mildew (PM) in apple. To reduce the amount of fungicides required to control this pathogen, the development of resistant apple cultivars should become a priority. Resistance to PM was achieved in various crops by knocking out specific members of the MLO gene family that are responsible for PM susceptibility (S-genes). In apple, the knockdown of MdMLO19 resulted in PM resistance. However, since gene silencing technologies such as RNAi are perceived unfavorably in Europe, a different approach that exploits this type of resistance is needed. This work evaluates the presence of non-functional naturally occurring alleles of MdMLO19 in apple germplasm. The screening of the re-sequencing data of 63 apple individuals led to the identification of 627 single nucleotide polymorphisms (SNPs) in five MLO genes (MdMLO5, MdMLO7, MdMLO11, MdMLO18, and MdMLO19), 127 of which were located in exons. The T-1201 insertion of a single nucleotide in MdMLO19 caused the formation of an early stop codon, resulting in a truncated protein lacking 185 amino acids, including the calmodulin-binding domain. The presence of the insertion was evaluated in 115 individuals. It was heterozygous in 64 and homozygous in 25. Twelve of the 25 individuals carrying the insertion in homozygosity were susceptible to PM. After barley, pea, cucumber, and tomato, apple would be the fifth species for which a natural non-functional mlo allele has been found.

TENACITY AND PERSISTENCE OF COPPER FUNGICIDES IN CITRUS SEEDLINGS UNDER SIMULATED RAINFALL

ABSTRACT The amount of fungicide that adheres to the leaf during spraying and the amount that remain on the leaf after weathering are the main factors that defines the amount of active residue on the leaf surface to effectively control plant pathogens. Thus, the objective of this work was to evaluate the tenacity and persistence of copper in citrus seedling leaves under simulated rainfall in Jaboticabal, State of São Paulo, Brazil. The evaluated variables were copper content, solution retention, surface tension and drop spectrum. A significant and inversely proportional linear relationship to drops &lt;100 µm was found. The percentage of copper retained in leaves of citrus seedlings with copper fungicides of suspension concentrate (SC) formulations after simulated rainfall was greater than 80%. Copper fungicides of SC formulations presented the lowest surface tension, allowing greater tenacity and persistence of copper on seedlings of citrus leaves after simulated rainfall and increased contact between the drops and leaf surface.

Mitigation of fungicide pollution in detention ponds and vegetated ditches within a vine-growing area in Germany

Large amounts of fungicides are commonly applied to agricultural fields, particularly vineyards. Following their application, fungicides may accidentally be introduced into agricultural surface waters posing a potential risk for the integrity of aquatic ecosystems. In this context, the present study characterized the aquatic fungicide exposure at base flow and during rainfall-related runoff events in viticulture in Southern Palatinate (SW-Germany) between 2006 and 2009. The mitigation performance of three vegetated ditches (VD) and five vegetated detention ponds (DP) was assessed. The measurements uncovered the presence of 4 to 11 different fungicide compounds in each of the 81 samples. During runoff events, the ecotoxicological potential – expressed as the sum of toxic units calculated based on the acute toxicity towards algae, Daphnia and fish – of some of the mixtures detected at the inlet of the VD or DP exceeded the Uniform Principle threshold set by the European Union. Both the VD and the DP systems reduced the median fungicide concentrations and thus their associated ecotoxicological potential by 56% and 38%, respectively. This fungicide mitigation efficiency was mainly explained by the plant density and size-related properties of the vegetated systems. Although VP and DP are promising tools to mitigate fungicide exposure, a better mechanistic understanding of the factors triggering the remediation potential finally feeding back into policy decision making is required.

