Control Of Rust Research Articles

Is virulence phenotype evolution driven exclusively by Lr gene deployment in French Puccinia triticina populations?

AbstractPuccinia triticina is a highly damaging wheat pathogen. The efficacy of leaf rust control by genetic resistance is mitigated by the adaptive capacity of the pathogen, expressed as changes in its virulence combinations (pathotypes). An extensive P. triticina population survey has been carried out in France over the last 30 years, describing the evolutionary dynamics of this pathogen in response to cultivar deployment. We analysed the data set for the 2006–2016 period to determine the relationship between the Lr genes in the cultivars and virulence in the pathotypes. Rust populations were dominated by a small number of pathotypes, with variations in most of the virulence frequencies related to the corresponding Lr gene frequencies in the cultivated landscape. Furthermore, the emergence and spread of a new virulence matched the introduction and use of the corresponding Lr gene (Lr28), confirming that the deployment of qualitative resistance genes is an essential driver of evolution in P. triticina populations. However, principal component analysis (PCA) revealed that certain pathotype–cultivar associations cannot be explained solely by the distribution of Lr genes in the landscape. This conclusion is supported by the predominance of a few pathotypes on some cultivars, with the persistence of several other compatible pathotypes at low frequencies. Specific interactions are not, therefore, sufficient to explain the distribution of virulence in rust populations. The hypothesis that quantitative interactions between P. triticina populations and bread wheat cultivars—based on differences in aggressiveness—is also a driver of changes in pathotype frequencies deserves further investigation.

Influence of spraying tips on the efficiency of chemical control of soybean rust

Asian rust is responsible for significant reductions in soybean yield. The application of fungicide is the main method of control of this disease, and to maintain the efficiency of phytosanitary treatment it is necessary to know several features of the application technology. Spray tips are fundamental for the quality of phytosanitary products application and exert a direct influence on spraying efficiency. The objective of this study was to evaluate the efficiency of different spray tips in spray deposition and leaf cover in the lower, middle and upper thirds of soybean plants in three distinct phenological stages. Another objective was to evaluate the efficiency of the commercial mixture trifloxystrobin + prothioconazole (FOX®), applied by different spray tips, in the control of Asian rust and soybean yield. The experiment was conducted for two agricultural years, and six spray tips were evaluated: TT 11001, TTJ60 11002, TXA 8003, 30HCX 12, GRD120 02 and GAT11002 in three fungicide applications with intervals of 15 days, in the phenological stages V6–V7, R1 and R4, using the working pressure of 5 bar and spray volume of 200 L ha−1. The coverage and deposition of spray promoted by all spray tips, in the three phenological stages of soybeans, were sufficient to provide satisfactory control of rust, with means of disease severity ranging from 1.69 to 4.70%, compared to the control (mean severity of 54.34%), without significant loss of yield in the sprayed plots. All evaluated spray tips can be recommended for use in spraying FOX® fungicide (trifloxystrobin + prothioconazole) in soybean crop for Asian rust control, when the spray volume applied is 200 L ha−1.

Impact of fungicide application volume on ASIAN rust control and soybean crop yield

Impact of fungicide application volume on ASIAN rust control and soybean crop yield

Interaction of varieties and fungicides across seasons and locations for the control of Asian soybean rust (Phakopsora pachyrhizi) in Southwestern Ethiopia

Soybean is emerging as an important legume and oil crop in Ethiopia. However, the crop has been facing serious threats from Asian Soybean Rust (ASR), causing significant damage to the crop and not allowing it to realize its potential. This study aimed to determine the interaction of three varieties with various fungicide treatments across two seasons and two locations to manage ASR. The experiment was laid out in a RCBD in a factorial [three soybean varieties (V) and six fungicides (F)] treatment combination at two locations (L) for two years (Y) with three replications. The analysis of variance across seasons revealed highly significant V × F × Y interactions for grain yield, and F × Y interactions for severity (%) and AUDPC; while efficacy was significant (P = 0.05). The V × Y interaction showed highly significant differences for AUDPC. Across locations, there were highly significant differences for V × F × L for grain yield and V × L for AUDPC. It was only AUDPC that showed significant (P = 0.05) for the V × F interaction. There were two rates (0.75 and 1 l ha−1) of the fungicide Opera Max that provided the best protection against ASR across locations, varieties, and seasons. The yield loss on the unsprayed control treatment ranged between 29 and 65%. The evidence generated from this study clearly demonstrates the importance of identifying the right variety, rates and types of fungicides for the control of ASR for higher production and productivity of soybean in Ethiopia.

