Optimized irrigation and fertilization can mitigate negative CO2 impacts on seed yield and vigor of hybrid maize.

Seed yield and vigor of hybrid maize determine the planting, yield, and quality of maize, and consequently affect food, nutrition, and livelihood security; however, the response of seed yield and vigor to climate change is still unclear. We established an optimization-simulation framework consisting of a water­nitrogen crop production function, a seed vigor and a gridded process-based model to optimize irrigation and nitrogen fertilization management, and used it to evaluate seed yield and vigor in major seed production locations of China, the USA, and Mexico. This framework could reflect the influence of water and nitrogen inputs at different stages on seed yield and vigor considering the spatio-temporal variability of climate and soil properties. Projected seed yield and vigor decreased by 5.8-9.0 % without adaptation by the 2050s, due to the 1.3-5.8 % decrease in seed number and seed protein concentration. Seed yield was positively correlated with CO2 and negatively correlated with temperature, while seed vigor depended on the response of components of seed vigor to climatic factors. Under optimized management, the direct positive effects of temperature on seed protein concentration and CO2 on seed number were strengthened, and the direct negative effects of temperature on seed number and CO2 on seed protein concentration were weakened, which mitigated the reductions in both seed yield and vigor. Elevated CO2 was projected to exacerbate the 2.6 % seed vigor reduction and mitigate the 2.9 % seed yield loss without adaptation, while optimized management could increase seed yield by 4.1 % and mitigate the 2.2 % seed vigor reduction in the Hexi Corridor of China, and decrease the seed yield and vigor reduction by 2.4-5.8 % in the USA and Mexico. Optimized management can strengthen the positive and mitigate the negative effects of climate change on irrigated hybrid maize and inform high-yield and high-quality seed production globally.

Ventral Pallidum and Amygdala Cooperate to Restrain Reward Approach under Threat.

Foraging decisions involve assessing potential risks and prioritizing food sources, which can be challenging when confronted with changing and conflicting circumstances. A crucial aspect of this decision-making process is the ability to actively overcome defensive reactions to threats and focus on achieving specific goals. The ventral pallidum (VP) and basolateral amygdala (BLA) are two brain regions that play key roles in regulating behavior motivated by either rewards or threats. However, it is unclear whether these regions are necessary in decision-making processes involving competing motivational drives during conflict. Our aim was to investigate the requirements of the VP and BLA for foraging choices in conflicts involving overcoming defensive responses. Here, we used a novel foraging task and pharmacological techniques to inactivate either the VP or BLA or to disconnect these brain regions before conducting a conflict test in male rats. Our findings showed that BLA is necessary for making risky choices during conflicts, whereas VP is necessary for invigorating the drive to obtain food, regardless of the presence of conflict. Importantly, our research revealed that the connection between VP and BLA is critical in controlling risky food-seeking choices during conflict situations. This study provides a new perspective on the collaborative function of VP and BLA in driving behavior, aimed at achieving goals in the face of dangers.

Moisture content and temperature of storage in peach palm seed conservation / Teor de água e temperatura de armazenamento na conservação de sementes de pupunha

The peach palm (Bactrisgasipaes) is an important alternative for heart-of-palm extraction, showing precocity, rusticity and high tillering. The seeds of this species are considered recalcitrant making storage for long periods and production of seedlings difficulty. This identified a combination of moisture content of peach palm seeds and temperature during storage for longer seed longevity. Seeds with 35% and 45% of moisture content (wet basis - wb) were storage at 20 °C and 25 ºC during 180 days. The evaluations were carried out every 60 days by the germination test, emergence in sand, shoot length, diameter of stem, shoot dry matter, root dry matter and moisture content. It was observed that seeds with moisture content of 45% wb showed better performance during storage. The storage at 20 ºC provides higher seed quality maintenance. Peach palm seeds maintain their viability for 120 days when stored with moisture content of 45% wb at 20 ºC.

A pupunha (Bactris gasipaes) é uma importante alternativa para a extração de palmito, apresentando precocidade, rusticidade e alto grau de perfilhamento. As sementes desta espécie são consideradas recalcitrantes, dificultando o armazenamento por longos períodos e a produção de mudas. Neste trabalho objetivou-se identificar uma combinação de teor de água das sementes de pupunha e temperatura durante o armazenamento para maior longevidade das sementes. Foram utilizadas sementes com teor de água de 35% e 45% (base úmida - bu), armazenadas a 20 °C e 25 ºC por 180 dias. As avaliações foram realizadas a cada 60 dias, por meio do teste de germinação, emergência em areia, comprimento da parte aérea, diâmetro de coleto, massa de matéria seca de parte aérea, massa de matéria seca de raiz das plantas e teor de água das sementes. Observou-se que as sementes com teor de água de 45% tiveram desempenho superior durante o armazenamento. A temperatura de 20 ºC proporciona maior manutenção da qualidade das sementes. Sementes de pupunha mantêm sua viabilidade durante 120 dias, quando armazenadas com teor de água de 45% a 20 ºC.

Performance of 'Gala Select' and 'Fuji Suprema' grafted on Geneva series rootstocks under fallow land and replanting conditions in southern Brazil.

