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Samples of black pepper root with the presence of galls from the most southern region of the State of Bahia, Brazil, were characterized biochemically and morphologically using three criteria: i) observation of the anterior region of the males; ii) analysis of female perineal configuration and iii) polyacrylamide gel electrophoresis technique. Meloidogyne arenaria was found. This is the first report of this pathosystem in the State.

Brazilian forest-based industries are supported by more than 5.5 million hectares of Eucalyptus growing under different climatic conditions with different degrees of favourability for rust Puccinia psidii, including both traditional and expanding areas, where such disease is of major concern for the industry, foresters and scientists. The main objective of this study was to define favourable climatic zones for Eucalyptus rust in Brazil with the following aims: (i) to develop a spatial method for estimating the mean night-time temperature ( Tng); (ii) to assess and validate a Eucalyptus rust model; and (iii) to map Eucalyptus rust favourability zones in Brazil based on the proposed model. A straightforward method, based only on latitude, day of the year, maximum and minimum air temperatures, was developed to estimate Tng, which is a key variable for a proper application of Ruiz rust model. Based on 37 field experiments with natural rust occurrence, it was observed that climatic conditions are determining factors for disease severity. Significant correlations between disease severity observed in the field and climatic conditions were found: a negative correlation with temperature ( r = .50, p < .01) and a positive correlation with relative humidity ( r = .89, p < .0001). A significant correlation ( r = .81, p < .0001) between the normalized infection index, produced from Ruiz model, and the average rust score was also observed. Once the model was validated under field conditions, it was applied using historical average data of air temperature and leaf wetness duration to obtain monthly Eucalyptus rust favourability maps for the whole country. These final maps show that favourable climatic zones for Eucalyptus rust are extremely dynamic, with high temporal and spatial variability in Brazil and that climatic conditions should be considered for expansion of Eucalyptus to new areas, in breeding programmes, and for defining the most suitable seasons for forest establishment in each climate of the country. These results provide forestry managers with practical tools to reduce uncertainty about the expected severity of Eucalyptus rust in Brazil. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Phytopathology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fusarium wilt, caused by Fusarium oxysporum f. sp. spinaciae, causes a significant challenge on vegetative spinach and seed production. Addressing this issue necessitates continuous research focused on innovative treatments and protocols through comprehensive bioassays. Recent studies have highlighted the potential of plant-based compounds in controlling fungal diseases. The present work aims to conduct a series of experiments, encompassing both in vitro and in planta assessments, to investigate the biocontrol capabilities of different essential oils (EOs) at various application rates, with the ultimate goal of reducing the incidence of Fusarium wilt in spinach. The inhibitory effect of four plant EOs (marjoram, thyme, oregano, and tea tree) was initially assessed on the spore germination of five unknown Fusarium strains. The outcomes revealed diverse sensitivities of Fusarium strains to EOs, with thyme exhibiting the broadest inhibition, followed by oregano at the highest concentration (6.66 μL/mL) in most strains. The tested compounds displayed a diverse range of median effective dose (ED50) values (0.69 to 7.53 µL/mL), with thyme and oregano consistently showing lower ED50 values. The direct and indirect inhibitory impact of these compounds on Fusarium mycelial growth ranged from -14% to -100%, wherein thyme and oregano consistently exhibiting the highest effectiveness. Following the results of five distinct inoculation approaches and molecular identification, the highly pathogenic strain F-17536 (F. oxysporum f.sp. spinaciae) was chosen for Fusarium wilt assessment in spinach seedlings, employing two promising EO candidates through seed and soil treatments. Our findings indicate that colonized grain (CG) proved to be a convenient and optimal inoculation method for consistent Fusarium wilt assessment under greenhouse conditions. Seed treatments with thyme and oregano EOs consistently resulted in significantly better disease reduction rates, approximately 54% and 36% respectively, compared to soil treatments (P > 0.05). Notably, thyme, applied at 6.66 µL/mL, exhibited a favorable emergence rate (ERI), exceeding seven, in both treatments, emphasizing its potential for effective disease control in spinach seedlings without inducing phytotoxic effects. This study successfully transitions from in vitro to in planta experiments, highlighting the potential incorporation of EOs into integrated disease management for Fusarium wilt in spinach production. [ABSTRACT FROM AUTHOR]