Qualities of Soybean Grains Harvested on Crops Treated with Neem Seeds Extract in Field Conditions against Asian Rust

In soybean production, qualities of grains harvested are usually affected according to the development of diseases and control methods used in the field. This study aims to evaluate the impact of neem seeds extract (AENS) on soybean grains health after crops treatment in field conditions for the control against Asian rust. Experiment was conducted in Mimetala and Nkometou, located in the agroecological zone V of Cameroun. Three varieties of soybean (“Locale”, TGX 1835-10E and TGX1910-14E) were used in a completely randomized blocks design containing five treatments: T0 (control), T1, T2, T3 (25, 50, 100 g/L of extract respectively) and T4 (5.33 g/L of Plantineb 80wp). The disease was identified on the harvested grains; its incidence on those grains was evaluated and some biochemical parameters were assessed by extraction and determination of their contents. Many grains were attacked by Asian rust. The highest incidence was obtained in the seeds from untreated plots (35 %), compared to those from T1, T2, T3 (1.14; 1.07 and 0.95 % respectively). The different doses of AENS improved the content of all biochemical compounds tested in harvested grains compared with the T0 and T4 treatments. TGX1910-14E variety presented the highest content. In T3,grain contents in biochemical compounds were 415.17; 118.83; 118.33; 44.43; 36.53 and 10.83 mg/g of dry matter from total proteins, globulin, albumin, Glutelin, prolamin and glucide respectively. Meanwhile, in T4 treatments, grain contents were 403.49; 112.95; 112.78; 40.58; 33.90 and 9.91 mg/g of dry matter from the same compounds respectively. This study shows that the application of neem seeds extract on soybean crops for the control of Asian rust in field conditions at the maximum dose (e.g. 100 g/L) can improve the qualities of harvested grains. The neem extract as a natural substance should be used in integrated pest management of soybean and other crops.

Exome Sequencing from Bulked Segregant Analysis Identifies a Gene for All-Stage Resistance to Stripe Rust on Chromosome 1AL in Chinese Wheat Landrace 'Xiaohemai'.

Stripe rust caused by Puccinia striiformis f. sp. tritici is one of the most destructive diseases of wheat. Identifying novel resistance genes applicable for developing disease-resistant cultivars is important for the sustainable control of wheat stripe rust. Chinese wheat landrace 'Xiaohemai' ('XHM') is an elite germplasm line with all-stage resistance (ASR) effective against predominant Chinese P. striiformis f. sp. tritici races. In this study, we performed a bulked segregant analysis coupled with exome capture sequencing (BSE-seq) to identify a candidate genomic region strongly associated with stripe rust resistance on chromosome 1AL in 173 F2:3 lines derived from the cross 'XHM' × 'Avocet S'. The gene, designated as YrXH-1AL, was validated by a conventional quantitative trait locus analysis using newly developed Kompetitive allele-specific PCR (KASP) markers, explaining up to 48.50% of the phenotypic variance. By testing a secondary mapping population comprising 144 lines from the same cross at the seedling stage with prevalent P. striiformis f. sp. tritici race CYR34, YrXH-1AL was identified as a single Mendelian factor in a 1.5-cM interval flanked by KASP markers KP1A_484.33 and KP1A_490.09. This region corresponded to a 5.76-Mb genomic interval on 'Chinese Spring' chromosome 1AL. Furthermore, two cosegregating KASP markers showed high polymorphisms among 130 Chinese wheat cultivars and could be used for marker-assisted selection. Because no other Yr genes for ASR that originated from common wheat have been detected on chromosome 1AL, YrXH-1AL is likely a novel gene that can be incorporated into modern breeding materials to develop wheat cultivars with enhanced stripe rust resistance.

Spray nozzles and curtain of chains in fungicide application to control Asian soybean rust

The proper choice of spray nozzles and spray boom configuration is of paramount importance for fungicidal effectiveness, promoting better foliar coverage, especially in the lower canopy of the crop. In this sense, the present study evaluates the influence of fungicides applied with different spray nozzles, with and without curtain of chains, on Asian rust control and on the yield of soybean cultivar BMX Ativa RR. The experimental design was a randomized block, with four spray nozzles (Albuz ® ATR 1.0; Albuz ® ATR 0.5; Magnojet ® ADT 11002; and Magnojet ® CH100) and two spray boom configurations (with curtain of chains; and without curtain of chains). The experiment had four replicates and a control without fungicide application. The variables under study were the severity and control of Asian soybean rust, thousand grain weight, and soybean yield. The results indicate that using the curtain of chains in fungicide applications is a technically viable alternative to increase soybean yield. When used along with empty conical jet and triple flat jet nozzles, this technology is highly efficient in controlling Asian soybean rust.

