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Solutions based on image analysis are a growing trend towards improving the quality of forest seeds. This study aimed to associate the information obtained through the processing of radiographic images with the physiological potential of Anadenanthera peregrina seeds. Ten seed lots from different mother trees were submitted to automated X-ray analysis to obtain variables related to seed morphology and tissue integrity. Then, the seeds were evaluated for their physiological potential through the variables germination, normal seedlings, germination speed index (GSI), seedling length, uniformity index, and vigor index. The results showed that there was a relationship between the variables obtained with the X-ray analysis and those of the physiological potential of the seeds. Most of the lots with low physiological potential had lower tissue density, circularity, and a higher positive skewness value. The X-ray technique can be considered valid to establish a relationship between the physical and physiological quality of seeds, however, it seems to be more efficient to identify seeds with low physiological potential.

Saflufenacil is a herbicide recommended for use in the main agricultural crops in Brazil to control eudicotyledonous weeds. However, the application of saflufenacil has been carried out without previous knowledge of this herbicide interactions with soil colloids, which may increase environmental contamination risks. In this study, the leaching of saflufenacil in soil samples was estimated with different organic matter contents. Therefore, PVC columns were filled with samples of Xanthic Ferralsol (XF) and Ferralsol (F), with different physical and chemical attributes. Twelve hours after herbicide (70 g i.a. ha-1) application, the PVC columns were subjected to a rainfall of 60 mm. For the evaluation of saflufenacil leaching, the columns were sectioned in ten parts with 5-cm each. Saflufenacil leached up to 50 and 40 cm deep in the samples, with the lowest contents of organic matter of XF and F, respectively. The increase in organic matter content of Ferralsol and Xanthic Ferralsol samples reduced saflufenacil leaching and the symptoms of intoxication in the indicator species. There was an inverse relation between the content of organic matter and the leaching of the herbicide in both soils studied. It was observed that the application of saflufenacil in soils with low organic matter contents may represent a significant environmental contamination risk of soils and watercourses. Saflufenacil é um herbicida recomendado para uso nas principais culturas agrícolas no Brasil para o controle de plantas daninhas eudicotiledôneas. No entanto, o saflufenacil tem sido aplicado sem o conhecimento prévio desse herbicida com os coloides do solo, o que pode aumentar o risco de contaminação ambiental. Por essa razão, o objetivo deste trabalho foi estimar a lixiviação do saflufenacil em amostras de solos com diferentes teores de matéria orgânica. Para isso, colunas de PVC foram preenchidas com amostras de Latossolo Amarelo e Latossolo Vermelho-Amarelo com diferentes atributos físicos e químicos. Após a aplicação do herbicida, as colunas de PVC foram submetidas à 60 mm de chuva simulada. Para a avaliação da lixiviação do saflufenacil, as colunas foram seccionadas a cada 5 cm. O saflufenacil lixiviou até a profundidade de 50 e 40 cm das amostras de solo com o menor teor de matéria orgânica, do Latossolo Amarelo e Latossolo Vermelho-Amarelo, respectivamente. O aumento do teor de matéria orgânica em amostras de ambos os solos reduziu a lixiviação do saflufenacil e os sintomas de intoxicação da espécie indicadora. Observa-se que houve uma relação inversa entre o teor de matéria orgânica e a lixiviação do herbicida em ambos os solos estudados. Conclui-se que a aplicação do saflufenacil em solos com baixo teor de matéria orgânica pode representar um significativo risco de contaminação ambiental de solos e cursos d’água.

New computer vision solutions combined with artificial intelligence algorithms can help recognize patterns in biological images, reducing subjectivity and optimizing the analysis process. The aim of this study was to propose an approach based on interactive and traditional machine learning methods to classify soybean seeds and seedlings according to their appearance and physiological potential. In addition, we correlated the appearance of seeds to their physiological performance. Images of soybean seeds and seedlings were used to develop models using low-cost approaches and free-access software. The models developed showed high performance, with overall accuracy reaching 0.94 for seeds and seedling classification. The high precision of the models that were developed based on interactive and traditional machine learning demonstrated that the method can easily be used to classify soybean seeds according to their appearance, as well as to classify soybean seedling vigor quickly and non-subjectively. The appearance of soybean seeds is strongly correlated with their physiological performance.