Essential oils play an important role in the fight against plant pathogens. Clove essential oils are widely used as antifungal, antibacterial, insecticidal, and antioxidant agents. To increase its solubility and reduce its volatility, clove essential oil was encapsulated in β cyclodextrin, using the freeze-drying method at a weight ratio of 16:84. The composition of clove essential oil was evaluated using gas chromatographymass spectrometry (GC-SM). Gas chromatography-mass spectrometry analysis revealed the presence of 11 components, representing 98.7% of the essential oils. The major component was eugenol (79.7%), followed by eugenyl acetate (16.3%). The antifungal activity of clove essential oil and its inclusion complex with β cyclodextrin was tested against an Algerian isolate of Fusarium oxysporum f.sp radicis lycopersici (FORL) and a reference strain, Fusarium oxysporum f.sp lycopersici race 2 (FOL) in liquid medium. The obtained results demonstrated that the antifungal efficiency of clove essential oil against FORL and FOL enhanced after encapsulation in β-cyclodextrin. A significant difference between the inhibition rates obtained with free clove essential oil and those obtained with the inclusion complex (β-cyclodextrin-clove oil) was observed for the concentrations studied. [ABSTRACT FROM AUTHOR]

Modern data analysis typically involves the fitting of a statistical model to data, which includes estimating the model parameters and their precision (standard errors) and testing hypotheses based on the parameter estimates. Linear mixed models (LMMs) fitted through likelihood methods have been the foundation for data analysis for well over a quarter of a century. These models allow the researcher to simultaneously consider fixed (e.g., treatment) and random (e.g., block and location) effects on the response variables and account for the correlation of observations, when it is assumed that the response variable has a normal distribution. Analysis of variance (ANOVA), which was developed about a century ago, can be considered a special case of the use of an LMM. A wide diversity of experimental and treatment designs, as well as correlations of the response variable, can be handled using these types of models. Many response variables are not normally distributed, of course, such as discrete variables that may or may not be expressed as a percentage (e.g., counts of insects or diseased plants) and continuous variables with asymmetrical distributions (e.g., survival time). As expansions of LMMs, generalized linear mixedmodels (GLMMs) can be used to analyze the data arising from several non-normal statistical distributions, including the discrete binomial, Poisson, and negative binomial, as well as the continuous gamma and beta. A GLMM allows the data analyst to better match the model to the data rather than to force the data to match a specificmodel. The increase in computer memory and processing speed, together with the development of user-friendly software and the progress in statistical theory and methodology, has made it practical for non-statisticians to use GLMMs since the late 2000s. The switch from LMMs to GLMMs is deceptive, however, as there are several major issues that must be thought about or judged when using a GLMM, which are mostly resolved for routine analyses with LMMs. These include the consideration of conditional versus marginal distributions and means, overdispersion (for discrete data), the model-fitting method [e.g., maximum likelihood (integral approximation), restricted pseudo-likelihood, and quasi-likelihood], and the choice of link function to relate the mean to the fixed and random effects. The issues are explained conceptually with different model formulations and subsequently with an example involving the percentage of diseased plants in a field study with wheat, as well as with simulated data, starting with a LMM and transitioning to a GLMM. A brief synopsis of the published GLMM-based analyses in the plant agricultural literature is presented to give readers a sense of the range of applications of this approach to data analysis. [ABSTRACT FROM AUTHOR]

In this work, we studied the direct and indirect plant protection effects of an Artemisia absinthium essential oil (AEO) on tomato seedlings against Fusarium oxysporum sp. oxysporum radicis lycopersici (Fol). AEO exhibited a toxic effect in vitro against Fol. Additionally, tomato seedlings germinated from seeds pretreated with AEO and grown hydroponically were protected against Fol. Plant disease symptoms, including, water and fresh weight loss, tissue necrosis, and chlorosis were less pronounced in AEO-treated seedlings. AEO also contributed to plant defenses by increasing callose deposition and the production of reactive oxygen species (ROS) on seed surfaces without affecting seed germination or plant development. The essential oil seed coating also primed a durable tomato seedling defense against the fungus at later stages of plant development. RNA-seq and metabolomic analysis performed on seedlings after 12 days showed that the AEO treatment on seeds induced transcriptomic and metabolic changes. The metabolomic analysis showed an induction of vanillic acid, coumarin, lycopene, oleamide, and an unknown metabolite of m/z 529 in the presence of Fol. The StNRPD2 gene, the second largest component of RNA polymerases IV and V directly involved in de novo cytosine methylation by RNA-directed DNA methylation (RdDM), was highly induced in the presence of AEO. The host methionine cycle (MTC) controlling trans-methylation reactions, was also altered by AEO through the high induction of S-adenosyl methionine transferases (SAMts). Our results suggest that AEO treatment could induce de novo epigenetic changes in tomato, modulating the speed and extent of its immune response to Fol. The EO-seed coating could be a new strategy to prime durable tomato resistance, compatible with other environmentally friendly biopesticides. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Global climate models that incorporate carbon sources and sinks usually consider that forest uptake of carbon is in a state of equilibrium. Both historical and paleoecological records suggest that this is commonly not the case for Amazonia. Here, the impacts of colonial practices on Amazonian Indigenous peoples and forests are reviewed. Human activities affect forests' successional stages, trajectories, and species composition. By increasing the spatial coverage of paleoecological records that focus on pre‐ and post‐Columbian periods, the long‐term interactions between humans and Amazonian forests and their role in affecting Earth's climate may be better understood. Summary: Legacy effects left by the activities of Indigenous people in Amazonia are well known. Although severe, widespread, and recently occurring, the impacts left post‐1492 CE have been less investigated. We review the impact of colonial practices on Indigenous peoples and Amazonian forests. We suggest that forests comprise the sum of their past events, in a mosaic of different cumulative successional trajectories depending on the type, frequency, intensity, and timing of human influence. In regions with a history of minimal human influence, old‐growth species sensitive to fire would be the dominant landscape. In regions with high pre‐Columbian and low colonial influence, old‐growth forests carrying pre‐Columbian ecological legacies would be prevalent. Regions occupied by Indigenous groups post‐1492 CE would also carry similar ecological legacies. In regions influenced by the Jesuits, mid‐successional forests are expected to be enriched with cacao trees. In regions of latex extraction during the rubber boom, mid‐growth forests would present high abundances of early and mid‐successional species and depletion of some species. In deforested areas, we expect early successional forests with influence of exotic useful species. This patchwork of history probably plays a large role in shaping today's forests, and the biodiversity and carbon dynamics documented within them. Paleoecological work focusing on the last millennium, although scarce, has the potential to detect these mosaics of past human influence, and they should be considered when estimating forest ages and successional stages across the basin. [ABSTRACT FROM AUTHOR]