Rust (Puccinia emaculata) Management and Impact on Biomass Yield in Switchgrass.

Rust, putatively caused by Puccinia emaculata, is a widespread and potentially damaging disease of switchgrass, a crop produced as feedstock for livestock and bioenergy. Azoxystrobin, chlorothalonil, and myclobutanil were applied at 1-, 2-, 3-, or 4-week intervals for 12 to 14 weeks to the vegetatively propagated switchgrass cultivar Cloud Nine to assess fungicide selection and application interval for the control of rust as well as the impact of this disease on switchgrass biomass yield. Although rust severity significantly differed among study years, azoxystrobin and myclobutanil were often equally and more effective than chlorothalonil at controlling rust, with superior disease control coming at shorter application intervals compared with extended application intervals. Year, product, application interval, and product × interval significantly impacted dry biomass yield, which was greatest in 2016 and lowest in 2014. Dry biomass yield protection was significantly better with azoxystrobin and myclobutanil applications than with chlorothalonil or no fungicide. Linear regression models with the final disease rating, as well as with the area under disease progress curve in each year, were significant, but coefficients of determination were low to moderate (0.21 < R2 < 0.60), indicating that rust response and subsequent disease impact on dry biomass yield were impacted by other factors. From our models, an estimated 3 to 5% biomass decline was calculated for each 10% increment in rust-related leaf necrosis observed at the final September rating date. With rust-related leaf necrosis ≥80% by 1 September in each of 4 study years, biomass yield may be reduced by 24 to 40% if rust problems are not managed in switchgrass crops.

Association of hydrogen peroxide with commercial fungicide formulations in the control of Asian soybean rust

ABSTRACT: In recent years, there have been reductions in the efficacy of the fungicidal control of Phakopsora pachyrhizi, thereby hindering the management of soybean rust and compromising crop yield. This study evaluated the effects of incorporating hydrogen peroxide (H2O2) in commercial fungicide formulations on the control of soybean rust. We conducted two experiments, one of which was performed in a greenhouse environment and the other under field conditions. In both environments, we examined the following four control programs using commercial fungicide formulations: (I) azoxystrobin + cyproconazole (quinone outside inhibitor [QoI] + demethylation inhibitor [DMI]); (II) picoxystrobin + cyproconazole (QoI + DMI); (III) pyraclostrobin + epoxiconazole + fluxapyroxad (QoI + DMI + succinate dehydrogenase inhibitor); and (IV) water (H2O) (program without fungicide application), combined with the incorporation of (i) H2O2; (ii) mancozeb (positive control I); (iii) chlorothalonil (positive control II); or (iv) water (H2O) alone. Analyses of infected leaf area and grain yield revealed that the addition of H2O2 to the formulations of DMI and QoI fungicides led to a reduction in disease severity of between 33% and 44% relative to the effects of these products used alone, as well as an increase in yield and SPAD values. The use of H2O2 and multi-site fungicides alone failed to provide effective control of soybean rust. In addition to enhancing the efficacy of disease control, the use of H2O2 associated with commercial fungicide mixtures was shown to be a potential tool for the management of fungicide resistance and reduction in losses from Asian soybean rust.

Effect of fungicides and biological products in controlling rust and gray mold in grapevines

Grape rust and gray mold are diseases in grapevines with high destructive potential. In this study, the effectiveness of different fungicides and biological products in controlling these diseases was evaluated using the cultivar “Niágara Rosada” in the municipality of Louveira-SP, from February to April 2017. A randomized block design was used, with 10 treatments and four replicates and five plants per plot. Each treatment was applied nine times at weekly intervals, with application volumes in the range of 400–1000 L/ha. The evaluation criterion for rust was the severity, based on the percentage of leaf area affected by the disease (0 to 100%), whereas gray mold was evaluated using the incidence of diseased bunches (0 to 100%). All treatments were effective in controlling both diseases and significantly reduced the disease incidence in the experimental plot compared with that in the control plots. The best rust control was obtained by treating the plants with boscalide+pyraclostrobin (1 L c.p./ha), which was superior to fluxapyroxade+pyraclostrobin (0.5 L) + Bacillus amyloliquefaciens (0.5 kg), B. amyloliquefaciens (0.5 kg), Melaleuca alternifolia essential oil (1.5 L), and dimoxystrobin+boscalide (1 L). The plants treated with fluxapyroxad+pyraclostrobin (0.5 L) + B. amyloliquefaciens (0.5 kg) had a lower incidence of gray mold than did those treated with dimoxystrobin+boscalide (1 L), boscalide+kresoxim methyl (0.5 L), and piremethanil (1.5 L). These results suggest that the use of M. alternifolia essential oil and B. amyloliquefaciens may represent an important tool for the management of rust and gray mold in grapevines.