Background: Rootstocks less vigorous are among the most crucial management techniques to modernize fruit cultivation. Replanting with fallow land has become necessary due to a lack of land to establish new orchards. Objective: The aim of this study is to determine the effect of various rootstocks of the American Geneva® series on the yield performance of the apple (Malus domestica Borkh) cultivars 'Gala Select' and 'Fuji Suprema' under replanting conditions in southern Brazil. Methods: After two years of fallow land, the experiments were initiated in 2017 and conducted during the 2018, 2019, 2020, and 2021 growing seasons in Painel and Caxias do Sul municipalities at the Santa Catarina and the Rio Grande do Sul State, respectively. The 'Gala Select' and 'Fuji Suprema' were grafted onto the G.202, G.814, G.210, and G.213 Geneva series rootstocks in a tall spindle training system using a randomized complete block design with four replicates. Principal component analysis (PCA) was used to assess the interrelationship among the variable's vigor, productivity, and fruit quality. Results: The PCA result showed significant differences in vigor, productivity, and fruit quality when the G.210 and G.213 and G.814 and G.213 Geneva series rootstocks were used in combination with Gala Select and Fuji Suprema cultivars, respectively. The PCA analysis clustered all cultivar/rootstock combinations into two groups, based on their vigor and productivity and the yield performance and fruit quality data, that differed significantly among combinations and regions. The 'Gala Select'/G.202 and 'Fuji Suprema'/G.213 combinations were less vigorous than the 'Gala Select'/G.210 and 'Fuji Suprema'/G.814 combinations. However, 'Gala Select'/G.210 (semi-dwarfing) and G.213 (dwarfing) are the combinations with high yield performance, productive efficiency and fruit quality, being more reliable to the producer, and less vigorous, resulting in lower labor costs under replating conditions, with two years of fallow land, from 2018 until 2021 growing seasons.

Does Forced Plant Maturation by Applying Herbicide with Desiccant Action Influence Seed Longevity in Soybean?

Herbicides with desiccant actions may be used to anticipate the harvesting of soybean seeds. This technique aims to minimize the negative influence of biotic and abiotic factors on seed physiological quality at the end of the plant cycle. However, forced seed maturation with the application of herbicides can compromise the acquisition of seed quality components, especially longevity. Thus, the objective of this research was to evaluate the physiological quality of soybean seeds subjected to forced maturation with desiccants. The experiment was performed in a completely randomized design, with a treatment consisting of soybean plants subjected to the application of herbicides with desiccant action at stage R7.3 and another that underwent the natural process of maturation, that is, without herbicide application. The herbicide used was Paraquat. Seed germination, vigor (first germination count, dry mass, seedling length, time to reach 50% germination(t50), emergence index, and emergence speed), and longevity(P50) were evaluated. The herbicides did not affect germination (normal seedlings). However, the acquisition of vigor and longevity, and the preservation of seed vigor during storage were affected. Thus, the results indicate that the application of herbicide with desiccant action interrupts the process of acquisition of seed physiological quality, notably longevity in soybean seeds.

Epigenetic Regulation in Heterosis and Environmental Stress: The Challenge of Producing Hybrid Epigenomes to Face Climate Change.

Epigenetic regulation has the potential to revolutionize plant breeding and improve crop yields by regulating gene expression in plants. DNA methylation and histone modifications are key epigenetic modifications that can impact plant development, stress responses, productivity, and yields. Higher-yielding crops not only generate greater profits for farmers and seed producers, but also require less land, water, fuel, and fertilizer than traditional crops for equivalent yields. The use of heterosis in crops can influence productivity and food quality, but producing hybrids with superior agronomic traits to their parents remains challenging. However, epigenetic markers, such as histone methylation and acetylation, may help select parental and hybrid combinations with better performances than the parental plants. This review assesses the potential applications of epigenetics in crop breeding and improvement, rendering agriculture more efficient, sustainable, and adaptable to changing environmental conditions.

Método de seleção de sementes de milho crioulo para pequenos produtores / Landrace maize seed selection method for small producers

A seleção de sementes com qualidade fisiológicaé fundamental para pequenos agricultores, que selecionam e salvam as sementes para a próxima safra. O objetivo do trabalho foi avaliar a qualidade fisiológica de sementes em três posições na espiga, de duas variedades de milho crioulo. Oexperimento foi realizado no município de Bagé, no ano de 2020, com sementes da safra 2019/2020 na Faculdade IDEAU. Foram utilizadas sementes das variedades Ferrinho e Amarelão, no delineamento inteiramente casualizado, com quatro repetições e os tratamentos foram compostos pela separação das sementes em três posições da espiga: Basal, Intermediária e Apical. Foram realizados os testes de germinação, primeira contagem da germinação, comprimento de plântula e massa seca de plântula. As sementes das posiçõesBasal e Intermediária apresentam germinação entre 94 e 98%, superior a posição Apical. A primeira contagem da germinação e os testes de comprimento e massa seca de plântula mostraram baixo nível de vigor para todos os tratamentos. As sementes das posiçõesBasal e Intermediária das var. de milho crioulo Amarelão e Ferrinho apresentaram maior viabilidade, mostrando que sua seleção, com descarte das sementes Apicais, demonstra potencial como método de seleção para agricultores familiares. Entretanto, independentemente da posição na espiga, as sementes analisadas apresentaram baixo nível de vigor.(AU)

The selection of seeds with physiological quality is essential for smallfarmers, who select and save seeds for the next crop. The objective of this work was to evaluate the physiological quality of seeds in three positions on the ear of two varieties landrace maize. The experiment was carried out in the municipality of Bagé, in the year 2020, with seeds from the 2019/2020 harvest at Faculdade IDEAU. Seeds of the Ferrinho and Amarelão varieties were used, in a completely randomized design, with four replications and the treatments were composed by separating the seeds in three positions of the ear: Basal, Intermediate and Apical. Tests for germination, first germination count, seedling length and seedling dry mass were performed. The seeds of the Basal and Intermediate positions present germination between 94 and 98%, higher than the Apical position. The first germination count and the tests of seedling length and dry mass showed a low level of vigour for all treatments. The seeds of the Basal and Intermediate positions of var. of landrace maize Amarelão and Ferrinho showed higher viability, showing that their selection, with the disposal of Apical seeds, demonstrates potential as selection method for small farmers. However, regardless of the position on the ear, the seeds analyzed showed a low level of vigour.(AU)