The fungal genus Fusarium contains many important plant pathogens as well as endophytes of wild and crop plants. Globally, Fusarium toxins in food crops are considered one of the greatest food safety concerns. Their occurrence has become more pronounced in Africa in recent times. Among the major Fusarium mycotoxins with food and feed safety concerns, zearalenone is frequently detected in finished feeds and cereals in Africa. However, the impact of indigenous agricultural practices (pre‐ and postharvest factors) and food processing techniques on the prevalence rate of Fusarium species and zearalenone occurrence in food and feed have not been collated and documented systematically. This review studies and analyzes recent reports on zearalenone contamination in maize and other cereal products from Africa, including its fungi producers, agronomic and climate variables impacting their occurrences, preventive measures, removal/decontamination methods, and legislations regulating their limits. Reports from relevant studies demonstrated a high prevalence of F. verticillioides and F. graminearum as Africa's main producers of zearalenone. Elevated CO2 concentration and high precipitation may carry along an increased risk of zearalenone contamination in maize. African indigenous processing methods may contribute to reduced ZEA levels in agricultural products and foods. Most African countries do not know their zearalenone status in the food supply chain and they have limited regulations that control its occurrence. [ABSTRACT FROM AUTHOR]

Copyright of Nativa is the property of Revista Nativa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To establish the favorable or unfavorable climatic conditions for the emergence and development of Black Sigatoka in a banana-growing area within the influence zone of the Teapa weather station (27004) in Tabasco, Mexico. Design/Methodology/Approach: We analyzed temperature data for n=59 years (1961-2019) at the Teapa weather station (27044) in Tabasco, as reported by IMTA (2009) and the Servicio Meteorológico Nacional (until 2019). Relative humidity was calculated using the equation developed by Allen et al. (2006). We also established the favorable or unfavorable climatic conditions for the development of Black Sigatoka in Teapa by resorting to the favorability typology posited by Júnior et al. (2008). Results: There are no highly favorable climatic conditions for the incidence and development of this disease. Overall, spring and summer are the less favorable months, while fall and winter offer more favorable conditions. Study Limitations/Implications: This study should be replicated in other banana-growing areas of Tabasco, since both temperature and relative humidity may differ and, consequently, the frequency of the disease may vary. Findings/Conclusions: October and March are the most favorable months for Black Sigatoka occurrence. Therefore, comprehensive management and control programs should be designed for this period. [ABSTRACT FROM AUTHOR]

Root-knot nematodes (RKNs), particularly Meloidogyne incognita, are among the most damaging and prevalent agricultural pathogens due to their ability to infect roots of almost all crops. The best strategy for their control is through the use of resistant cultivars. However, laborious phenotyping procedures make it difficult to assess nematode resistance in breeding programs. For common bean, this task is especially challenging because little has been done to discover resistance genes or markers to assist selection. We performed genome-wide association studies and quantitative trait loci mapping to explore the genetic architecture and genomic regions underlying the resistance to M. incognita and to identify candidate resistance genes. Phenotypic data were collected by a high-throughput assay, and the number of egg masses and the root-galling index were evaluated. Complex genetic architecture and independent genomic regions were associated with each trait. Single nucleotide polymorphisms on chromosomes Pv06, Pv07, Pv08, and Pv11 were associated with the number of egg masses, and SNPs on Pv01, Pv02, Pv05, and Pv10 were associated with root-galling. A total of 216 candidate genes were identified, including 14 resistance gene analogs and five differentially expressed in a previous RNA sequencing analysis. Histochemical analysis indicated that reactive oxygen species might play a role in the resistance response. Our findings open new perspectives to improve selection efficiency for RKN resistance, and the candidate genes are valuable targets for functional investigation and gene editing approaches., (© 2021 The Authors. The Plant Genome published by Wiley Periodicals LLC on behalf of Crop Science Society of America.)