Estimativas da eficácia de fungicidas para controle da ferrugem asiática da soja com base em dados da AACPD ou da severidade final da doença

ABSTRACT Data from experiments conducted in the field during four growing seasons aiming at the chemical control of soybean rust caused by Phakopsora pachyrhizi, the control values calculated for the area under the disease progress curve (AUDPC) were compared with those of the final severity. Data were analyzed according to a factorial experiment: (i) treatments with fungicides and (ii) rust control. Out of 70 treatments, the control was always lower when calculated with the AUDPC than with the final severity. In the general means for four growing seasons, the AUDPC control was of 48.5 (range 36 to 65%) and for calculation with the final severity 43.25% (range 29 to 66%). It can be concluded that, in the case of soybean rust, the control calculation shows advantage when performed with final severity data.

Spectral responses at visible and near-infrared wavelengths of soybean plants to fungicides

ABSTRACT: The study evaluated the efficacy and soybean spectral responses to fifteen foliar fungicide mixtures labeled to control Asian soybean rust. Canopy level reflectance was measured using a multispectral camera onboard a multirotor drone before and two hours after each spray. The third application of fungicides improved control of soybean rust and increased yield. Nevertheless, up to three consecutive foliar fungicides applications did not affect the reflectance of soybean plants at visible and infrared wavelengths. Thus, drones can be a viable strategy for data acquisition regardless of the application of the fungicides.

Combined use of foliar zinc fertilisation, thiamethoxam and propiconazole does not reduce their effectiveness for enriching zinc in wheat grains and controlling insects and disease

Agronomic biofortification is possible through foliar zinc fertilisation around the earing and early milk stage of wheat. Farmers can be encouraged to apply foliar zinc fertilisation if there is yield enhancement or if it is compatible with other pesticides which are used during these stages to control aphid and stripe rust. To investigate the effectiveness of tank-mix applications of fertiliser and pesticide for enriching grain zinc and controlling the spread of aphid and stripe rust, studies were conducted at Punjab Agricultural Univeristy, Ludhiana, India for 4 years (2017–18 to 2020–21). We tested tank-mixing of zinc (0.5% ZnSO4.7H2O) + thiamethoxam 25 WG (50 g/ha), zinc + propiconazole (500 mL/ha) and zinc + thiamethoxam + propiconazole with one foliar application at the milk stage and two foliar applications at the flag leaf and milk stages. We did not find any adverse effect of tank-mix application of zinc sulfate, thiamethoxam and propiconazole on zinc enrichment in grains, nor in aphid and stripe rust control. The grain zinc enhancement was 99.8–114.9, 100.2–112.1 and 98.0–115.5% with application of foliar Zn, foliar Zn + thiamethoxam and foliar Zn + thiamethoxam and propiconazole respectively. We also found 5.74% increased grain yield with foliar Zn + thiamethoxam and 7.24% increased grain yield in foliar Zn + thiamethoxam + propiconazole. Better net returns in combining Zn + thiamethoxam + propiconazole were also recorded. The results advocate for the tank-mix application of Zinc + thiamethoxam + propiconazole for pest management and Zn biofortification.