Physical and physiological qualities and productivity of corn seeds fertilized with poultry waste / Avaliação das qualidades física e fisiológica e da produtividade de sementes de milho adubado com resíduo avícola

ABSTRACT: This study evaluated the physical and physiological qualities and productivity of corn seeds, a variety UFVM 100 Native, produced in plots fertilized in top dressing with different levels of poultry waste. The experiment was organized in a randomized block design, with six treatments and four repetitions, totaling 24 plots. The treatments consisted of the application of 0.0, 1.5, 3.0, 4.5, 6.0, and 7.5 t/ha of tanned poultry waste. The seeds were subjected to the following evaluations: uniformity test, thousand seed weight, germination, vigor (first germination count, accelerated aging, soilless cold test, percentage, and emergence rate in sand), and productivity. Linear regression models were used to evaluate the effects of different dosages of poultry waste on the variables considered. The quality of seeds was not influenced by the effects of different levels of fertilization. Among the dosages used, 7.5 t/ha is recommended because it provides a greater increase in productivity, which may result in a greater financial return to the producer.

RESUMO: Este trabalho teve como objetivo avaliar as qualidades física e fisiológica, bem como a produtividade das sementes de milho, variedade UFVM 100 Nativo, produzidas em lavouras adubadas com diferentes níveis de resíduo avícola, em cobertura. O experimento foi instalado no delineamento em blocos casualizados, com seis tratamentos e quatro repetições, totalizando 24 parcelas. Os tratamentos consistiram da aplicação de 0,0; 1,5; 3,0; 4,5; 6,0 e 7,5 t/ha de resíduo avícola curtido. As sementes foram submetidas às seguintes avaliações: Teste de uniformidade, peso de mil sementes, germinação, vigor (primeira contagem de germinação, envelhecimento acelerado, teste de frio sem solo, porcentagem e velocidade de emergência em areia) e produtividade. Para avaliar o efeito das diferentes dosagens de resíduo avícola sobre as variáveis consideradas foram utilizados modelos de regressão linear. A qualidade das sementes não foi influenciada pelo efeito dos diferentes níveis de adubação. Dentre as dosagens utilizadas, recomenda-se a de 7,5 t/ha por proporcionar maior aumento da produtividade, o que poderá resultar em maior retorno financeiro ao produtor.

Soybean seeds treated with zinc evaluated by X-ray micro-fluorescence spectroscopy

Zinc (Zn) is a micronutrient considered essential to plants which can be supplied through seed treatment. The treatment of soybean [Glycine max (L.) Merr.] seeds with Zn, however, is still not well known as regards the uptake and mobilization dynamics of the nutrient during the germination process. This study aimed to evaluate the uptake and distribution dynamics of Zn applied to soybean seeds at two levels of vigor during germination using X-ray micro-fluorescence spectroscopy (µ-XRF). Zinc treatments corresponded to 0, 2, 4 and 8 g of Zn per kg of seeds. High and low vigor seeds that had been treated were located appropriately so as to promote germination. Zn intensity measurements with µ-XRF were taken in different parts ("regions") of the seeds (seed coat, cotyledon, and embryonic axis) after 8, 16 and 24 h of imbibition and seedlings (primary root, hypocotyl, plumule, cotyledon, and seed coat) after 48, 72 and 96 h of germination. High vigor seeds showed higher Zn intensity in the embryonic axis in the first 16 h, while low vigor seeds showed higher intensity after 24 h. After 48, 72 and 96 h of germination low vigor seedlings showed higher Zn intensity than high vigor seedlings in the primary root. It was concluded that µ-XRF is an efficient technique for identifying variances in the dynamics of Zn uptake and mobilization during the germination of soybean seeds with different vigor levels.

Physical and physiological qualities and productivity of corn seeds fertilized with poultry waste / Avaliação das qualidades física e fisiológica e da produtividade de sementes de milho adubado com resíduo avícola

This study evaluated the physical and physiological qualities and productivity of corn seeds, a variety UFVM 100 Native, produced in plots fertilized in top dressing with different levels of poultry waste. The experiment was organized in a randomized block design, with six treatments and four repetitions, totaling 24 plots. The treatments consisted of the application of 0.0, 1.5, 3.0, 4.5, 6.0, and 7.5 t/ha of tanned poultry waste. The seeds were subjected to the following evaluations: uniformity test, thousand seed weight, germination, vigor (first germination count, accelerated aging, soilless cold test, percentage, and emergence rate in sand), and productivity. Linear regression models were used to evaluate the effects of different dosages of poultry waste on the variables considered. The quality of seeds was not influenced by the effects of different levels of fertilization. Among the dosages used, 7.5 t/ha is recommended because it provides a greater increase in productivity, which may result in a greater financial return to the producer.

