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Plant regulators are studied because they can alter commercially significant aspects of plant growth. Gibberellic acid (GA3) exemplifies this, as it plays a crucial role in the growth and flowering processes of various vegetables. Thus, the present study sought to verify the effects caused by the exogenous application of different doses of the plant regulator GA3 on the floral, vegetative, and physiological patterns of the orchid Oncidium baueri. The sprayed doses were: 0, 50, 100, 200, and 400 mg L-1 of GA3. The parameters measured were: pseudobulb length (PL) and width (PW), leaf length (LL), leaf width (LW), number of leaves per plant (NL); time for flower spike to sprout (TFSS), time for flowers to open fully (TFOF), and time for flowers to fall (TFF), these measured in days; flower stem size (FSS), number of flowers per stem (NFS), chlorophyll a fluorescence (fv/fm), and stomatal conductance (Gs). The concentration of 200 mg L-1 of GA3 increased CP and CF by 3 cm, and NL also increased compared with the other concentrations. Regarding floral aspects, this same dose showed the lowest TFSS, distinguishing itself from the other treatments. For physiological parameters, this dose also resulted in higher fv/fm (0.826) and Gs (65.340 mmol m-2 s-1). Therefore, the use of 200 mg L-1 of GA3 is recommended for O. baueri plants to optimize vegetative and floral promotion.

Abstract Soybean is the main oilseed cultivated worldwide. Even though Brazil is the world’s largest producer and exporter of soybean, its production is severely limited by biotic factors. Soil borne diseases are the most damaging biotic stressors since they significantly reduce yield and are challenging to manage. In this context, the present study aimed to evaluate the potential of a bacterial strain (Ag109) as a biocontrol agent for different soil pathogens (nematodes and fungi) of soybean. In addition, the genome of Ag109 was wholly sequenced and genes related to secondary metabolite production and plant growth promotion were mined. Ag109 showed nematode control in soybean and controlled 69 and 45% of the populations of Meloidogyne javanica and Pratylenchus brachyurus, respectively. Regarding antifungal activity, these strains showed activity against Macrophomia phaseolina, Rhizoctonia solani, and Sclerotinia sclerotiorum. For S. sclerotiorum, this strain increased the number of healthy plants and root dry mass compared to the control (with inoculation). Based on the average nucleotide identity and digital DNA-DNA hybridization, this strain was identified as Bacillus velezensis. Diverse clusters of specific genes related to secondary metabolite biosynthesis and root growth promotion were identified, highlighting the potential of this strain to be used as a multifunctional microbial inoculant that acts as a biological control agent while promoting plant growth in soybean.

Devido ao recente aumento no custo do germoplasma, royalties de biotecnologia e tratamentos de sementes, estudos vêm sendo realizados para analisar a capacidade das cultivares modernas de soja, de manter o rendimento de grãos sob densidades de semeadura (DS) reduzidas. Este estudo objetivou elucidar o efeito da redução da DS no índice de área foliar (IAF) e na interceptação de luz pelo dossel de cultivares de soja com potencial de ramificação contrastantes e identificou a associação dessas variáveis com o rendimento de grãos. Os experimentos de campo foram conduzidos em blocos casualizados, utilizando-se as cultivares BRS 1010IPRO (alta plasticidade) e NS 5959IPRO (média plasticidade), com cinco DS: 100, 80, 60, 40 e 20% da DS recomendada. A redução da DS não reduziu o rendimento de grãos até o ponto em que o IAF e a interceptação luminosa na fase reprodutiva foram semelhantes aos obtidos com a DS recomendada. Maior IAF e interceptação luminosa em cultivares com maior plasticidade de ramificação conferem maior potencial de redução da DS. A densidade de semeadura mínima ótima (DSMO) para IAF, Índice de Vegetação por Diferença Normalizada (NDVI) e radiação fotossinteticamente ativa interceptada (RFAI) acumulados, na fase reprodutiva foi mais próximo da DSMO para produção de grãos do que na fase vegetativa ou no ciclo total da cultura, indicando “crescimento de luxo” na fase vegetativa nas DS recomendadas. O IAF, o NDVI e a RFAI acumulados na fase reprodutiva tiveram maior correlação com o rendimento de grãos do que aqueles na fase vegetativa ou no ciclo total. O NDVI acumulado apresentou maior correlação com o rendimento de grãos do que o IAF e a RFAI acumulados.

