Revolutionary Role of Trichoderma in Sustainable Plant Health Management: A Review

The use of chemical pesticides in agricultural practices has led to significant concerns related to health and the environment in the last few decades. Consequently, there has been a growing interest in finding alternative approaches for controlling pests and diseases that are effective and environmentally friendly. Among these alternatives, Trichoderma harzianum has gained attention due to its remarkable ability to combat various crop pathogens in sustainable form. Biocontrol agents have gained prominence as eco-friendly substitutes for conventional chemical pesticides in disease management and crop improvement. T. harzianum, a common filamentous fungus, has emerged as a promising biocontrol agent due to its multifaceted strategies for suppressing diseases and promoting crop growth. T. harzianum fosters plant growth by aiding nutrient absorption, improving soil structure, and generating growth-promoting substances like auxins and cytokinins. Field studies have substantiated the efficacy of T. harzianum in managing a wide array of plant diseases caused by fungi, bacteria, and nematodes whether used as a seed treatment, soil application, or foliar spray, T. harzianum establishes a beneficial presence early in the plant's life cycle, providing enduring protection. In conclusion, T. harzianum holds immense potential as a biocontrol agent to sustainably safeguard crops. Trichoderma species play a pivotal role in managing plant diseases due to their versatile mechanisms. As global agriculture seeks alternatives to chemical pesticides, leveraging T. harzianum 's potential offers a valuable avenue toward resilient and environmentally safe crop production.

Trichoderma Species and Their Biological Mechanisms

Biocontrol agents (BCA) are an important tool for preventing crop losses and increasing plant food production in agriculture. Providing an eco-friendly and more sustainable alternative to chemical pesticides and fertilizers. A number of biocontrol applications are often conducted on the fungus Trichoderma, which is one of the most widely used and studied organisms in the field due to its numerous biocontrol traits, including parasitism, secondary metabolite production, antibiosis which induced plant defense mechanisms. It is well known that several Trichoderma species act as mycoparasites. Certain species within this group also possess the ability to oppose many organisms, including nematodes and plant pests, hence exhibiting their versatility as a biological control agent. The utilization of bioformulations incorporating Trichoderma species or other beneficial microbes for plants, such as plant growth-promoting bacteria (PGPB), has gained significant traction in the agricultural industry. The present review provides a comprehensive summary of the biocontrol studies conducted on six commonly utilized Trichoderma species. It focuses on elucidating their biocontrol attributes and explores the potential of incorporating these fungal genera into Trichoderma-based formulations for safeguarding against plant diseases. Furthermore, it discusses the viability of Trichoderma as a substitute for chemical pesticides and fertilizers.

Biocontrol Potential and Mechanism of Bacillus SPP. against Phytopathogens: A Review

The biocontrol potential of Bacillus spp. clearly indicated by several authors are presented crop wise. The understanding of mechanism of action of Bacillus spp. against phytopathogens is essential to support their biocontrol potential. In this regard the various mechanism of action of Bacillus is elaborately discussed with suitable subheadings along with their plant growth promoting ability. The available literature presented below as review strongly emphasized their distinct biocontrol potential coupled with plant growth promoting effect through their various behavioral, biological, biochemical, induction of resistance, role of antimicrobial peptide genes etc.

Silicon as resistance inducer to control black apphid Aphis craccivora Koch, 1854 in cowpea beans [Vigna unguiculata (L)] Walp

The black aphid Aphis craccivora (Koch, 1854) stands out between the bugs considered cowpea pests. The objective of this study was to evaluate the effects of silicon application on the resistance induction of cowpea plants to the black aphid A. craccivora. The experiment was conducted in the Entomology Laboratory of the Phytosanitary sector of the Centro de Ciências Agrárias at the Universidade Federal do Piauí. The effects of the application of silicon on biological aspects were evaluated using a completely randomized design, with four treatments and 40 repetitions, being: silicon in soil (T1), silicon in soil + leaf (T2), silicone leaf (T3), and control (T4). The following biological variables were evaluated: generation period, reproductive period, fecundity, and daily average of nymphs per female. The silicon and lignin contents were also evaluated in the plants. The silicic acid was applied in a 1% solution around the stem of the plants (soil), 15 days after emergence, by diluting 2 g of the product in 200 mL of water. However, the leaf application was carried out with sprayer five days after application in soil. The non-preference of A. craccivora on bean was also evaluated. The evaluations were performed after 24, 48 and 72 hours of infestation by counting nymphs at 24, 48 and 72 hours and adults at each leaf session. The application of silicon promotes the reduction of the production of nymphs, interfering in the biological aspects of A. craccivora, and has potential to be used in a cowpea pest management program in cowpea.