Este trabalho teve como objetivo avaliar as qualidades física e fisiológica, bem como a produtividade das sementes de milho, variedade UFVM 100 Nativo, produzidas em lavouras adubadas com diferentes níveis de resíduo avícola, em cobertura. O experimento foi instalado no delineamento em blocos casualizados, com seis tratamentos e quatro repetições, totalizando 24 parcelas. Os tratamentos consistiram da aplicação de 0,0; 1,5; 3,0; 4,5; 6,0 e 7,5 t/ha de resíduo avícola curtido. As sementes foram submetidas às seguintes avaliações: Teste de uniformidade, peso de mil sementes, germinação, vigor (primeira contagem de germinação, envelhecimento acelerado, teste de frio sem solo, porcentagem e velocidade de emergência em areia) e produtividade. Para avaliar o efeito das diferentes dosagens de resíduo avícola sobre as variáveis consideradas foram utilizados modelos de regressão linear. A qualidade das sementes não foi influenciada pelo efeito dos diferentes níveis de adubação. Dentre as dosagens utilizadas, recomenda-se a de 7,5 t/ha por proporcionar maior aumento da produtividade, o que poderá resultar em maior retorno financeiro ao produtor.

Physiological quality of soybean seeds produced under shading / Qualidade fisiológica de sementes de soja produzidas sob sombreamento

Low light intensity reduces the production of photoassimilates by plants and consequentlythe accumulation of reserves in seeds. The objective was to evaluate the physiological quality of soybean seeds produced under shading initiated at different crop phenological stages. In a completely randomized design, the experiment was carried out in a greenhouse, at CAV/UDESC, during the 2018/2019 harvest, with nine treatments and 10 replications. The treatments consisted of nine seed lots, eight of which were obtained from plants submitted to continuous 70% shading, initiated at different phenological stages: stage V6 (Day Julian 07); R1 (JD14); R2 (JD21); R3 (JD28); R4 (JD35); R5 (JD42); start of R6 (JD49); end of R6 (JD56), and a lot of seeds produced without shading (control). Each repetition consisted of a pot containing a soybean plant. The germination potential and vigor of the seeds produced were evaluated. Soybean seed germination was higher in the lot of seeds from shaded plants from the R4 stage (JD35), with 98%, but the other lots presented percentages above 87%. The vigor in the accelerated aging test was lower for the lot obtained from shaded plants from V6, with 43%. The dry mass of seedlings showed a 7.0 to 13.3% reductionin relation to the controlwhen the shading was imposed between R3 and R6. It was concluded that the continuous 70% shading in soybeans promoted higher seed germination when imposed from the R4 stage;however, the vigor was dependenton the stage that the shading started and the test used.(AU)

A baixa intensidade luminosa reduz a produção de fotoassimilados pelas plantas e consequentemente o acúmulo de reservas nas sementes. Objetivou-se avaliar a qualidade fisiológica de sementes desoja produzidassob sombreamento iniciado emdiferentes estádios fenológicos da cultura. O experimento foi conduzido em casa de vegetação, no CAV/UDESC, durante a safra 2018/2019, em delineamento inteiramente casualizado, com nove tratamentos e 10 repetições. Os tratamentos foram constituídos por nove lotes de sementes, sendo oito obtidos de plantas submetidas a sombreamento contínuode 70%, iniciado em diferentes estádios fenológicos: estádio V6 (Dia Juliano 07); R1 (DJ 14); R2 (DJ 21); R3 (DJ 28); R4 (DJ35); R5 (DJ 42); início de R6 (DJ 49); finalde R6 (DJ 56), e um lote de sementes produzidas sem sombreamento (testemunha). Cada repetição foi composta por um vaso contendo uma planta de soja. Avaliou-se o potencial de germinação e vigor das sementes produzidas. Agerminação de sementes de soja foi maior no lote de sementes oriundas de plantas sombreadas a partir do estádio R4 (35 DJ), com 98%, mas, os demais lotes apresentaram percentuais acima de 87%. O vigor no teste de envelhecimento acelerado foi inferior parao loteobtido de plantas sombreadasa partir de V6, com 43%. Já a massa seca de plântulas apresentou redução de 7,0 a 13,3% em relação à testemunha, quando o sombreamento foi imposto entre R3 e R6. Concluiu-se que o sombreamento contínuo de 70% em soja promoveu maior germinação de sementes quando imposto a partir do estádio R4, porém, o vigor foi afetado de maneira dependente do estádio que o sombreamento iniciou e do teste utilizado.(AU)

Physiological quality of soybean seeds produced under shading / Qualidade fisiológica de sementes de soja produzidas sob sombreamento

A baixa intensidade luminosa reduz a produção de fotoassimilados pelas plantas e consequentemente o acúmulo de reservas nas sementes. Objetivou-se avaliar a qualidade fisiológica de sementes de soja produzidas sob sombreamento iniciado em diferentes estádios fenológicos da cultura. O experimento foi conduzido em casa de vegetação, no CAV/UDESC, durante a safra 2018/2019, em delineamento inteiramente casualizado, com nove tratamentos e 10 repetições. Os tratamentos foram constituídos por nove lotes de sementes, sendo oito obtidos de plantas submetidas a sombreamento contínuo de 70%, iniciado em diferentes estádios fenológicos: estádio V6 (Dia Juliano 07); R1 (DJ 14); R2 (DJ 21); R3 (DJ 28); R4 (DJ 35); R5 (DJ 42); início de R6 (DJ 49); final de R6 (DJ 56), e um lote de sementes produzidas sem sombreamento (testemunha). Cada repetição foi composta por um vaso contendo uma planta de soja. Avaliou-se o potencial de germinação e vigor das sementes produzidas. A germinação de sementes de soja foi maior no lote de sementes oriundas de plantas sombreadas a partir do estádio R4 (35 DJ), com 98%, mas, os demais lotes apresentaram percentuais acima de 87%. O vigor no teste de envelhecimento acelerado foi inferior para o lote obtido de plantas sombreadas a partir de V6, com 43%. Já a massa seca de plântulas apresentou redução de 7,0 a 13,3% em relação à testemunha, quando o sombreamento fo