ABSTRACT: Organic agriculture comprises farming practices that discard synthetic pesticides and fertilizers. Tomato production demands huge amounts of fertilizers and pesticides. Improving efficiency of the inputs allowed for organic tomato production is a challenge to upgrade yields. Thereby, we studied the effects of the inoculation of the arbuscular mycorrhizal fungus (AMF) Rhizophagus clarus, supplying rock thermophosphate and bioactivator, alone or associated, on tomato development and yield. The experiment was achieved in a greenhouse using undetermined tomato cv. BRS-Nagai sown in polystyrene trays and afterwards transplanted to pots. Treatments included R. clarus; thermophosphate (TH) (130 g/pot); bioactivator (PenergeticK® + Penergetic®) (BI); R. clarus + TH; R. clarus + BI; R. clarus + TH+ BI and TH + BI and control (CO). From the flowering onset, plant height, height of insertion of first truss, trusses space, length, and also the diameter and fresh weight of ripe fruits of the three first trusses were assessed. AMF colonization in the roots and macronutrients in leaves and petioles were also measured. Trusses spacing variable was affected by mycorrhiza and thermophosphate. R. clarus inoculation incremented 10 and 31.85% of fresh mass of ripe fruits and mass of ripe fruits per plant, respectively. Soluble solids contents in fruits and N, P and K in the leaves and petioles were similar among treatments. AMF colonization decreased on thermophosphate fertilized plants and increased in bioactivator treatment. Results showed that root inoculation with R. clarus promoted better plant development and yield and may be used as biological inoculant mostly on organic tomato production.

Sericulture is the cultivation of silkworms to produce silk using white mulberry leaves (Morus alba L.); thus, the sector's quality production of mulberry seedlings on a large scale is economically important. The production of seedlings through cuttings is the most effective and fastest reproduction method. Still, it can also be enhanced using synthetic rooting agents, increasing the productive potential of white mulberry crops. The current work aims to evaluate the response of cuttings taken from different parts of the branch of M. alba var. Miura (Apical 1, Apical 2, Medial, Basal 1, and Basal 2) and treated with indolebutyric acid (IBA; 500, 1,000, and 1,500 mg L-1) and commercial rooting agent Forth® (10 % v/v), in addition to a control treatment. After treating the branches, they were placed in polyethylene containers filled with substrate and kept in a greenhouse for 70 days. The application of hormones on cuttings of M. alba favored several morpho-agronomic parameters evaluated for the propagules obtained from different positions on the branch. In conclusion, applying 500 or 1,000 mg L-1 of IBA is recommended for the various positions, with Basal 1 and Basal 2 showing higher values ​​in the evaluated parameters than the other positions. The results can help silk breeders optimize white mulberry crop production.

Abstract The objective of this work was to evaluate cryoprotectants on the physiological quality of Adenium obesum seeds preserved in liquid nitrogen. The following treatments were used: T1, control, without cryoprotectant and without immersion in liquid nitrogen; T2, with immersion in liquid nitrogen and without cryoprotectant; T3, with 0. 4 mol L-1 sucrose; T4, with 0.8 mol L-1 sucrose; T5, with 1.0 mol L-1 glycerol; T6, with 2.0 mol L-1 glycerol with PVS1; T7, with PVS1; T8, with PVS2; T9, with PVS2 + phloroglucinol (modified PVS2); and T10, with PVS3. Adenium obesum seeds show tolerance to immersion and storage in liquid nitrogen and do not need cryoprotectants to maintain their physiological quality when stored in a water content of 7.5%.