Changing atmospheric composition represents a source of uncertainty in our assessment of future disease risks, particularly in the context of mycotoxin producing fungal pathogens which are predicted to be more problematic with climate change. To address this uncertainty, we profiled microbiomes associated with wheat plants grown under ambient vs. elevated atmospheric carbon dioxide concentration [CO2] in a field setting over 2 years. We also compared the dynamics of naturally infecting versus artificially introduced Fusarium spp. We found that the well-known temporal dynamics of plant-associated microbiomes were affected by [CO2]. The abundances of many amplicon sequence variants significantly differed in response to [CO2], often in an interactive manner with date of sample collection or with tissue type. In addition, we found evidence that two strains within Fusarium - an important group of mycotoxin producing fungal pathogens of plants - responded to changes in [CO2]. The two sequence variants mapped to different phylogenetic subgroups within the genus Fusarium, and had differential [CO2] responses. This work informs our understanding of how plantassociated microbiomes and pathogens may respond to changing atmospheric compositions. [ABSTRACT FROM AUTHOR]

Seed is a critically important basic input of agriculture, because sowing healthy seeds is essential to food production. Using high quality seed enables less use of synthetic pesticides in the field. Seedborne pathogens can reduce yield quantity and quality of the crops produced. Seed treatments protect plant seedlings from pathogen attacks at emergence and at the early growth stages, contributing to healthy crop plants and good yield. However, there is increased concern about the application of synthetic pesticides to seeds, while alternatives are becoming increasingly addressed in seedborne pathogen research. A series of strategies based on synthetic fungicides, natural compounds, biocontrol agents (BCAs), and physical means has been developed to reduce seed contamination by pathogens. The volume of research on seed treatment has increased considerably in the past decade, along with the search for green technologies to control seedborne diseases. This review focuses on recent research results dealing with protocols that are effective in the management of seedborne pathogens. Moreover, the review illustrated an innovative system for routine seed health testing and need-based cereal seed treatment implemented in Norway. [ABSTRACT FROM AUTHOR]

Click chemistry is widely used for the efficient synthesis of 1,4-disubstituted-1,2,3-triazole, a well-known scaffold with widespread biological activity in the pharmaceutical sciences. In recent years, this magic ring has attracted the attention of scientists for its potential in designing and synthesizing new antifungal agents. Despite scientific and medical advances, fungal infections still account for more than 1.5 million deaths globally per year, especially in people with compromised immune function. This increasing trend is definitely related to a raise in the incidence of fungal infections and prevalence of antifungal drug resistance. In this condition, an urgent need for new alternative antifungals is undeniable. By focusing on the main aspects of reaction conditions in click chemistry, this review was conducted to classify antifungal 1,4-disubstituted-1,2,3-triazole hybrids based on their chemical structures and introduce the most effective triazole antifungal derivatives. It was notable that in all reactions studied, Cu(I) catalysts generated in situ by the reduction in Cu(II) salts or used copper(I) salts directly, as well as mixed solvents of t-BuOH/H 2 O and DMF/H 2 O had most application in the synthesis of triazole ring. The most effective antifungal activity was also observed in fluconazole analogs containing 1,2,3-triazole moiety and benzo-fused five/six-membered heterocyclic conjugates with a 1,2,3-triazole ring, even with better activity than fluconazole. The findings of structure-activity relationship and molecular docking of antifungal derivatives synthesized with copper-catalyzed azide-alkyne cycloaddition (CuAAC) could offer medicinal chemistry scientists valuable data on designing and synthesizing novel triazole antifungals with more potent biological activities in their future research., (© 2024 John Wiley & Sons Ltd.)