Low light intensity reduces the production of photoassimilates by plants and consequently the accumulation of reserves in seeds. The objective was to evaluate the physiological quality of soybean seeds produced under shading initiated at different crop phenological stages. In a completely randomized design, the experiment was carried out in a greenhouse, at CAV/UDESC, during the 2018/2019 harvest, with nine treatments and 10 replications. The treatments consisted of nine seed lots, eight of which were obtained from plants submitted to continuous 70% shading, initiated at different phenological stages: stage V6 (Day Julian 07); R1 (JD 14); R2 (JD 21); R3 (JD 28); R4 (JD 35); R5 (JD 42); start of R6 (JD 49); end of R6 (JD 56), and a lot of seeds produced without shading (control). Each repetition consisted of a pot containing a soybean plant. The germination potential and vigor of the seeds produced were evaluated. Soybean seed germination was higher in the lot of seeds from shaded plants from the R4 stage (JD 35), with 98%, but the other lots presented percentages above 87%. The vigor in the accelerated aging test was lower for the lot obtained from shaded plants from V6, with 43%. The dry mass of seedlings showed a 7.0 to 13.3% reduction in relation to the control when the shading was imposed between R3 and R6. It was concluded that the continuous 70% shading in soybeans promot

Does silicon attenuate PEG 6000-induced water deficit in germination and growth initial the seedlings corn / O silício atenua o déficit hídrico induzido pelo PEG 6000 na germinação e crescimento inicial das mudas de milho

Water stress limits the initial growth and development of maize mass and grain, as well as the physiological process for absorbing the amount of mineral elements. The objective was to evaluate the effect of silicon on germination and growth of corn seedlings submitted to water deficit. The experiment was carried out in the laboratory and the experimental design was completely randomized (factorial 3 × 4), with three concentrations of calcium silicate (0.0; 1.0 and 2.0 mM) and 4 solutions of PEG-6000 to simulate different osmotic potentials (0, 0; -0.3; -0.6; -0.9 MPa). Germination percentage, germination speed index (GSI), mean germination time (MGT), percentage of non-germinated and abnormal germinated, length and dry matter of shoot, root and total seedlings were evaluated. Water deficiency reduced the parameters TG, GSI and MGT. The water deficit reduce the MSPA, MSR and MST with more than 80% reduction in mass from seedlings without deficiency to seedlings with deficiency. For CPA, CR and CT there was a reduction of at least 87%, 70% and 77%, respectively, among seeds without deficiency compared to seeds submitted to deficiency. The use of silicon in corn seeds did not attenuate the stress caused by water deficit simulated by PEG-6000.

O estresse hídrico limita o crescimento inicial e o desenvolvimento da massa e do grão de milho, assim como no processo fisiológico para a absorção da quantidade de elementos minerais. Objetivou-se avaliar o efeito do silício na germinação e no crescimento de plântulas de milho submetidas a deficiência hídrica. O experimento foi desenvolvido em laboratório e o delineamento experimental foi inteiramente casualizado (DIC) (fatorial 3 × 4), sendo três concentrações de Silicato de cálcio (0,0; 1,0 e 2,0 mM) e 4 soluções de PEG-6000 a simular diferentes potenciais osmóticos (0,0; -0,3; -0,6; -0,9 MPa). Foram avaliados a porcentagem de germinação, o índice de velocidade de germinação (IVG), o tempo médio de germinação (TMG), a porcentagem de não germinadas e de germinadas anormais, o comprimento e matéria seca da parte aérea, raiz e total das plântulas. A deficiência hídrica diminuiu os parâmetros TG, IVG e TMG. O déficit hídrico reduz a MSPA, MSR e MST com mais de 80% de redução da massa das plântulas sem deficiência para as plântulas com deficiência. Para CPA, CR e CT houve redução de, no mínimo, 87%, 70% e 77%, respectivamente entre as sementes sem deficiência em comparação as sementes submetidas a deficiência. A utilização de silício em sementes de milho não atenuou o estresse causado pela deficiência hídrica simulada por PEG-6000.

Influence of essential oils on the quality of Vigna unguiculata L. (Walp.) seeds compared by traditional method, image and multivariate analysis / Influência de óleos essências na qualidade de sementes de Vigna unguiculata L. (Walp.) comparado pelo método tradicional, análise imagem e multivariada

The extracts of medicinal plants are used for the treatment of seeds in order to reduce the action of phytopathogens and increase the vigor of the seeds. Currently, computerized image analysis has been used to assess the physiological quality of seed lots. The objective was to evaluate the efficiency of the Vigor-S® software in the evaluation of the physiological quality of cowpea seeds treated with essential oils, comparing with a traditional test and the principal component analysis. Two cowpea cultivars were analyzed, BRS Tumucumaque and BRS Guariba, treated with doses of natural extracts of Alfavaca, garlic, horsetail, citronella and pyroligneous acid. The traditional method consisted of evaluations for germination, first germination count, seedling emergence, emergence speed index, accelerated aging, fresh matter and dry matter of seedling and the image analysis for: seedling length, growth index, uniformity index, vigor index, and germination. A Principal component analysis was applied to reduce the number of variables. Horsetail, Alfavaca and citronella extracts were efficient in increasing the physiological quality of the seeds of at least one cultivar. The Vigor-S® software proved to be efficient compared to traditional tests to assess the physiological quality of seeds. Principal Component Analysis is an ally to identify the best extracts and doses to be used. The image analysis method proved to be effective when compared to the traditional method and can therefore be used.