The aim of this study was to evaluate the resistance of Botrytis cinerea to the fungicides currently used for its control in Brazil. Isolates of the fungus were collected from different strawberry-producing fields in the states of Espírito Santo, Minas Gerais, and São Paulo, Brazil. First, a total of 183 isolates were identified at the species level using specific primers for the glyceraldehyde-3-phosphate dehydrogenase (G3PDH) gene. The isolates were grown on potato dextrose agar (PDA) containing the fungicides procymidone, iprodione, and thiophanate-methyl in different concentrations: 0.0 (control), 0.1; 1.0; 10.0; 100.0 and 1,000.0 μg∙mL−1. The percentage of mycelial growth inhibition was used to determine the effective concentration of the fungicide that was able to inhibit colony growth by 50% (EC50). Approximately 25.7% of the isolates were resistant to iprodione, 53.0% were resistant to procymidone, and 93.0% were resistant to thiophanate-methyl. Moreover, crossresistance and multiple resistance were verified, with 19.7% of the isolates showing resistance to 3 fungicides simultaneously. This finding explains the ineffectiveness of fungicides application to control gray mold in strawberry fields in Brazil and highlights the need for new strategies to manage this disease in the culture.

EnglishThe application of desiccant herbicides in the bean crop is fundamental in the production of quality seeds, since it anticipates the harvesting season, which makes it possible to obtain seeds in the period of physiological maturation, when they are reported with maximum accumulation of dry matter, high vigor levels and germination percentage. However, there is little information about the ideal application time of these products to obtain beans of high physiological quality. Therefore, the objective of this study was to evaluate the physiological quality of bean seeds after application of desiccant herbicides at different times in preharvest. The experimental design was a randomized complete block design in a 2x3+1 factorial scheme, with four replications. Desiccant herbicides paraquat (400g ha-1) and paraquat + diuron (200 + 400g ha-1) were applied in three phenological stages (R8, R8/R9 and R9), plus one control (without herbicide application). Yield (Kg ha-1), mass of one thousand seeds (g), germination (%) and seed vigor were evaluated through tests of accelerated aging, electrical conductivity and primary root length. Application of paraquat molecule at the R8 stage and the paraquat + diuron mixture at the R8/R9 stage reduced the viability and vigor of the bean seeds, and compromised yield. Applications of the paraquat herbicide at the R8/R9 and R9 stages or of the mixture (paraquat + diuron) at the R9 stage preserved the physiological quality of the seeds without;however, affecting yield. portuguesA aplicacao de herbicidas dessecantes na cultura do feijoeiro e fundamental na producao de sementes de qualidade porque antecipa a epoca de colheita, o que possibilita a obtencao de sementes no periodo de maturacao fisiologica, quando se encontram com maximo acumulo de materia seca, elevados niveis de vigor e alta porcentagem de germinacao. Todavia, sao escassas as informacoes acerca da epoca ideal de aplicacao desses produtos na obtencao de sementes de feijao de alta qualidade fisiologica. Por essa razao, objetivou-se avaliar a qualidade fisiologica de sementes de feijao apos aplicacoes de herbicidas dessecantes em diferentes epocas na pre-colheita. O delineamento experimental utilizado foi o de blocos casualizados dispostos em esquema fatorial 2x3+1, com quatro repeticoes. A aplicacao dos herbicidas dessecantes paraquat (400g ha-1) e paraquat + diuron (200+400g ha-1) foi realizada em tres estadios fenologicos (R8, R8/R9 e R9), mais uma testemunha (sem aplicacao do herbicida). Avaliou-se a produtividade (Kg ha-1), a massa de mil sementes (g), a germinacao (%) e o vigor das sementes por meio dos testes de envelhecimento acelerado, condutividade eletrica e comprimento da raiz primaria. A aplicacao da molecula de paraquat no estadio R8 e da mistura paraquat + diuron no estagio R8/R9 reduziu a viabilidade e o vigor das sementes de feijao, alem disso comprometeu a produtividade. Aplicacoes dos herbicidas paraquat nos estadios R8/R9 e R9 ou da mistura (paraquat + diuron) no estadio R9 preservaram a qualidade fisiologica das sementes, sem, entretanto, afetar a produtividade.