Abstract Soybean and maize are some of the main drivers of Brazilian agribusiness. However, biotic and abiotic factors are of great concern, causing huge grain yield and quality losses. Phosphorus (P) deficiency is important among the abiotic factors because most Brazilian soils have a highly P-fixing nature. Thus, large amounts of phosphate fertilizers are regularly applied to overcome the rapid precipitation of P. Searching for alternatives to improve the use of P by crops is essential to reduce the demand for P input. The use of multifunctional rhizobacteria can be considered one of these alternatives. In this sense, the objective of the present work was to select and validate bacterial strains with triple action (plant growth promoter, phosphate solubilizer, and biocontrol agent) in maize and soybean, aiming to develop a multifunctional microbial inoculant for Brazilian agriculture. Bacterial strains with high indole acetic acid (IAA) production, phosphate solubilization, and antifungal activity against soil pathogenic fungi (Rhizoctonia solani, Macrophomina phaseolina, and Fusarium solani) were selected from the maize rhizosphere. Then, they were evaluated as growth promoters in maize under greenhouse conditions. Based on this study, strain 03 (Ag75) was selected due to its high potential for increasing biomass (root and shoot) and shoot P content in maize. This strain was identified through genomic sequencing as Bacillus velezensis. In field experiments, the inoculation of this bacterium increased maize and soybean yields by 17.8 and 26.5%, respectively, compared to the control (25 kg P2O5). In addition, the inoculation results did not differ from the control with 84 kg P2O5, indicating that it is possible to reduce the application of phosphate in these crops. Thus, the Ag75 strain has great potential for developing a multifunctional microbial inoculant that combines the ability to solubilize phosphate, promote plant growth, and be a biocontrol agent for several phytopathogenic fungi.

ABSTRACT Regression analysis is highly relevant to agricultural sciences since many of the factors studied are quantitative. Researchers have generally used polynomial models to explain their experimental results, mainly because much of the existing software perform this analysis and a lack of knowledge of other models. On the other hand, many of the natural phenomena do not present such behavior; nevertheless, the use of non-linear models is costly and requires advanced knowledge of language programming such as R. Thus, this work presents several regression models found in scientific studies, implementing them in the form of an R package called AgroReg. The package comprises 44 analysis functions with 66 regression models such as polynomial, non-parametric (loess), segmented, logistic, exponential, and logarithmic, among others. The functions provide the coefficient of determination (R2), model coefficients and the respective p-values from the t-test, root mean square error (RMSE), Akaike’s information criterion (AIC), Bayesian information criterion (BIC), maximum and minimum predicted values, and the regression plot. Furthermore, other measures of model quality and graphical analysis of residuals are also included. The package can be downloaded from the CRAN repository using the command: install.packages(“AgroReg”). AgroReg is a promising analysis tool in agricultural research on account of its user-friendly and straightforward functions that allow for fast and efficient data processing with greater reliability and relevant information.

Abstract The planting of new types of table citrus is an interesting alternative for citrus growers in the state of Paraná, as this domestic market continues to grow and needs innovation. Thus, the aim of this study was to evaluate the acceptance and storage of a new hybrid for the region of Londrina / PR, Fremont IAC 543 mandarin (Citrus clementina hort. ex Tan x C. reticulataBlanco). Treatments were: storage of fruits with and without wax coating at room temperature [21 ± 2 °C and relative humidity (RH) = 60 ± 5%] for up to 36 days. Sensory (acceptance test and purchase intention) and physicochemical analyses [weight, juice yield, acidity, soluble solids and soluble solids/titratable acidity (ratio)] were performed before and after storage. Physicochemical data were submitted to analysis of variance and regression, while sensory analysis results were explored through descriptive statistics and principal components analysis using the R statistical software. It could be concluded that Fremont IAC 543 mandarin can be stored with wax coating and at room temperature without losing its quality characteristics for a period of up to 18 days.

Deoxynivalenol (DON) is a predisposing factor for necrotic enteritis. This study aimed to investigate the effects of a DON and Clostridium perfringens (CP) challenge on the intestinal morphology, morphometry, oxidative stress, and immune response of broilers. Additionally, we evaluated the potential of a Lactobacillus spp. mixture as an approach to mitigate the damage induced by the challenge. One-day-old broiler chickens (n = 252) were divided into seven treatment groups: Control, DON, CP, CP + DON, VL (DON + CP + viable Lactobacillus spp. mixture), HIL (DON + CP + heat-inactivated Lactobacillus spp. mixture), and LCS (DON + CP + Lactobacillus spp. mixture culture supernatant). Macroscopic evaluation of the intestines revealed that the CP + DON group exhibited the highest lesion score, while the VL and HIL groups showed the lowest scores. Microscopically, all Lactobacillus spp. treatments mitigated the morphological changes induced by the challenge. DON increased levels of reactive oxygen species (ROS) in the jejunum, and CP increased ROS levels in the jejunum and ileum. Notably, the Lactobacillus spp. treatments did not improve the antioxidant defense against CP-induced oxidative stress. In summary, a Lactobacillus spp. mixture, whether used as a probiotic, paraprobiotic, or postbiotic, exerted a partially protective effect in mitigating most of the intestinal damage induced by DON and CP challenges.