Caracterización Fenotípica de Mycosphaerella fijiensis y su Relación con la Sensibilidad a Fungicidas en Colombia

El control de &lt;em&gt;Micosphaerella fijiensis,&lt;/em&gt; requiere cada vez la aplicación de una mayor cantidad de fungicidas debido a la resistencia que este patógeno ha desarrollado. Se realizó una caracterización fenotípica de aislamientos de &lt;em&gt;M. fijiensis&lt;/em&gt; en relación a su sensibilidad a los fungicidas piraclostrobin, epoxiconazol y tridemorf esperando complementar los métodos actuales de monitoreo de resistencia. A partir de tejido foliar sintomático recolectado desde 12 fincas bananeras de Colombia durante los años 2013 y 2014, se obtuvo aislamientos monospóricos a los que se les cuantificó la sensibilidad poblacional e individual. Posteriormente esta sensibilidad se comparó con los rasgos fenotípicos que cada aislamiento expresó. Los resultados indicaron que los rasgos asociados con una mayor sensibilidad a piraclostrobin se expresaron en un mayor número de individuos, además se observó la expresión de estos mismos rasgos como respuesta a epoxiconazol. Para tridemorf se observó un aparente dominio compartido entre individuos con rasgos asociados a baja y alta sensibilidad. Una caracterización fenotípica permitiría conocer si existe un mayor o menor número de individuos tolerantes a un ingrediente activo y poder definir de esta forma el momento adecuado para aplicar este ingrediente activo sin aumentar la presión de selección sobre estos individuos.

Effects of fungicides on decomposer communities and litter decomposition in vineyard streams

Large amounts of fungicides are applied globally and partly enter freshwater ecosystems. A few laboratory studies examined their effects on decomposer communities and the ecosystem process of litter decomposition (LD), whereas the field situation remains largely unknown. We conducted a field study with 17 stream sites in a German vineyard area where fungicides represent the dominant pest control agent. Passive samplers were used to monitor 15 fungicides and 4 insecticides in streams and their toxicity was described using the toxic unit approach, whereas sediment samples were taken to characterise total copper concentrations. Microbial and leaf-shredding invertebrate community composition and related LD rates were assessed at each site. The structure of microbial and shredder communities as well as fungal biomass changed along the fungicide toxicity gradient. The changes in microbial endpoints were associated with a reduction of microbial LD rate of up to 40% in polluted streams. By contrast, neither the invertebrate LD rate nor in-situ measured gammarid feeding rates correlated with fungicide toxicity, but both were negatively associated with sediment copper concentrations. A subsequent laboratory experiment employing field fungicide concentrations suggested that the microbial community changes are causal. Overall, our results suggest that fungicides can affect LD under field conditions.

A STOCHASTIC FRONTIER ANALYSIS TO EXAMINE RESEARCH PRIORITIES FOR GENETICALLY ENGINEERED PEANUTS

AbstractPesticide applications are essential for peanut production to control insects, weeds, and other plant pathogens and for a profitable operation. We use a stochastic frontier analysis/primal system approach to test the hypothesis of the overuse of fungicides among peanut farmers. With nationally representative data available from the Agricultural and Resource Management Survey, we find evidence that U.S. peanut growers used excessive amounts of fungicides to prevent fungal infections. If those farmers adopt a new cultivar resistant to fungal pathogens, they could reduce the total cost of chemicals up to 36.2%. The reduction in fungicide use would have spillover environmental benefits.

Early Visualization Detection of Gray Mold (&lt;i&gt;Botrytis&lt;/i&gt;) on Eggplant Leaves Based on Multi-Spectral Image

Gray mold (Botrytis) is a common fungus disease on eggplants,it can reduce the production by 20-30% at worse. Most disease infestations are not evenly distributed across the cultivation area but in patches [1]. The usual method of prevention is spraying fungicide on entire field, which would requires an excessive amount of fungicide and resulting, increases cost of production, pollutes the environment, and improves of resistance fungal strains [2]. In fact, the fungicide can be spray only the area infected which is rather small on the early stage and it is fully capable of controlling disease spread. Therefore, rapid disease detection is the key. The accurate and effective detection method would be helpful for reducing the dosage of fungicide and preventing disease spread.