Copyright of Scientia Agropecuaria is the property of Scientia Agropecuaria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

There is still considerable controversy about the relative risk of mycotoxin exposure associated with the consumption of organic and conventional cereals. Using validated protocols, we carried out a systematic literature review and meta-analyses of data on the incidence and concentrations of mycotoxins produced by Fusarium, Claviceps, Penicillium, and Aspergillus species in organic and conventional cereal grains/products. The standard weighted meta-analysis of concentration data detected a significant effect of production system (organic vs. conventional) only for the Fusarium mycotoxins deoxynivalenol, with concentrations ∼50% higher in conventional than organic cereal grains/products (p < 0.0001). Weighted meta-analyses of incidence data and unweighted meta-analyses of concentration data also detected small, but significant effects of production system on the incidence and/or concentrations of T-2/HT-2 toxins, zearalenone, enniatin, beauvericin, ochratoxin A (OTA), and aflatoxins. Multilevel meta-analyses identified climatic conditions, cereal species, study type, and analytical methods used as important confounding factors for the effects of production system. Overall, results from this study suggest that (i) Fusarium mycotoxin contamination decreased between the 1990s and 2020, (ii) contamination levels are similar in organic and conventional cereals used for human consumption, and (iii) maintaining OTA concentrations below the maximum contamination levels (3.0 μg/kg) set by the EU remains a major challenge., (© 2024 The Authors. Comprehensive Reviews in Food Science and Food Safety published by Wiley Periodicals LLC on behalf of Institute of Food Technologists.)

Perennial ryegrass (Lolium perenne L.) is a valuable forage and soil stabilisation crop. Perennial crops have long been associated with good environmental performance and ecosystem stability. Vascular wilt diseases caused by Fusarium species are the most damaging plant diseases affecting both woody perennials and annual crops. Therefore, the aim of the present study was the assessment of the preventive and growth-promoting effects of carvacrol against Fusarium oxysporum, F. solani, and F. nivale (phylogenetically analyzed on the basis of internal transcribed spacer (ITS) regions) causing vascular wilt of ryegrass in vitro and under greenhouse conditions. To accomplish this aim, various parameters were monitored including coleoptile development, rhizogenesis, the incidence of coleoptile lesions, disease index, the visual appearance of ryegrass health, ryegrass organic matter and soil fungal load. The results obtained showed that F. nivale was highly harmful to ryegrass seedlings compared to other Fusarium species. Furthermore, carvacrol with 0.1 and 0.2 mg/mL protected significantly the seedlings against Fusarium wilt diseases both in vitro and in the greenhouse. Simultaneously, carvacrol also functioned as a seedling growth promoter, as is reflected in all monitored parameters, such as the recovery of seedling height and root length, and the development of new leaf buds and secondary roots. Carvacrol proved to be effective plant growth promoter and a bio-fungicide against Fusarium vascular diseases. [ABSTRACT FROM AUTHOR]

The genetic diversity of Coffea canephora Pierre ex A. Froehner present in old seminal crops must be characterized because it represents a source of genetic variability for breeding programs. In this study, the genetic diversity of 388 half‐sib families of C. canephora, collected from Espírito Santo, Brazil, were assessed for their phenotypic traits. The data were obtained in a trial planted in April 2018 with five commercial clones as controls. Vegetative development was evaluated based on plant height, stem diameter, and average height and diameter growth rates. Abiotic (drought) and biotic (rust, leaf miner, and mealybug) stresses were evaluated by a rating scale. The phenotypic variability of the population was detected for all traits, and divergent clusters of families were identified. Negative correlations indicated that adverse conditions hampered the early development of the coffee plants. Groups of families should be investigated for breeding programs according to adequate development even under stressful conditions. These results show the importance of preserving the germplasm of old crops in the south of Espírito Santo as a source of genetic resources for coffee breeding programs. This valuable resource should be maintained and conserved as a strategy to guarantee the sustainability of coffee production. Core Ideas: This is a groundbreaking study of half‐sib families from old seminal crops.Old seminal matrices are valuable sources of Coffea canephora genetic resources.The characterization, study, and preservation of old seminal matricies are fundamental for breeding of coffee.Divergent families were identified with adequate initial vegetative development. [ABSTRACT FROM AUTHOR]

A diagrammatic scale with five levels (0, 0.1 - 2.0, 2.0 - 6.0, 6.0 - 10, and 10 - 14) was developed and evaluated to measure the symptoms of heat injury in a coffee seedling canopy. The scale was constructed to increase assessment efficiency and align the estimations more closely with the actual values. Two assessments with the diagrammatic scale and one without were conducted with an interval of seven days. The evaluators using the proposed scale presented estimates with better levels of precision, accuracy, reproducibility, and repeatability than those using a conventional method. The proposed diagrammatic scale was shown to provide a reliable estimate for assessing the symptoms of heat injury on the canopy of in Coffea arabica L. seedlings. Therefore, it is possible to standardize heat injury evaluation methods using this diagrammatic scale, allowing for data comparisons with different cultivars. [ABSTRACT FROM AUTHOR]