Pomegranate fruit is to rich in phenolic compounds and antioxidant properties and can show difference in the composition according to cultivars, part of fruit, environmental conditions and analysis method. Therefore, the aim of the present study was to analyse and to compare the chemical composition and antioxidant properties from the different parts of fruit Valenciana and Wonderful pomegranate cultivars. The pomegranate fruits were separated into aril, peel, membrane and seeds manually and analysed by phenolic compounds, flavonoids, antioxidant activity (DPPH method), soluble solids, titratable acidity, pH and vitamin C content. The phenolic content and flavonoids were significantly affected by pomegranate cultivars and part of fruit. In the part of fruit showed differences by the DPPH, however the pomegranate cultivars not showed. Significant differences were revealed between the pomegranate cultivars and part of fruit for total soluble solids, titratable acidity and pH. The differents part of pomegranate fruit (aryl, membrane peeling and seed) has influences on the phenolic content, flavonoids, antioxidants, total soluble solids, pH and acidity. The cultivar does not show diffences on the antioxidants by DPPH method, pH and vitamin C.This study suggests the importance of the selection the different parts of fruit and cultivar that will be used as raw material in the preparation of pomegranate products with higher antioxidant activities.

Recent searches stress that soybean yield might be doubled in Brazilian conditions, so that base fertilization is pivotal, once it might interfere over the chemical and microbiological soil indicators and hence, over the crop grain yield. It was aimed to assess alterations in the chemical and microbiological soil indicators, in the short term, and the soybean biometric and grain yield performance as a function of different fertilizers for base fertilization, in two sowing dates. An experiment comprised of two sowing dates was carried out in 2019/2020 season on a dystroferic Red Latossol, in north Parana state. It were assessed five treatments comprising: 1) control; 2) mineral fertilizer; 3) organomineral fertilizer; 4) mineral fertilizer mixed to granulated gypsum; and 5) slow release mineral fertilizer. Randomized block design with four replicates was the design adopted. It were assessed chemical and microbiological soil indicators; final stand; first pod insertion height; plant height; stem diameter; number of pods per plant; number of grains per plant; number of grains per pod; grain mass per plant; one thousand grain mass and grain yield. There is no base fertilization effect over the chemical soil indicators in the short term, however, there is effect over the microbiological soil indicators. Biometric and grain yield performance are decreased as sowing date is delayed, regardless of the base fertilization employed.

O objetivo do presente trabalho foi cultivar a bromélia Neoregelia “Fireball” em diferentes intensidades luminosas para verificar a capacidade de aclimatação e a influência do ambiente nas características morfoagronômicas da espécie. O experimento foi conduzido durante cinco meses em 2019 na Universidade Estadual de Londrina, nos tratamentos 0, 30, 50, 70 e 80% de sombreamento. Foi possível observar que, apesar de serem cultivas em ambientes diferentes, as plantas não apresentaram diferença estatística nos parâmetros analisados, além disso essas bromélias apresentaram um incrível comportamento de plasticidade vegetal aclimatando-se aos ambientes, sobrevivendo e se reproduzindo possibilitando a garantia de produtividade em caso de utilização destes tratamentos em um empreendimento de cunho comercial.

ABSTRACT Heavy clayey Ferralsols are known for their high capacity to form water-stable macroaggregates. However, little is known about how different size classes of macroaggregates exchange mass with increasing organic matter content. This study aimed to characterize and detail aggregation dynamics with increasing organic matter content in these soils. Profiles of three heavy clayey Ferralsols were sampled to isolate the role of organic matter on the stability of aggregates. In this sampling scenario, a conceptual model was established to calculate the aggregation rate of different size classes of water-stable aggregates. This approach allowed the establishment of a critical value for classifying microaggregates in the studied soils (≤0.50 mm) based on their behavior as “building blocks” for macroaggregates when organic matter content is increased. In surface soil layers, where organic matter is higher, most dynamics are expected to happen between macroaggregates classes because free microaggregates are scarce. Consequently, it is important to subdivide macroaggregates into different size classes when evaluating their stability. Quantifying macroaggregates as a single class (e.g., >0.25 or >0.50 mm) was insufficient in representing the macroaggregation dynamics in heavy clayey Ferralsols.