WHEAT STRIPE RUST AND INTEGRATION OF SUSTAINABLE CONTROL STRATEGIES IN CHINA

<List> <ListItem><ItemContent> • Stripe rust caused substantial yield losses in China. </ItemContent></ListItem> <ListItem><ItemContent> • <i>P. striiformis</i> is highly variable and the change from avirulence to virulence. </ItemContent></ListItem> <ListItem><ItemContent> • Different comprehensive control strategies were adopted in different epidemic region. </ItemContent></ListItem></List> Stripe (yellow) rust caused by <i>Puccinia striiformis</i> f. sp. <i>tritici</i> occurs in almost all wheat-producing regions of the world. Severe countrywide epidemics in China have caused substantial yield losses. Growing resistant cultivars is the best strategy to control this disease but the pathogen can overcome resistance in wheat cultivars. The high variation in the virulence of the pathogen combined with the large areas of susceptible wheat cultivars enables the pathogen population to increase rapidly and disperse over long distances under favorable environmental conditions, resulting in severe pandemics within cropping seasons. Current stripe rust control measures are based on many years of research including the underlying epidemiology regarding year-to-year survival of the pathogen, pathways of pathogen dispersal within seasons and years, the role of <i>P. striiformis</i> sexual hybridization, the use of resistance sources in breeding programs, and year-round surveillance of national wheat crops that are present in different parts of the country throughout the year. All these strategies depend on accurate prediction of epidemics, more precise use of fungicides to meet national requirements and better deployment of resistance genes. New ideas with potential application in sustainable protection of stripe rust include negative regulatory gene editing, resistance gene overexpression and biological control based on microbiomes.

Spray solution deposition and Asian rust control in soybean cultivars

ABSTRACT The control of Asian soybean rust depends on fungicide efficacy and the application technology; however, the leaf architecture of soybean cultivars may also interfere in disease control. This study aimed to evaluate Asian rust control and fungicide deposition using spray nozzles in three soybean cultivars. A randomized block design was used, with treatments arranged in a split-plot scheme; the plots were three soybean cultivars (SYN 1561 IPRO, M6410 IPRO, and M6210 IPRO) and the subplots three spray nozzles (11002 BD, AIXR 110015 and TTJ60 11002), in addition to a control with no fungicide application, and four replicates. The volume median diameter, droplet coverage, leaf area index, area under the disease progress curve, 1,000-grain weight and crop yield were evaluated. The 11002BD and AIXR11005 nozzles provided better spray deposition in cultivars with lower leaf area indexes at the R1 phenological stage. Nozzles 11002BD, AIXR110015 and TTJ60 ensured better management of Asian rust than that of the control treatment, regardless of leaf area index. Cultivar SYN1561 obtained the largest grain yield and highest leaf area index in the season with the highest rainfall, regardless of the spray nozzle used.

Potential of thaxtomin A for the control of the Asian soybean rust

Several strategies are required to achieve satisfactory control of Asian soybean rust (ASR) caused by the fungus Phakopsora pachyrhizi. The use of resistance inducers represents a helpful alternative for management of this disease, since they can present good results when included in an integrated ASR management programme. The aim of this study was to investigate the effect of the partially purified phytotoxin thaxtomin A (PPT) in the induction of resistance to P. pachyrhizi in soybean plants and the direct effect on urediniospore germination. Detached soybean leaves were used to test the induction of resistance. They were treated with PPT 72 h before inoculation with the fungus. The disease severity was evaluated after 12 days. For gene expression analysis, leaf samples were collected 24 h after the application of the inducer. The results showed that PPT had a direct effect on spore germination. A concentration of 100 µg PPT mL−1 inhibited the germination of P. pachyrhizi urediniospores by 64.7%. The phytotoxin was also able to reduce the severity of ASR in detached leaves, possibly through the activation of defence mechanisms related to the jasmonate/ethylene pathways. The application of PPT resulted in upregulation of the expression of the ACC gene, the precursor of ethylene biosynthesis, which is involved in one of the three signalling pathways of defence in plants. Thus, these results suggest that the partially purified thaxtomin A is a potential agent for the control of ASR.

Combined linkage and association mapping reveals two major QTL for stripe rust adult plant resistance in Shaanmai 155 and their haplotype variation in common wheat germplasm

