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BACKGROUND: Plant defense elicitors are valuable tools in sustainable agriculture, providing an environmentally friendly and effective means of enhancing plant defense and promoting plant health. Fusarium head blight (FHB) is one of the most important fungal diseases of cereal crops worldwide. The PSP1 is a novel biopesticide formulated based on an elicitor, the extracellular protein AsES, from the fungus Sarocladium strictum. The present work aimed to evaluate the effectiveness of PSP1 in controlling FHB under field conditions. Experiments were conducted during three consecutive growing seasons (2019, 2020, and 2021). Three biostimulant treatments were tested in different physiological stages (from late tillering to heading stage), and FHB inoculations were performed at anthesis. Disease parameters, seed parameters, grain yield, and grain quality parameters were evaluated. RESULTS: Depending on the year and the genotype, reductions in disease incidence (up to 11%) and disease severity (up to 5%) were reported, although these differences could not be attributed to the use of the PSP1 biostimulant. Occasional improvements in seed parameters and grain quality were observed, suggesting that early treatments could work better than late treatments, probably due to early activation/priming of defense response mechanisms. However, more studies are deemed necessary. CONCLUSION: The use of PSP1 biostimulant in commercial wheat crops could be a biological alternative or complement to traditional chemical fungicides to manage FHB. The reduced environmental impact and the potential benefits in grain yield and quality are other reasons that can generate new adherents of this technology in worldwide agriculture systems in the coming years. © 2024 Society of Chemical Industry.

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Maize is one of the most important crops worldwide, being affected by several fungal species under field conditions. The study of plant-pathogen interaction plays a key role because fungal diseases are responsible for reducing grain yield and quality by increasing mycotoxin production. Thus, the present work aimed to evaluate the interaction of F. graminearum and F. verticillioides and mycotoxin production under field conditions along different physiological stages. During the 2019/2020 and 2020/2021 growing seasons, twelve maize genotypes were inoculated at the flowering stage (silking). Four treatments were applied using one isolate of each species: (i) F. graminearum; (ii) F. verticillioides; (iii) a combined inoculum (F. graminearum + F. verticillioides); (iv) and control treatment. Fungal diversity, disease evaluation, and mycotoxin contamination were evaluated at three different physiological stages: T1 (from R2 to R4), T2 (from R4 to R6), and T3 (at harvest time). A total of 15,907 Fusarium isolates were obtained. The results showed a predominance of F. verticillioides over F. graminearum in both years evaluated, reporting an increase in the occurrence of this species at late stages. Regarding mycotoxin contamination, no evidence was found supporting antagonism or synergism regarding isolates of both species used as inoculum under field conditions. The results reported in the present manuscript point out a major influence of climatic conditions on F. verticillioides predominance over F. graminearum, mainly during the late physiological stages. Furthermore, no clear relationship between mycotoxin concentration and physiological stages was established, suggesting that other grain factors, such as water activity and pH, could modulate mycotoxin production and accumulation under field conditions.

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BACKGROUND: Barley is one of the most sown crops in the world, with multiple uses such as human consumption, animal feed and for the malting industry. This crop is affected by different diseases, such as Fusarium Head Blight (FHB), that causes losses in yield and quality. In the last years F. graminearum and F. poae were two of the most frequently isolated species in barley grains, so the aim of this study was to evaluate the interaction between these Fusarium species and the effects on disease parameters, grain quality and mycotoxin contamination on five barley genotypes under field conditions. RESULTS: Statistical differences between Fusarium treatments for some parameters depending mainly on the year/genotype were found. The results showed that the germination process was affected by both Fusarium species. As to grain quality and the different hordein fractions, it was observed that F. graminearum affects preferentially D and C-hordeins. Different concentrations of nivalenol, deoxynivalenol and their acetylated derivatives (3-acetyl deoxynivalenol (3-ADON), 15-acetyl deoxynivalenol (15-ADON)) were detected. CONCLUSIONS: In the present work, no evidence of synergism between F. graminearum and F. poae were found regarding disease parameters and mycotoxin contamination. However, at least in the years with favorable climatic conditions to FHB development and depending on the barley genotype, a continuous monitoring is deemed necessary to prevent the negative impact on protein composition and germinative parameters © 2020 Society of Chemical Industry.