Bauhinia monandra Kurz has ornamental characteristics as the shape of its crown and the exuberance of its flowering, being and is widely cultivated in urban afforestation in Brazilian regions. The production of forest seedlings is essential not only to meet the demand of urban afforestation, but also to conserve forests. However, studies on B. monandra regarding the degree of fruit maturity on seed performance are scarce. Thus, the objective of the current work was to verify the germination potential of B. monandra seeds at different stages of maturation at five constant temperatures. The germination percentage, germination speed index (GSI), mean germination time (t), relative germination frequency, and mean germination speed (MGS) were evaluated. Initially, the mature seeds had a water content of 8.5% and the immature seeds of 68.3%. Mature seeds reached high germination percentages, above 96% for temperatures of 25, 30, and 35 ºC. The immature seeds demonstrated low germination percentages, reaching the highest percentage of 33% for the temperature of 25 ºC, followed by the temperatures of 30 ºC and 35 ºC, with respective percentages of 32% and 20%. Mature seeds demonstrated the highest GSI value (11.79) for the estimated temperature of 26.94 ºC and immature seeds the highest value of t (7.85) for the temperature of 26.56 ºC. It is concluded that mature seeds aggregate higher germination at an estimated temperature of 24.72 ºC and that immature seeds present unsatisfactory germination performance.

The main strawberry cultivars grown in tropical regions originated from breeding programs developed in temperate countries, which limit the expression of their maximum productive potential when grown in warm climates. Additionally, strawberry cultivation in these regions depends almost entirely on imported strawberry young plants, increasing production costs. Obtaining adapted cultivars with a lower requirement for the accumulation of chilling hours is the main objective of breeding programs in the southern hemisphere. Thus, the objective of this study was to evaluate short-day strawberry genotypes, pre-selected based on yield and fruit quality components through multivariate analysis, for cultivation in tropical conditions. Two experiments were performed. In the first one, 36 pre-selected genotypes and their parents were assessed based on productive traits (total fruit mass, commercial fruit mass, and mean mass of commercial fruits), soluble solids content, and fruit firmness. For selection, multivariate analysis was applied using the genotype (ideotype) selection index and principal component analysis. In the second experiment, the fruit of the best-ranked genotypes, the parents, and the Camarosa and Dover cultivars were assessed for soluble solids (SS), titratable acidity (TA), SS/TA ratio, ascorbic acid, phenolic compounds, and total anthocyanins. To identify the most promising genotypes, the data were analyzed using principal component analysis. The RVFS06CR-105, RVDA11CR-61, RVDA11CR-125, and RVCS44CR-130 were the most promising genotypes for cultivation in tropical conditions, based on yield and fruit quality components. The means found for these genotypes were higher than the commercial cultivars Dover, Camino Real, and Camarosa. The use of multivariate analysis was efficient in selecting the genotypes, with repeatability of information between the methods guaranteeing consistency in the information. The selected genotypes had higher yields than those used as the control, which is a promising result considering the independence in relation to genetic material, mainly in the expansion of the cultivation area in the tropical regions of the southern hemisphere. In addition, these genotypes are being evaluated in different tropical climate regions with the aim of validating them for submission to the registration and release process for farmers. Additionally, they are being used as a source of genes for crossings and new selections.

O manejo adequado da cobertura do solo para o cultivo de citros pode contribuir com o aumento da produtividade e melhoria da qualidade do solo. Esse trabalho estudou cinco diferentes coberturas vegetais (Urochloa brizantha; U. decumbens, U. ruziziensis, vegetação espontânea e aplicação de herbicida (glifosato) em área total) na entrelinha do pomar de laranjeira ‘Natal’ [Citrus sinensis (L.) Osbeck] enxertada em citrumeleiro ‘Swingle’ (C. paradisi × Poncirus trifoliata) nos atributos microbiológicos e químicos do solo, bem como a influência desse manejo no desenvolvimento vegetativo do pomar. Foram avaliados os atributos químicos (Ca2+, Mg2+, K+, P, pH, H+Al, CTCpH7 saturação por bases e MO) e microbiológicos (carbono e nitrogênio da biomassa microbiana, respiração basal e quociente metabólico) do solo na linha e na entrelinha do pomar, nos anos de 2018 e 2019. Houve diferença significativa para a maioria das variáveis nos dois anos estudados, com destaque no ano de 2019 para as variáveis microbiológicas e na MO, sendo esse último, 14,8% menor no tratamento com glifosato em área total em relação ao tratamento com vegetação espontânea. Os resultados permitiram evidenciar os benefícios da cobertura vegetal com as braquiárias na entrelinha do pomar de laranjeira doce ‘Natal’ nos atributos químicos e microbiológicos do solo, sobretudo no carbono e nitrogênio da biomassa microbiana.