Coffee leaf rust (CLR) is the most important disease in coffee and is caused by Hemileia vastatrix. The use of a diagrammatic scale helps people more effectively evaluate rust severity and improves disease measurement by evaluators. Our goal was to develop a new scale with colored pictures and seven disease levels (0; 0.1–1.0; 1.1–2.0; 2.1–5.0; 5.1–10.0; 10.1–25.0; >25.0%) and then compare the severity results of CLR on arabica coffee leaves with those based on three other scales. Three evaluations were performed by ten different evaluators. The first assessment was performed without a scale. On the same day, raters performed four assessments with each of the four diagrammatic scales. The third evaluation was performed at seven-day intervals. We analyzed the statistics with linear regression and Lin's concordance correlation. The evaluators using the proposed scale improved the precision, accuracy and reproducibility of the evaluations and reduced residual distribution when compared to the evaluators who did not use the proposed diagrammatic scale or who used the other scales. Overall, the proposed diagrammatic scale is a tool that can assist users in producing a disease estimate close to the real value of CLR on arabica coffee leaves. [ABSTRACT FROM AUTHOR]

Handler and consumer safety are the critical risks associated with conventional chemical preservatives and disinfectants used in the food industry. Alternative nature‐based substances have been explored, obtained and methods for their extraction and isolation developed. Antimicrobial properties of these substances have been mostly targeted for use as food preservatives. However, recent researches indicate their prospective use as surface cleaners, disinfectants for raw produces and process surfaces and biofilm inhibitors. Their activities can be enhanced by several folds using modern technologies like microencapsulation, fragmentation, conjugation, immobilization, nanoemulsion, and coupling with natural detergents. They can act as active agents in antimicrobial films, coatings, and food packages. Critical compilation of reported researches on these is necessary. Latest developments and trends in the use of nature‐based substances as futuristic disinfectants and preservatives for food industry have been reviewed here. Their synergistic effects with novel technologies for implementable hurdle‐technology concepts have been also discussed. Novelty impact statement: Natural substances that have antimicrobial properties and safe for human use are the commercial disinfectants of tomorrow. In this article, we are expressing this futuristic view based on the current trends in researches on nature‐derived cleansing and disinfecting substances and technologies for their maximum efficacy. The information generated is expected to support cross‐sectional achievement of multiple major SDGs of UN 2030 Agenda relating to ensuring safe food for the world community. [ABSTRACT FROM AUTHOR]

Fungi are widely disseminated in the environment and are major food contaminants, colonizing plant tissues throughout the production chain, from preharvest to postharvest, causing diseases. As a result, grain development and seed germination are affected, reducing grain quality and nutritional value. Some fungal species can also produce mycotoxins, toxic secondary metabolites for vertebrate animals. Natural compounds, such as essential oils, have been used to control fungal diseases in cereal grains due to their antimicrobial activity that may inhibit fungal growth. These compounds have been associated with reduced mycotoxin contamination, primarily related to reducing toxin production by toxigenic fungi. However, little is known about the mechanisms of action of these compounds against mycotoxigenic fungi. In this review, we address important information on the mechanisms of action of essential oils and their antifungal and antimycotoxigenic properties, recent technological strategies for food industry applications, and the potential toxicity of essential oils., (© 2023 Institute of Food Technologists®.)

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Austropuccinia psidii Winter, causal agent of myrtle rust, is one of the main pathogens in Eucalyptus plantations in Brazil. We investigated the effects of the pathogen on wood yield and light use efficiency (LUE) in a Eucalyptus grandis x Eucalyptus urophylla clone in a field trial at the end of a five‐year rotation. The study comprised two treatments that are commonly adopted by managers. One treatment with curative fungicide spray (Triadimenol 250 g l−1) seven months after planting and another with five preventive sprays of the same fungicide, from the 1st to 7th month age of saplings. At 5 years old, the control plots attained a mean annual increment of 35 m³ ha−1 yr−1, the curative and preventive treatments were 39 and 47 m³ ha−1 yr−1 (11% and 34% higher, respectively). LUE was also higher when fungicides were applied, 8% and 26% higher in curative and preventive treatments (1.06 and 1.24 g MJ−1) compared with the control plots (0.98 g MJ−1). To confirm the negative effect of rust at a larger scale, we tracked 102 inventory plots (from 1,234 ha) from 2 to 6 years old with the same clone, half infected and half with rust corrective control. Growth difference decreased with time, from an average of 41% at age 2%–5% at age 6. These results highlight the importance of managing myrtle rust in Eucalyptus plantations by selecting a disease‐tolerant genotype or adopting other strategies for disease control. [ABSTRACT FROM AUTHOR]