O conhecimento das alterações na comunidade infestante provocado pelo manejo de plantas daninhas é importante para definição de estratégias eficientes para o controle destas. Realizou-se um experimento de campo para avaliar os efeitos do uso de herbicidas em diferentes alturas de barra na dinâmica de plantas daninhas e produtividade do feijoeiro. Adotou-se arranjo fatorial em esquema 3x4+1, constituído pela combinação de três herbicidas (fomesafen, fluazifop-p-butil e sua mistura) e quatro alturas de barras do pulverizador (0,20; 0,30; 0,40 e 0,50 m) e mais a testemunha sem capina. Aos 30 dias após aplicação (DAA) determinou-se os seguintes índices fitossociológicos: frequência relativa, densidade relativa, dominância relativa, índice de valor de importância e índice de similaridade. Aos 60 DAA foi determinada a produtividade. Antes da instalação do experimento foram identificadas 22 espécies em toda área experimental. As espécies Alternanthera tenella, Chelidonium majus, Digitaria horizontalis e Bidens pilosa predominaram na área cultivada em que não houve controle. A redução da altura de barras na aplicação do fomesafen reduziu a importância das espécies eudicotiledôneas. Nas parcelas com aplicação de fomesafen + fluazifop-p-butil o número de infestantes eudicotiledôneas foi superior às demais, com predominância de A. tenella e B. pilosa. No geral, o índice de similaridade entre os diferentes herbicidas e as diferentes alturas de barra foi baixo, o que indica que os tratamentos aplicados resultam em diferentes populações de plantas daninhas. O feijoeiro reduz a diversidade de plantas daninhas e a aplicação de herbicidas altera a infestação destas com consequência no ganho em produtividade.

Automated analysis of seed vigor stands out by allowing greater accuracy, standardization, objectivity, and speed in evaluation of the physiological potential of seed lots. The objective of this study was to evaluate the efficiency of the Vigor-S® system in assessing the physiological quality of common bean seeds compared to the information provided by the traditional vigor tests recommended for this species. Four genotypes of common bean were used, each one represented by four seed lots. Characterization of the physiological potential of the lots was carried out by the following tests: germination, first count of germination, seedling emergence, accelerated aging, and electrical conductivity. The results of these tests were compared with the data obtained from the image analysis technique, specifically the Vigor-S® system, which was used to evaluate seedling growth at two, three, and four days after the beginning of the germination test. Shoot length, primary root length, and seedling length were measured, as well as the growth index, uniformity index, and vigor index were calculated. Computerized analysis of seedling images using the Vigor-S® software is a reliable alternative for evaluation the physiological potential of bean seeds, and it produces information similar to evaluations traditionally used for that purpose. Resumo: A análise automatizada do vigor de sementes tem se destacado por permitir maior precisão, padronização, objetividade e velocidade na avaliação do potencial fisiológico de lotes de sementes. O presente trabalho teve como objetivo avaliar a eficiência do sistema Vigor-S® na determinação do potencial fisiológico de sementes de feijão comum, em comparação às informações fornecidas por testes de vigor recomendados para essa espécie. Foram utilizados quatro genótipos de feijão comum, cada um representado por quatro lotes. A caracterização do potencial fisiológico dos lotes foi realizada por meio dos testes de germinação, primeira contagem de germinação, emergência de plântulas, envelhecimento acelerado e condutividade elétrica. Os resultados desses testes foram comparados com os dados obtidos com o uso da técnica de análise de imagem, por meio do software Vigor-S®, que foi utilizado para avaliar o crescimento das plântulas aos dois, três e quatro dias após o início do teste de germinação, mediante a obtenção de valores de comprimento da parte aérea, raiz primária, plântula, e os índices de crescimento, uniformidade e vigor. A análise computadorizada de imagens de plântulas utilizando o software Vigor-S® é eficiente para a avaliar o potencial fisiológico de sementes de feijão, de forma similar às avaliações tradicionalmente utilizadas para esta finalidade.