A cor das bagas é um aspecto importante de qualidade e comercialização de uvas de mesa. A uva fina de mesa ‘Rubi’ produzida em clima subtropical geralmente apresenta deficiência de cor devido à inibição da formação de antocianinas pelas altas temperaturas durante a maturação. Um dos métodos utilizados para superar esse problema é a aplicação exógena de ácido abscísico (S-ABA), uma vez que o acúmulo de antocianinas na casca das bagas é controlado por esse regulador vegetal. O objetivo deste trabalho foi determinar o efeito da aplicação do S-ABA em diferentes fases de maturação no desenvolvimento da cor da uva fina de mesa ‘Rubi’, visando o incremento e uniformização da cor dos seus cachos, tendo como referência o teor de sólidos solúveis (SS) das bagas. O experimento foi avaliado em dois ensaios a campo, em pomares comerciais. O primeiro ensaio foi realizado em Marialva, Paraná, Brasil, durante a safra de verão (colheita em dezembro) de 2019. Os tratamentos foram constituídos da aplicação de S-ABA na concentração de 400 mg L-1, em diferentes fases de maturação da uva ‘Rubi’, de acordo com o teor de SS das bagas, assim descritos: controle (sem aplicação); SS = 8-9 ºBrix; SS = 10-11 ºBrix; SS = 8-9 ºBrix em duas aplicações, sendo a segunda realizada aos 10 dias após a primeira; e SS = 10-11 ºBrix, em duas aplicações, sendo a segunda realizada aos 10 dias após a primeira. O segundo ensaio foi realizado em Cambira, Paraná, Brasil, durante a safra temporona ou de outono (colheita em maio) de 2020. Os tratamentos foram constituídos da aplicação de S-ABA na concentração de 400 mg.L-1 em diferentes fases de maturação da uva ‘Rubi’, de acordo com o teor de SS das bagas, assim descritos: controle (sem aplicação); SS = 6-7 ºBrix; SS = 7-8 ºBrix; SS = 9-10 ºBrix; SS = 6-7 ºBrix em duas aplicações, sendo a segunda realizada aos 14 dias após a primeira; SS = 7-8 ºBrix em duas aplicações, sendo a segunda realizada aos 14 dias após a primeira; e SS = 9-10 ºBrix em duas aplicações, sendo a segunda realizada aos 14 dias após a primeira. O delineamento experimental de ambos experimentos foi em blocos casualizados com 4 repetições, sendo que cada parcela foi composta por uma videira. As variáveis analisadas foram antocianinas totais, índice de cor (CIRG), e atributos (L*, C*, h° e deltaE) das bagas. As avaliações quanto ao acúmulo de antocianinas totais e atributos de cor das bagas foram realizadas a cada 10 e 7 dias após a primeira aplicação do S-ABA até a colheita no primeiro e segundo experimento, respectivamente, e as demais variáveis foram avaliadas no momento da colheita. Na safra de verão, a aplicação do S-ABA quando o teor de SS era de 8-11 ºBrix aumentou significativamente a concentração de antocianinas totais das bagas, sendo 4 vezes maior que o controle, e também houve aumento do CIRG e de todos os atributos de cor. Na safra temporona, a aplicação do S-ABA também propiciou incrementos significativos sobre a concentração de antocianinas totais, sendo de 2 a 3 vezes maior que o controle, e para o CIRG e os atributos de cor também houve aumento quando o teor de SS era de 6-10 ºBrix. Nas duas safras avaliadas, uma única aplicação do regulador vegetal foi suficiente para intensificar a cor das bagas.