Amongst the fungi that cause damage to common bean (Phaseolus vulgaris) and are disseminated by seeds, Colletotrichum lindemuthianum stands out. This fungus causes anthracnose in common bean plants. The use of natural compounds, for example essential oils (EO), is a viable and safer option than chemicals to manage this disease. According to the results of the in vitro assay, we observed complete inhibition of the growth of C. lindemuthianum with the use of Cinnamomum cassia EO and its major component (E)‐cinnamaldehyde, presenting MIC of 125 µg/ml, whilst the commercial fungicide presented MIC of 30.6 µg/ml. In addition in vivo assay, where seeds naturally infected with C. lindemuthianum were treated with the EO and the substance in a solution with commercial soybean oil, we observed reducing the incidence of anthracnose over the days evaluated, as well as for the commercial fungicide used (thiophanate‐methyl). In addition, the treatments did not affect germination and initial seed vigour. This is the first study to demonstrate the efficacy of Ci. cassia essential oil and (E)‐cinnamaldehyde on the control of C. lindemuthianum through the treatment of common bean seeds. [ABSTRACT FROM AUTHOR]

In this work, we studied the direct and indirect plant protection effects of an Artemisia absinthium essential oil (AEO) on tomato seedlings against Fusarium oxysporum sp. oxysporum radicis lycopersici (Fol). AEO exhibited a toxic effect in vitro against Fol. Additionally, tomato seedlings germinated from seeds pretreated with AEO and grown hydroponically were protected against Fol. Plant disease symptoms, including, water and fresh weight loss, tissue necrosis, and chlorosis were less pronounced in AEO-treated seedlings. AEO also contributed to plant defenses by increasing callose deposition and the production of reactive oxygen species (ROS) on seed surfaces without affecting seed germination or plant development. The essential oil seed coating also primed a durable tomato seedling defense against the fungus at later stages of plant development. RNA-seq and metabolomic analysis performed on seedlings after 12 days showed that the AEO treatment on seeds induced transcriptomic and metabolic changes. The metabolomic analysis showed an induction of vanillic acid, coumarin, lycopene, oleamide, and an unknown metabolite of m/z 529 in the presence of Fol. The StNRPD2 gene, the second largest component of RNA polymerases IV and V directly involved in de novo cytosine methylation by RNA-directed DNA methylation (RdDM), was highly induced in the presence of AEO. The host methionine cycle (MTC) controlling trans-methylation reactions, was also altered by AEO through the high induction of S-adenosyl methionine transferases (SAMts). Our results suggest that AEO treatment could induce de novo epigenetic changes in tomato, modulating the speed and extent of its immune response to Fol. The EO-seed coating could be a new strategy to prime durable tomato resistance, compatible with other environmentally friendly biopesticides. [ABSTRACT FROM AUTHOR]

Indian cedar (Acrocarpus fraxinifolius) is a wood species that occurs naturally in India, Myanmar (Burma) and Bangladesh, and has a high commercial value, with characteristics like mahogany and native cedars. The planting of Indian cedar has been undertaken in Brazil, but there is little information available regarding the characterization of the species. Therefore, considering its timber potential and its possibility of development in the country, the present work aimed to evaluate the physical, chemical, and mechanical properties of 9-year-old Indian cedar wood, planted in the southern region of Brazil. A low specific mass (502 kg/m³), low average dimensional stability (anisotropy coefficient of 2,09 %) was observed, in addition to the low content of extractives (1,94 %). From the mechanical characterization, an average value for the elastic modulus of 8963 MPa was obtained, and for the compressive strength parallel to the grain the average and characteristic values were 32,14 MPa and 21,46 MPa, respectively. This indicates that this wood belongs to resistance class C20 (dicotyledons). The results obtained classify the wood for use in light, external, or internal civil construction [ABSTRACT FROM AUTHOR]

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Over the past decades, advances in plant biotechnology have allowed the development of genetically modified maize varieties that have significantly impacted agricultural management and improved the grain yield worldwide. To date, genetically modified varieties represent 30% of the world's maize cultivated area and incorporate traits such as herbicide, insect and disease resistance, abiotic stress tolerance, high yield, and improved nutritional quality. Maize transformation, which is a prerequisite for genetically modified maize development, is no longer a major bottleneck. Protocols using morphogenic regulators have evolved significantly towards increasing transformation frequency and genotype independence. Emerging technologies using either stable or transient expression and tissue culture-independent methods, such as direct genome editing using RNA-guided endonuclease system as an in vivo desired-target mutator, simultaneous double haploid production and editing/haploid-inducer-mediated genome editing, and pollen transformation, are expected to lead significant progress in maize biotechnology. This review summarises the significant advances in maize transformation protocols, technologies, and applications and discusses the current status, including a pipeline for trait development and regulatory issues related to current and future genetically modified and genetically edited maize varieties. [ABSTRACT FROM AUTHOR]