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BACKGROUND: Wheat is the most important winter crop in the world, being affected by the presence of fungal, mainly those belonging to the Fusarium genus. Fusarium head blight (FHB) is a serious disease that causes important economic damage and quantitative/qualitative losses, with Fusarium graminearum and Fusarium poae being two of the most isolated species worldwide. The present study aimed to evaluate the interaction between F. graminearum and F. poae and the effects on disease parameters, grain quality and mycotoxin contamination on five wheat genotypes under field conditions during three growing seasons. RESULTS: Statistical differences between Fusarium treatments were found for disease parameters, grain quality and mycotoxin contamination during the 2014/2015 growing season. High values of incidence (58.00 ± 8.00%), severity (6.28 ± 1.51%) and FHB index (4.72 ± 1.35) were observed for F. graminearum + F. poae treatment. Regarding grain quality, the results showed that the degradation of different protein fractions depends on each Fusarium species: glutenins were degraded preferably by F. graminearum (-70.82%), gliadins were degraded preferably by F. poae (-29.42%), whereas both protein fractions were degraded when both Fusarium species were present (-60.91% and -16.51%, respectively). Significant differences were observed for mycotoxin contamination between genotypes, with Proteo being the most affected (DON = 12.01 ± 3.67 µg g-1 ). In addition, we report that 3-ADON predominated over 15-ADON in the three seasons evaluated. CONCLUSION: Variations in plant-pathogen interaction (Fusarium-wheat pathosystem) should be considered at least in years with favorable climatic conditions for FHB development, as a result of the potential impact of this disease on grain quality and mycotoxin contamination. © 2019 Society of Chemical Industry.

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Two of the most common species of toxin-producing Fusarium contaminating small cereal grains are Fusarium graminearum and F. poae; with both elaborating diverse toxins, especially deoxynivalenol (DON) and nivalenol (NIV), respectively. The objective of our work during the 2012-2014 growing seasons was to screen crops for the most commonly isolated Fusarium species and to quantify DON and NIV toxins in natural malting-barley samples from different producing areas of Argentina. We identified 1180 Fusarium isolates in the 119 samples analyzed, with 51.2% being F. graminearum, 26.2% F. poae and 22.6% other species. We found high concentrations of mycotoxins, at maximum values of 12 µg/g of DON and 7.71 µg/g of NIV. Of the samples, 23% exhibited DON at an average of 2.36 µg/g, with 44% exceeding the maximum limits (average of 5.24 µg/g); 29% contained NIV at an average of 2.36 µg/g; 7% contained both DON and NIV; and 55% were without DON or NIV. Finally, we report the mycotoxin contamination of the grain samples produced by F. graminearum and F. poae, those being the most frequent Fusarium species present. We identified the main Fusarium species affecting natural malting-barley grains in Argentina and documented the presence of many samples with elevated concentrations of DON and NIV. To our knowledge, the investigation reported here was the first to quantify the contamination by Fusarium and its toxins in natural samples of malting barley in Argentina.

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RESUMO Confiável quantificação da demanda bioquímica de oxigênio exercida (DBO exercida) poderá ser obtida com incubação das amostras sob temperaturas diferentes, desde que o valor da demanda bioquímica de oxigênio última (DBOU) não seja alterado nessas condições. Alguns autores têm relatado aumento no valor da DBOU com a elevação da temperatura de incubação das amostras, o que pode ser decorrente da ocorrência da nitrificação, da aclimatação diferenciada ou do mau ajuste dos modelos de progressão da demanda bioquímica carbonácea de oxigênio (DBO exercida). Neste estudo, objetivou-se avaliar o efeito da temperatura sobre a progressão da DBO exercida e o valor da DBOu em amostras de esgoto doméstico bruto, avaliando-se qual modelo melhor se ajusta aos dados obtidos. Os resultados indicaram pequena influência da temperatura de incubação das amostras nos valores da DBOU do esgoto sanitário e que os modelos de primeira e segunda ordens descreveram adequadamente a progressão da DBO exercida.

ABSTRACT Reliable quantification of biochemical oxygen demand exerted (exerted BOD) can be obtained by incubating samples at different temperatures, since the amount of ultimate biochemical oxygen demand (UBOD) does not change in these conditions. Some authors have found increased UBOD values with rise in temperature of incubating samples, which could be due to the occurrence of nitrification, the acclimatization or the inadequacy of modeling of carbonaceous oxygen demand (exerted BOD) progression. This study aimed to evaluate the effect of temperature on the progression of exerted BOD and UBOD values in samples of raw domestic sewage, checking which model best fits the data. The results indicated low influence of incubating sewage samples temperature on UBOD values, being that both models, first and second order, described properly the exerted BOD progression.

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One of the most important diseases in cereal crops is Fusarium head blight, being Fusarium graminearum the main etiological agent. This fungus has the ability to produce a wide spectrum and quantity of toxins, especially deoxynivalenol (DON). During the last crop season (2012-2013) the climatic conditions favored Fusarium colonization. The objective of this work was to determine the presence of this fungus as well as the DON content in 50 wheat grain samples. Our results showed that 80% of the samples were contaminated with Fusarium graminearum. Twenty four percent (24%) of the samples contained ≥ 1µg/g DON, 26% ranged from 0,5 and 0,99µg/g, and the remaining 50% had values lower than 0,5µg/g. Correlation was found between the presence of Fusarium graminearum and DON. It is necessary to establish DON limit values in wheat grains for human consumption.