A produção de mudas florestais com qualidade e em quantidade é essencial para a restauração de ambientes outrora desmatados e degradados. Todavia, a obtenção de sementes com alto vigor é um desafio para diversas espécies arbóreas nativas do Brasil. O objetivo deste trabalho foi verificar o potencial germinativo de sementes de jatobá-da-mata em diferentes estádios de maturação, de modo a favorecer a produção de mudas dessa espécie em viveiros. As sementes foram extraídas de frutos verdes e maduros destacados da planta mãe e frutos maduros coletados no chão. Foram mensurados o percentual de germinação, o tempo médio de germinação, o índice de velocidade de emergência, a velocidade média, a frequência relativa, área foliar da plântula e comprimento de parte aérea e raiz. A semeadura foi realizada com sementes escarificadas mecanicamente e intactas de cada grupo de maturação. Os resultados indicaram que as sementes verdes não escarificadas podem ser utilizadas para semeadura e produção de mudas, por dispensarem tratamento pré-germinativo e possuírem percentual de germinação favorável (79%). Já as sementes de frutos colhidos no chão necessitaram de um método para superar a dormência tegumentar, como a escarificação mecânica, obtendo a germinação de 85%. As sementes de frutos maduros colhidos na matriz apresentaram maior vigor, com maior percentual de germinação (96 a 100%), maior índice de velocidade de emergência, menor tempo médio de germinação, plântulas com maior área foliar e maior comprimento de parte aérea.e maior comprimento aérea parte.

As estratégias de controle de formigas-cortadeiras têm sido realizadas principalmente com iscas granuladas, à base dos princípios ativos fipronil e sulfluramida, que são comumente revestidas por substâncias atrativas cítricas. O uso constante das mesmas e a falta de alternativas no mercado podem favorecer a percepção de tais substâncias pelas formigas, causando rejeição para forrageamento e consequente dificuldade do seu controle. Neste sentido, o objetivo do trabalho foi avaliar a mortalidade de formigas-cortadeiras dos gêneros Atta e Acromyrmex, submetidas a aplicação direta com pós secos, em laboratório. Como tratamento preliminar, utilizou-se: um talco antisséptico comercial e, posteriormente seus componentes, com potencial ação inseticida, isoladamente, sendo: ácido salicílico, enxofre, ácido bórico, óxido de zinco, além de um talco inerte (Quimidrol®), como testemunha. Para cada tratamento foram utilizadas 40 formigas (operárias) acondicionadas em poliestireno cristal transparente (Tipo Gerbox), que foram polvilhadas com auxílio de um saleiro, estando com atividade reduzida, devido a permanência em geladeira, previamente ao tratamento. As formigas foram mantidas em 25 ± 2°C, fotofase de 12 horas e a mortalidade acumulada foi observada a cada 24 horas, considerando-se formigas mortas aquelas que não conseguiam manter a posição natural do corpo, ou seja, mesmo formigas moribundas foram consideradas mortas, quando não exibiam reação, ao serem tocadas por um pincel. O talco antisséptico comercial, quando polvilhado sobre as formigas, causa mortalidade de 40%, em ambas as espécies, 24 horas após as aplicações. Estudos subsequentes dos componentes do referido produto comercial detectaram que o ácido salicílico, quando polvilhado tanto para Atta sexdens rubropilosa quanto para Acromyrmex crassispinus, causa mortalidade de 100% das operárias nas primeiras 24 horas. Esse resultado abre uma nova perspectiva de controle, com produto de baixo impacto ambiental, sinalizando uma alternativa de controle em ninhos a campo, podendo contribuir para o controle integrado de formigas.

Increasing phosphorus (P) use efficiency in agricultural systems is urgent and essential to significantly reduce the global demand for this nutrient. Applying phosphate-solubilizing and plant growth-promoting bacteria in the rhizosphere represents a strategy worthy of attention. In this context, the present work aimed to select and validate bacterial strains capable of solubilizing phosphorous and promoting maize growth, aiming to develop a microbial inoculant to be used in Brazilian agriculture. Bacterial strains from the maize rhizosphere were evaluated based on their ability to solubilize phosphate and produce indole acetic acid. Based on these characteristics, 24 strains were selected to be further evaluated under laboratory, greenhouse, and field conditions. Among the selected strains, four (I04, I12, I13, and I17) showed a high potential to increase maize root growth and shoot P content. Strains I13 (Ag87) and I17 (Ag94) were identified by genomic sequencing as Bacillus megaterium and Lysinibacillus sp., respectively. These strains presented superior yield increments relative to the control treatment with 30% P. In addition, combining Ag87 and Ag94 resulted in even higher yield gains, indicating a synergistic effect that could be harnessed in a commercial inoculant for Brazilian agriculture.