Summary: Pratylenchus thornei and P. neglectus attack common bean and cause economic yield losses throughout cultivated areas in Turkey. The most effective management strategy for the P. thornei and P. neglectus infections is crop rotation with non-host crops and breeding resistant/tolerant varieties. However, parent bean genotypes immune to P. thornei and P. neglectus are not available for breeding programmes; thus, resistant varieties are commonly incorporated as parents. In the present research, a total of 36 common bean varieties were tested in a growth room for their host response to these two nematode pests. The reproduction factor and the population density of both nematode species were calculated. All tested bean varieties showed varying levels of resistance and susceptibility to P. thornei and P. neglectus. Among the dry bean varieties, nine were found to be resistant to P. thornei and three to P. neglectus , with three varieties ('Kantar-05', 'Önceler-98' and 'Karacasehir-90') resistant to both species. Among fresh bean varieties, ten were found to be resistant to P. thornei and four to P. neglectus , with four varieties ('Helda', 'Gina', 'Gelincik' and 'Bourgondia') resistant to both species. The resistant common bean varieties identified in this study are a valuable untapped genetic pool that will offer improved resistance levels to P. thornei and P. neglectus , especially 'Gina' and 'Önceler-98', which seem to possess a great source of resistance to P. thornei and P. neglectus , respectively, and can be used in breeding programmes in the near future. [ABSTRACT FROM AUTHOR]

Maize productivity is threatened by global climate change. Climate change scenarios suggest that north‐western (NW) Europe will get warmer and drier during the main crop‐growing period. In general, more northerly regions will benefit, whereas more southerly regions will suffer suboptimal rain‐fed farming conditions. In these latter regions in particular, the resulting probable lower realized on‐farm maize grain and biomass yields must be safeguarded. Breeding for resistance against already existing and emerging diseases and insect pests is one component to achieve yield stability across years. Durable multiple‐disease resistance will become especially crucial. Herein, we focus on disease resistance breeding approaches in maize, especially related to northern corn leaf blight and Fusarium ear rots, although virus and bacterial diseases will become more important as well. Continuous adjustments of disease resistance breeding strategies will be required. Insect pest resistance breeding must be improved considerably, as in a warmer world insects will thrive, probably causing detrimental direct (feeding, sucking, etc.) and indirect (vectors of pathogens, feeding wounds creating gateways for many pathogens, passive transport of inoculum across maize plants) effects. Four case studies on insects that are already prevalent in NW Europe or may be expected in the near future are covered in this review. Maize cultivars need to combine both durable multiple‐disease and multiple‐insect resistance, although the implementation of many different effective resistance resources in breeding programmes will be challenging, particularly if trade‐offs among breeding goals appear. [ABSTRACT FROM AUTHOR]

Propolis is produced by honey bees from a series of resinous, gummy and balsamic substances collected from the leaf buds of different tree species and mixed with their secretions. It is used as a sealant and antiseptic in the hive. Because of its antimicrobial properties, propolis has become a popular alternative medicine or food for health protection and disease prevention. The presence of a large number of flavonoids, aromatic acids and phenolic compounds has been suggested to be responsible for most biological and pharmacological activities of propolis. This review aims to provide a critical analysis of the different studies which evaluate the activity of propolis against fungi and to identify the chemical components responsible for such activity. The discussion of the methodological approaches used and the issued results is a key point of this review to highlight knowledge gaps. This review will first describe the chemical composition of the propolis and the factors of variability including geographical and botanical origins and then examine its antifungal activities with a focus against phytopathogenic fungi. Finally, it will discuss the main components responsible for such activities and their mechanism of action. [ABSTRACT FROM AUTHOR]

Background: The role of fungi in cocoa crops is mainly associated with plant diseases and contamination of harvest with unwanted metabolites such as mycotoxins that can reach the final consumer. However, in recent years there has been interest in discovering other existing interactions in the environment that may be beneficial, such as antagonism, commensalism, and the production of specific enzymes, among others. Scope and approach: This review summarizes the different fungi species involved in cocoa production and the cocoa supply chain. In particular, it examines the presence of fungal species during cultivation, harvest, fermentation, drying, and storage, emphasizing the factors that possibly influence their prevalence in the different stages of production and the health risks associated with the production of mycotoxins in the light of recent literature. Key findings and conclusion: Fungi associated with the cocoa production chain have many different roles. They have evolved in a varied range of ecosystems in close association with plants and various habitats, affecting nearly all the cocoa chain steps. Reports of the isolation of 60 genera of fungi were found, of which only 19 were involved in several stages. Although endophytic fungi can help control some diseases caused by pathogenic fungi, climate change, with increased rain and temperatures, together with intensified exchanges, can favour most of these fungal infections, and the presence of highly aggressive new fungal genotypes increasing the concern of mycotoxin production. For this reason, mitigation strategies need to be determined to prevent the spread of disease-causing fungi and preserve beneficial ones. [ABSTRACT FROM AUTHOR]