Os extratos de plantas medicinais são utilizados para o tratamento de sementes com o objetivo de diminuir a ação de fitopatógenos e aumentar o vigor das sementes. Atualmente, a análise computadorizada de imagens tem sido utilizada para avaliar a qualidade fisiológica de lotes de sementes. O objetivo foi avaliar a qualidade fisiológica de sementes de feijão-caupi tratadas com óleos essenciais, comparado com teste tradicional, análise imagem e a análise de componentes principais. Foram analisadas duas cultivares de feijão-caupi, BRS Tumucumaque e BRS Guariba, tratadas com doses de extratos naturais de alfavaca, alho, cavalinha, citronela e ácido pirolenhoso. O método tradicional consistiu em avaliações de germinação, primeira contagem de germinação, emergência de plântulas, índice de velocidade de emergência, envelhecimento acelerado, matéria fresca e matéria seca da plântula e a análise de imagem para: comprimento da plântula, índice de crescimento, índice de uniformidade, índice de vigor e germinação. Uma análise de componentes principais foi aplicada para reduzir o número de variáveis. Os extratos de cavalinha, alfavaca e citronela foram eficientes em aumentar a qualidade fisiológica das sementes de pelo menos uma cultivar. O software Vigor-S® mostrou-se eficiente em relação aos testes tradicionais para avaliação da qualidade fisiológica de sementes. A Análise de Componentes Principais é uma aliada para identificar os melhores extratos e doses a serem utilizados. O método de análise de imagens mostrou-se eficaz quando comparado ao método tradicional, podendo, portanto, ser utilizado.

Effect of the association between insecticide and biostimulant on the physiological quality of rice seeds / Efeito da associação entre inseticida e bioestimulante na qualidade fisiológica de sementes de arroz

The seed is thevehicle for high productivity crops, as it carries the genetic potential and technology necessary for the success of a crop. And seed treatment has been a very important technology for the initial development of rice seeds. For this reason, the objective of this work was to evaluate the influence of seed treatment withCruiser Opti insecticide associated with the biostimulant EpívioTM at different dosages and during 0, 60, 90, 135 and 180 days after seed treatment. Rice seeds of the cultivar IRGA 424 RI were used. The treatments were: Control: Permit + Standk + Gaucho, T2-Cruiser Opti (0.5 L/100 Kg of seeds), T3 -EpivioTM (0.1 L/100 Kg of seeds), T4 -Cruiser Opti + EpivioTM (0.5 + 0.05 L/100 kg of seeds), T5 -Cruiser Opti + EpivioTM (0.5 + 0.1 L/100 kg of seeds) and T6 ­(0.5 + 0.2 L/100 kg of seeds). Seed quality was monitored through the germination test, cold test and emergence in trays. Under the conditions in which the work was carried out, we can conclude that the treatment composed of Cruiser Opti + EpivioTM, at a dose of 0.5 and 0.1 L/100Kg of seeds, respectively, provided better performance in the germination test in the evaluated periods when compared to the other treatments.(AU)

A semente é o veículo para lavouras de alta produtividade, pois carrega em si o potencial genético e tecnologia necessários para o sucesso de uma safra.E o tratamento de sementes vem sendo uma tecnologia de grande importante para o desenvolvimento inicial das sementes de arroz.Por este motivo,oobjetivo deste trabalho foi avaliar a influência do tratamento de sementes, com inseticida Cruiser Opti associado ao bioestimulante EpívioTMem diferentes dosagens e durante 0, 60, 90, 135 e 180 dias após o tratamento de sementes. Utilizou-se sementes de arroz da cultivar IRGA 424 RI. Os tratamentos foram: Testemunha: Permit + Standk + Gaucho, T2-Cruiser Opti (0,5 L/100 Kg de sementes), T3 -EpívioTM(0,1 L/100 Kg de sementes), T4 -Cruiser Opti + EpivioTM(0,5 + 0,05 L/100 kg de sementes), T5 -Cruiser Opti + EpivioTM(0,5 + 0,1 L/100 kg de sementes) e T6 ­(0,5 + 0,2 L/100 kg de sementes). A qualidade das sementes foi monitorada através do teste germinação, teste de frio e emergência em bandejas. Nas condições de realização do trabalho podemos concluir que otratamento composto por Cruiser Opti + EpivioTM, na dose de 0,5 e 0,1 L/100Kg de sementes, respectivamente, conferiram melhor desempenho no teste de germinação nos períodos avaliados quando comparado aos demais tratamentos.(AU)

Physiological and sanitary quality of wheat cultivars seeds subjected to chemical and biological seed treatments / Qualidade fisiológica e sanitária de sementes de cultivares de trigo submetidas a tratamentos de sementes químico e biológico

Brazilian wheat farming is characterized by a high occurrence of seed-transmitted diseases that can cause significant damage to grain production. The objective of this study was to evaluate the influence of seed treatments on the physiological and sanitary quality of wheat cultivar seeds. Seeds from three commercial wheat cultivars (TBIO Sossego, TBIO Sinuelo, and TBIO Toruk) were used, along with four seed treatments (Control, Chemical, Biological, and Chemical + Biological). The physiological quality of the seeds was determined based on first germination count, germination percentage, quantification of abnormal seedlings, shoot and radicle length, whole seedling dry weight, and emergence velocity index (EVI). The sanitary quality was assessed using the Blotter test. Overall, the chemical treatment combined with the seeds of the TBIO Toruk cultivar provided better indices of physiological and sanitary quality.(AU)