The development and deployment of diverse resistance sources in new wheat cultivars underpin the durable control of stripe rust. In the present study, two loci for adult plant resistance (APR), QYrSM155.1 and QYrSM155.2, were identified in the Chinese wheat breeding line Shaanmai 155. QYrSM155.1 was mapped to a 3.0-cM interval between the single-nucleotide polymorphism (SNP) markers AX-109583610 and AX-110907562 on chromosome arm 2BL. QYrSM155.2 was mapped to a 2.1-cM interval flanked by the SNP markers AX-110378556 and AX-86173526 on chromosome arm 7AS. A genome-wide association study was used to identify markers associated with APR in a panel of 411 spring wheat lines. Thirteen and 11 SNPs were significantly associated with QYrSM155.1 and QYrSM155.2, respectively, corresponding to physical intervals of 653.75–655.52 Mb on 2BL and 81.63–83.93 Mb on 7AS. To characterize the haplotype variation and the distribution of these QTL, haplotype analysis was performed based on these SNPs in an independent panel of 1101 worldwide wheat accessions. Three major haplotypes (2B_h1, 2B_h2, and 2B_h3) for QYrSM155.1 and four major haplotypes (7A_h1, 7A_h2, 7A_h3, and 7A_h4) for QYrSM155.2 were identified. Accessions individually harboring QYrSM155.1_h1 and QYrSM155.2_h1 haplotypes and their combination displayed resistance. Additional assays of 1306 current Chinese cultivars and breeding lines using markers flanking QYrSM155.1 and QYrSM155.2 indicated that the resistance haplotypes of the two QTL were present in respectively 1.45% and 14.16% of lines. Increasing resistance haplotype frequencies at these two loci using marker-assisted selection should benefit wheat production in China.

Asian Rust Severity in Soybean Sown in December and February in Mato Grosso State

The objective of this work was to assess the effect of December sowing time with February on the Asian soybean rust severity. In on-farm trials two soybean treatments sowing in December (2020) (DSS.) and February (2021) (FSS) were assessed for Asian soybean rust severity in 24 sites, in three regions of Mato Grosso state. The DSS treatment was established in the growers commercial farms and the FSS in a 5 ha area sown specifically for this treatment. The DSS treatment was conducted in 16 sites and the FSS in eigth. For rust control fungicides with efficacy higher than 60% were sprayed consisting of DMIs, QoIs and SDHIs in double or triple mixtures, always added by multisites (chlorothalonil, mancozeb, or copper oxychloride). About eighty soybean leaflets from four plots repetitiond, demarcated at random in each field, were taken in each smpling. In laboratory leaflet severity was appraised and area under disease progress curve (AUDPC) calculated. Related to DSS, the AUDPC overall mean was 174 units and receiving 6.9 fungicide spraying and for FSS 26 units with 4.8 fungicide sprayings. Our results reinforce that the sowing time can be changed from the end of December to February to maintain soybean crop sustainability.

Efficacy of delayed entry low branch sanitation pruning in preventing mortality of western white pine infected with white pine blister rust

White pine blister rust, caused by the fungus Cronartium ribicola J. C. Fisch., is a virulent mortality agent of five-needle pines like western white pine (Pinus monticola D. Don.). For decades, low branch pruning has been recommended as a control by removing cankers that can migrate from infected branches to the tree stem and kill the host. These recommendations are mainly based on studies done on eastern white pine (Pinus strobus L.), or on western white pine growing primarily in the Interior Pacific Northwest of the United States. It is not clear whether these recommendations are transferable to geographically and climatically dissimilar Pacific coastal areas, where pruning often shows little benefit in commercial forest plantations. We summarize over 30 years of post-treatment data from coastal and interior sites in British Columbia. Sanitation pruning was done on 12–22-year-old stands using one or two pruning lifts and infection and mortality were tracked over the subsequent decades. Our results show that while pruning had little negative effect on treated tree height or diameter growth, mortality was not significantly different between treated and untreated groups across all sites. Cumulative mortality after three decades was >80% for coastal sites, and nearly 60% for the interior site, indicating a lack of treatment efficacy. Our results differ from earlier shorter duration studies and those from other jurisdictions. It is clear that delaying pruning until trees are older and carrying many existing branch and stem infections results in ineffective control of rust in coastal white pine stands.

Strategies for Coffee Leaf Rust Management in Organic Crop Systems

Coffee is a crop of great economic importance in many countries. The organic coffee crop stands out from other production systems by aiming to eliminate the use of synthetic fertilizers and pesticides. One of the most important limitations in the organic system is the management of diseases, especially coffee rust, which is considered the main disease of this crop. Coffee rust causes a production slump of up to 50%, significantly affecting the profitability of coffee growers. This work aims to review the integrated rust management in organic coffee crop in different producing countries. Regarding the disease management strategies, this review addresses the use of rust-resistant cultivars, cultural management, biological control, use of plant extracts, and chemical rust control by cupric fungicides. Considering the importance of the organic system, the increase in world coffee consumption, and the potential market for this kind of coffee, this review may help researchers and producers looking for alternative strategies to control rust in an organic coffee cultivation system.