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La fusariosis es una de las enfermedades más importantes de los cereales, Fusarium graminearum es su principal agente etiológico. Este hongo posee la capacidad de producir distintos tipos y niveles de toxinas, en especial deoxinivalenol (DON). En la campaña 2012-2013 se dieron condiciones ambientales predisponentes para el desarrollo de esta enfermedad. El objetivo de este trabajo fue evaluar la presencia del hongo y el contenido de DON en 50 muestras de trigo. Los resultados demostraron la presencia de Fusarium graminearum en el 80 % de las muestras analizadas. El 24 % de las muestras presentó valores de DON ≥ 1µg/g, el 26 % varió entre 0,5 y 0,99µg/g, mientras que el 50 % restante mostró valores inferiores a 0,5µg/g. Se observó correlación entre la presencia de Fusarium graminearum y de DON. Es necesario establecer valores límites de DON en granos de trigo destinados al consumo humano

One of the most important diseases in cereal crops is Fusarium head blight, being Fusarium graminearum the main etiological agent. This fungus has the ability to produce a wide spectrum and quantity of toxins, especially deoxynivalenol (DON). During the last crop season (2012-2013) the climatic conditions favored Fusarium colonization. The objective of this work was to determine the presence of this fungus as well as the DON content in 50 wheat grain samples. Our results showed that 80% of the samples were contaminated with Fusarium graminearum. Twenty four percent (24%) of the samples contained ≥ 1µg/g DON, 26% ranged from 0,5 and 0,99µg/g, and the remaining 50% had values lower than 0,5µg/g. Correlation was found between the presence of Fusarium graminearum and DON. It is necessary to establish DON limit values in wheat grains for human consumption

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One of the most important diseases in cereal crops is Fusarium head blight, being Fusarium graminearum the main etiological agent. This fungus has the ability to produce a wide spectrum and quantity of toxins, especially deoxynivalenol (DON). During the last crop season (2012-2013) the climatic conditions favored Fusarium colonization. The objective of this work was to determine the presence of this fungus as well as the DON content in 50 wheat grain samples. Our results showed that 80

of the samples were contaminated with Fusarium graminearum. Twenty four percent (24

) of the samples contained  1Ag/g DON, 26

ranged from 0,5 and 0,99Ag/g, and the remaining 50

had values lower than 0,5Ag/g. Correlation was found between the presence of Fusarium graminearum and DON. It is necessary to establish DON limit values in wheat grains for human consumption.

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Gas exchanges influence growth, development and production of crops and are associated with the plant water conditions, which can be dependent on the soil and climate conditions. The present study aimed at evaluating transpiration, photosynthesis, stomatal conductance, internal CO2 concentration and foliar temperature of 'Tommy Atkins'mango trees under different irrigation treatments in the semiarid region of Bahia (BA, Brazil). The experimental design was a randomized block with five treatments and six replicates: 1, irrigation providing 100 % of crop evapotranspiration (ETc) in phases: I (early blooming to early fruit expansion), II (early expansion to early physiologic ripening) and in phase III (physiologic ripening of fruits); 2, regulated deficit irrigation (RDI) with 50 % of ETc in phase I; 3, RDI with 50 % ETc in phase II; 4, RDI with 50 % ETc in phase III; 5, no irrigation. Total or partial soil water deficit caused reduction in photosynthetic rate, transpiration and stomatal conductance of 'Tommy Atkins' leaves. Partial soil water deficit does not cause significant alterations in internal CO2 concentration or in leaf temperature of 'Tommy Atkins' mango trees.

As trocas gasosas influenciam o crescimento, o desenvolvimento e a produção das culturas e estão relacionados às condições hídricas da planta que podem ser uma resposta ao estado hídrico do solo e às condições de clima. Objetivou-se com este trabalho avaliar a transpiração, fotossíntese, condutância estomática, concentração interna de CO2 e temperatura foliar da mangueira 'Tommy Atkins' sob diferentes regimes de irrigação no semiárido baiano. O delineamento experimental foi em blocos casualizados com cinco tratamentos e seis repetições: 1 ­ Irrigação suprindo 100% da ETc nas fases: I (início da floração a início da expansão dos frutos), II (inicio da expansão até inicio da maturação fisiológica) e na fase III (maturação fisiológica dos frutos); 2 ­ RDI com 50% da ETc na fase I; 3 ­ RDI com 50% ETc na fase II; 4 ­ RDI com 50% ETc na fase III; 5 ­ Sem irrigação. O déficit hídrico total ou parcial no solo ocasionou redução na taxa fotossintética, na transpiração e na condutância estomática das folhas da mangueira 'Tommy Atkins'. O déficit hídrico parcial no solo não ocasiona alterações significativas na concentração interna de CO2 e na temperatura foliar da mangueira 'Tommy Atkins'.

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