A triticultura brasileira é marcada pela elevada ocorrência de doenças transmitidas via sementes, capazes de causar danos à produção de grãos. Objetivou-se avaliar a influência de tratamentos de sementes na qualidade fisiológica e sanitária de sementes de cultivares de trigo. Foram utilizadas sementes de três cultivares comerciais de trigo (TBIO Sossego, TBIO Sinuelo e TBIO Toruk) e quatro tratamentos de sementes (Controle, Químico, Biológico e Químico + Biológico). A qualidade fisiológica das sementes foi determinada com base nos testes de primeira contagem de germinação, germinação, quantificação número de plântulas anormais, comprimento de parte aérea e radícula, massa seca de plântula inteira e índice de velocidade de emergência (IVE). A qualidade sanitária foi determinada através do Blotter test. Em geral, o tratamento químico associado às sementes da cultivar TBIO Toruk proporcionou melhores índices de qualidade fisiológica e sanitária.(AU)

Viability and vigor of soybean seeds as a result of industrial seed treatment and stored in different environments / Viabilidade e vigor de sementes de soja em função do tratamento industrial de sementes e armazenadas em diferentes ambiente

The industrial seed treatment (IST) of soybeans is an economically recommended technique in agricultural production, providing protection against pests and initial pathogens. However, the real effects of pesticides about the quality of soybean seeds are still little known, since the adoption of the system is still recent by soybean farmers. The objective of this work was to evaluate the physiological quality of soybean seeds, treated or not, with insecticide/ fungicide new mixtures and stored for 240 days in a non-controlled and controlled environment. The completely randomized design was used, distributed in a 5 x 2 x 6 factorial scheme with four replications. The plot treatments consisted of soybean seeds belonging to the cultivar M - 7739 IPRO, treated with six different insecticide/ fungicide mixtures {(Cruiser®); (Amulet®); (MaximAdvanced®); (Cruiser®+ MaximAdvanced®); (MaximAdvanced® + Amulet®); (untreated control)}, stored in two environments {(laboratory ­ without control and cold room ­ with control (10 ± 2 ºC,45± 2% UR)} for eight months of storage with five evaluation times (0; 60; 120; 180 and 240days). The following tests were carried out: water content, germination, first count, seedling length and seedling dry mass. It was found that the chemical treatments negatively affect the germination potential of seeds, especially after 120 days of storage, regardless of the environment.Thiamethoxamand Thiamethoxam + Metalaxil; Tabendazole; Fludioxonil after storage provided the biggest reductions in seed viability and vigor after 240 days of storage. The cold room environment provides better conditions for the conservation of the germinative potential of soybean seeds.

O tratamento industrial de sementes (TIS) de soja é uma técnica economicamente recomendada na produção agrícola, proporcionando proteção contra pragas e patógenos iniciais. No entanto, os reais efeitos dos agrotóxicos sobre a qualidade das sementes de soja ainda são pouco conhecidos, visto que a adoção do sistema ainda é recente pelos sojicultores. Objetivou-se com este trabalho avaliar a qualidade fisiológica das sementes de soja, tratadas ou não, com novas misturas de inseticidas/fungicidas, e armazenadas por 240 dias, em diferentes ambientes. O delineamento experimental utilizado foi inteiramente casualizado, distribuído em esquema fatorial 5 x 2 x 6, com quatro repetições. Os tratamentos das parcelas foram constituídos de sementes de soja pertencentes à cultivar M ­ 7739 IPRO, tratadas com seis diferentes misturas produtos de inseticida/fungicida {(Cruiser® - Tiametoxam ­ 200 mL + Bio Cromo ­ 100 mL); (Amulet® - Fipronil - 100 mL + Bio Cromo ­ 100 mL); (MaximAdvanced® - Metalaxil-M; Tabendazol; Fludioxonil ­ 100 mL + Bio Cromo ­ 100 mL ); (Cruiser® - Tiametoxam ­ 200 mL + MaximAdvanced® - Metalaxil-M; Tiabendazol; Fludioxonil ­ 100 mL + Bio Cromo ­ 100mL ); (MaximAdvanced® - Metalaxil-M; Tabendazol; Fludioxonil ­ 100 mL + Amulet® - Fipronil - 100 mL + BioCromo ­ 100mL); (controle não tradada)}, armazenadas em dois ambientes {(laboratório ­ sem controle e câmara fria ­ com controle (10 ± 2 ºC,45± 2% UR)} durante oito meses de armazenamento, com cinco tempos de avaliações (0; 60; 120; 180 e 240dias). Os seguintes testes foram realizados: teor de água, germinação, primeira contagem, comprimento das plântulas, massa seca de plântulase índice de velocidade de emergência. Verificou-se que o ambiente de câmara fria proporciona melhores condições para a conservação do potencial germinativo das sementes de soja. Os tratamentos químicos interferem negativamente no potencial germinativo das sementes, sobretudo após 120 dias de armazenamento, independente do ambiente. Tiametoxam e Tiametoxam + Metalaxil; Tabendazol; Fludioxonil após o armazenamento proporcionaram as maiores reduções da viabilidade e vigor das sementes após 240 dias de armazenamento. O ambiente de câmara fria proporciona melhores condições para a conservação do potencial germinativo das sementes de soja.