Miltonia flavescens is a species vulnerable to extinction, which justifies research on preservation methods. Cryopreservation in liquid nitrogen (LN) consists of maintaining biological material at a low-temperature (-196 °C). Thus, the aim of the experiment is to evaluate the influence of different cryoprotective solutions on cryopreservation in LN of the Brazilian orchid Miltonia flavescens seeds. The experiment was conducted in a completely randomized design (CRD), with eight treatments and six replications. The treatments were composed as follows: control; immersion in LN, no cryoprotectant adding; and immersion in LN, with the addition of cryoprotectants: sucrose 0,4 mol L-1; glycerol 2 mol L-1; protection by vitrification in solution (PVS)1; PVS2; PVS2 + 1% phloroglucinol, and PVS3. Except for the control treatment, which was kept in a freezer (10±2 °C), the others remained frozen for 15 days. After this period, the viability of the seeds was evaluated. These seeds were sown and, 30 days after germination, then the frequency of protocorm formation was verified. Before the cryopreservation, the seeds showed 75% viability and 9.5% water content. After cryopreservation, the seeds varied between 67 to 75% viability. However, treatment with glycerol 2 mol L-1 exhibited lower performance than the others (58%). The control treatment showed a higher percentage of protocorm formation (71%) followed by treatments PVS1 (63%), PVS2 (64%), and PVS2PHLO (66%). For the purpose of preserving Miltonia flavescens seeds in liquid nitrogen for a prolonged period, the treatments PVS1, PVS2, and PVS2PHLO proved to be viable and promising alternatives.

Abstract The pomegranate fruit exhibits medicinal properties due to the nutraceutical characteristics, especially of its peel. The objective of this study was to analyze the influence of different drying methods on the physicochemical and biochemical characteristics of the pomegranate peel. The experiment was conducted in a completely randomized design in subdivided plots: 4 (full sun [SUN], drying chamber [DC] at 60 ± 2 °C, cold chamber at 10 °C and 60% relative humidity (RH) [CC], solar dryer [SD]) × 2 (presence or absence of 1% ascorbic acid [AA]). The analyzed variables were mass loss, index of drying heterogeneity (IHD), Hue internal (LI, CI, HI) and external (LE, CE, HE) angles, as well as Chroma, of the peel, and finally, total phenolic compound (TCFT) and flavonoid (TFLA) content. DC treatment led to the shortest drying time, followed by SUN and SD treatments. A reduction in IHD was observed with respect to time, which was more pronounced in DC treatment. CC treatment produced a more positive response both for LI and LE. TCFT and TFLA content produced from DC treatment presented an interaction effect, which was reduced by the application of AA. On the other hand, dehydration without the application of AA in the drying chamber or in full sun resulted in the best responses in TCFT and TFLA content.

ABSTRACT: Studies showed that intercropping garlic reduced pests in strawberry field crops. However, influence of intercropping on yield was not tested. The objective of the study was to evaluate the strawberry pseudofruit and garlic bulb productions in monocropping and intercropping systems. Assessments of the yields and calculation of the land equivalent ratio, competition ratio and gross income were performed. The experiments were conducted in three areas (two open field and one greenhouse) in Londrina municipality. Treatments in the field experiments were garlic or strawberry in monocrops (controls), strawberry (S) + one garlic row (GR), S + 2GR or S + 3GR per plot. In the greenhouse experiment, plants were grown in pots with following treatments: garlic or strawberry in monocrops, 2S + 2 garlic plants per plot (GPP), 2S + 4GPP or 2S + 5GPP. Similar yields (garlic bulbs and strawberry pseudofruits) were observed among the treatments. Intercropping garlic among strawberry plants increased the land equivalent ratio. The intercrop land equivalent ratio index ranged from 1.34 to 2.55. An increasing in gross income were observed when increasing garlic plant densities in intercropping with strawberry. Results showed that intercropping garlic with strawberry increases land equivalent ratio and gross income. Production of strawberry pseudofruits and garlic bulbs were not influenced by intercropping systems compared to monocropping.