Germination of Amaranthus deflexus L. seeds subjected to different temperature and salt-stress conditions / Germinação de sementes de Amaranthus deflexus L. submetidas a diferentes condições de temperatura e estresse salino

Weeds compete with crops for limiting factors in the environment in which they live; therefore, studies that demonstrate the germination response of seeds subjected to artificial stress are important to understand the survival and adaptation capacities of these species under natural stress conditions. This study proposes to evaluate the effect of salinity and thermal conditions on the germination and vigor of seeds of Amaranthus deflexus L. Two experiments were conducted with sowing in Petri dishes containing two sheets of filter paper moistened with distilled water (control) or NaCl solutions. In experiment 1, a completely randomized experimental design was adopted with a 2 × 6 factorial arrangement consisting of two photoperiods (12 h light and 24 h dark) and six levels of salt stress (0, -0.3, -0.6, -0.9, -1.2, and -1.5 MPa), totaling twelve treatments, with four replications. At the end of the test, the seeds that did not germinate were washed and placed on paper towel substrate, which was moistened with water for hydration and to stimulate the germination process. Experiment 2 was also laid out in a completely randomized design and involved eight treatments (germination at 20, 25, 30, 35, 40, 20/30, 25/35, and 30/40 °C) and four replicates each. Salt stress negatively affected the seed vigor of A. deflexus from the stress level of -0.3 MPa. The absence of light compromised seed vigor, regardless of the stress level applied. The final germination percentage and the germination speed index of A. deflexus seeds were superior at the constant temperature of 25 °C and in the alternating regime of 25-35 °C. The multivariate procedure discriminated treatments 1 and 2 as superior in dendrogram A, as well as 4, 5, and 6 in dendrogram B, making it a robust method for inference in factorial experiments on germination behavior.

As plantas daninhas competem com as culturas por fatores limitantes do meio em que vivem, portanto, estudos que apontem a resposta germinativa de sementes submetidas a estresses artificiais são importantes para entender a capacidade de sobrevivência e adaptação destas espécies sob condições de estresse naturais. Objetivou-se neste trabalho avaliar o efeito das condições salinas e térmicas sobre a germinação e vigor de sementes de Amaranthus deflexus L. Foram instalados dois experimentos, com semeadura realizada em placas de petri contendo duas folhas de papel de filtro umedecidas com água destilada (controle) ou com soluções de NaCl. No experimento 1 utilizou-se o delineamento experimental inteiramente casualizado (DIC), em esquema fatorial 2 x 6, constituído de dois fotoperíodos (12h luz e 24h escuro) e seis níveis de estresse salino (0; -0,3; -0,6; -0,9; -1,2 e -1,5 MPa), totalizando doze tratamentos, com quatro repetições. Ao final do teste, as sementes que não germinaram foram lavadas e colocadas em substrato papel toalha, umedecido com água para hidratação e estimular o processo germinativo. No experimento 2 utilizou-se um DIC com oito tratamentos (germinação sob 20; 25; 30; 35; 40°C, 20/30; 25/35 e 30/40°C) e quatro repetições cada. O estresse salino afetou negativamente o vigor das sementes de A. deflexus desde o nível de estresse de -0,3 MPa. O vigor das sementes foi comprometido pela ausência de luz, independentemente dos níveis de estresse aplicados. Houve superioridade na percentagem final de germinação e o índice de velocidade de germinação das sementes de A. deflexus na temperatura de 25°C constante e no regime alternado de 25-35°C. O procedimento multivariado discriminou os tratamentos 1 e 2 como superiores no dendograma A, bem como 4, 5 e 6 no dendograma B, configurando-se como método robusto para inferência em experimentos fatoriais sobre o comportamento germinativo.

Production and Physiological Quality of Seeds of Mini Watermelon Grown in Substrates with a Saline Nutrient Solution Prepared with Reject Brine.

The economically profitable production of crops is related, among other factors, to seed quality, the production system, and the water used in irrigation or preparation of nutrient solutions. Therefore, the objective was to evaluate the phenology, production, and vigor of seeds of mini watermelons grown in saline nutrient solution and different substrates. In the fruit and seed production phase, the experiment occurred in a greenhouse with five electrical conductivities of water for nutrient solution preparation, ECw (0.5, 2.4, 4.0, 5.5, and 6.9 dS m-1), and two growing substrates (coconut fiber and sand). We evaluated the physiological quality of seeds previously produced under the five electrical conductivities of water and two substrates. High salinities for the hydroponic cultivation of the mini watermelon cultivar 'Sugar Baby' accelerated fruit maturation and crop cycle, decreasing fruit size. However, in both substrates, the seed production of mini watermelons, seed viability, and seed vigor occurred adequately with a reject brine of 6.9 dS m-1 in the hydroponic nutrient solution. The seed production of 'Sugar Baby' mini watermelons using reject brine in a hydroponic system with coconut fiber and sand substrates is viable in regions with water limitations.

Aspergillus niger as a Biological Input for Improving Vegetable Seedling Production.

This study evaluated the potential of Aspergillus niger as an inoculant for growth promotion of vegetable seedlings. Seven vegetable species were evaluated in independent experiments carried out in 22 + 1 factorial schemes, with two doses of conidia (102 and 106 per plant) applied in two inoculation methods (seed treatment and in-furrow granular application), plus an uninoculated control. Experiments were carried out in a greenhouse. Growth parameters evaluated were shoot length, stem diameter, root volume, total root length, shoot and root fresh mass, shoot and root dry mass, and total dry mass. Regardless of the dose and inoculation method, seedlings inoculated with A. niger showed higher growth than uninoculated ones for all crops. The highest relative increase promoted by the fungus was observed for aboveground parts, increasing the production of shoot fresh mass of lettuce (61%), kale (40%), scarlet eggplant (101%), watermelon (38%), melon (16%), pepper (92%), and tomato (42%). Aspergillus niger inoculation also increased seedling root growth of lettuce, pepper, scarlet eggplant, watermelon, and tomato. This research shows that A. niger boosts the growth of all analyzed vegetables, appearing as a promising bio-input for vegetable seedling production.