Biological control in the germination of seeds from two species native of the Cerrado region / Controle biológico na germinação de sementes de duas espécies nativas da região do Cerrado

Abstract Microorganisms have been efficiently used for the biological control of phytopathogens through the production of antimicrobial substances. However, the objectives of this work were: to study the germination of Butia purpurascens Glassman and Butia archeri Glassman seeds in different substrates, to select and identify the endophytic and rhizospheric bacterial isolates of B. purpurascens and B. archeri, and to perform antibiosis tests based on the isolated microorganisms of these tree species. No difference was found between the cultivation substrates for the percentages of germination, hard seeds, and fungal contamination in the B. purpurascens seeds. The Bacillus subtilis isolated showed the best capacity for suppressing the growth of the two deteriorative fungi tested in B. purpurascens seeds. No difference was found for inhibition of the growth of Aspergillus niger fungus (deteriorative fungus of B. archeri seeds) between the microorganisms with Bacillus sp. and Brevibacillus brevis compared to the control. In the microbiolization of B. purpurascens and B. archeri seeds performed with microbiological solutions produced from the endophytic and rhizospheric strains of Bacillus sp., no differences were observed in the percentages of germination and contamination by fungi. For B. archeri seeds, there was contamination by fungi and bacteria after one day of cultivation, primarily in the regions with lesions caused by the extraction and scarification process.

Resumo Microorganismos específicos tem sido usados eficientemente para o controle biológico de fitopatógenos através da produção de substâncias antimicrobianas. Portanto, os objetivos deste estudo foram: estudar a germinação de sementes de Butia purpurascens Glassman e Butia archeri Glassman em diferentes substratos; selecionar e identificar isolados bacterianos rizosféricos e endofíticos de B. purpurascens e B. archeri, e realizar testes de antibiose a partir de microorganismos isolados dessas espécies arbóreas. Não houve diferença entre os substratos de cultivo para as porcentagens de germinação, de sementes duras e de contaminação por fungos nas sementes de B. purpurascens. O isolado bacteriano Bacillus subtilis apresentou melhor capacidade de supressão do crescimento dos dois fungos deterioradores testados nas sementes de B. purpurascens. Não foi encontrada diferença para a inibição do crescimento do fungo Aspergillus niger (fungo deteriorador de sementes de B. archeri) entre os microorganismos com Bacillus sp. e Brevibacillus brevis em comparação ao controle. Na microbiolização das sementes de B. purpurascens e B. archeri realizada com soluções microbiológicas produzidas a partir de cepas endofíticas e rizosféricas de Bacillus sp. não foram observadas diferenças na porcentagem de germinação e contaminação por fungos. Para B. archeri houve contaminação por fungos e bactérias após um dia de cultivo, principalmente nas regiões de lesão proporcionadas pelo processo de extração e escarificação.

Resistance of rice genotypes to fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae)

ABSTRACT The fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is an important rice pest which consumes leaf area during all phases of plant development. The objective of this study was to identify rice genotypes that provide antixenosis and antibiosis to fall armyworm. Antixenosis was investigated by measuring non-preference in free-choice and no-choice tests while antibiosis was determined by measuring biological parameters and nutritional indices of S. frugiperda in twelve rice genotypes. The genotype Miúdo Branco showed antixenosis to S. frugiperda, whereas the genotypes IR 64 and Bacaba Branco showed antibiosis to S. frugiperda by affecting insect development and prolonging insect life cycle. Insects that fed on Bacaba Branco genotype demonstrated the lowest nutritional indices. Since Miúdo Branco, IR 64 and Bacaba Branco showed moderate resistance, rice producers could use these genotypes as part of a control strategy for S. frugiperda.

Population parameters as a way to evaluate the risk of attack of Aphis craccivora (Hemiptera: Aphididae) on cowpea / Parâmetros populacionais como forma de avaliar os riscos de ataque de Aphis craccivora (Hemiptera: Aphididae) em feijão-caupi

The objective of this research was to develop fertility life tables in order to estimate the population parameters of black aphid (Aphis craccivora Koch) in cowpea (Vigna unguiculata) varieties, aiming to propose a risk scale for its use. The experiment consisted of six treatments and six replicates (five varieties plus the cultivar VITA 7 as a susceptible control). A cohort was formed with six adult females distributed in six replicates of each genotype, and the insects were observed daily. Based on the data, fertility life tables were drawn for each variety and the population parameters were estimated. The different values of the finite growth rate (λ) were considered to propose a risk scale for the use of the genotypes. The results obtained give the dimension of the variability of V. unguiculata in respect to the character, resistance to A. craccivora, with antibiosis as the main mechanism of resistance. Considering all the results, the varieties studied can be classified according to their suitability as a plant favorable to the development of the black aphid as follows: VITA 7 > CE-13 > CE-51 > CE-08 = CE-07. The proposal of a risk scale for the use of V. unguiculata genotypes against the A. craccivora population, based on the finite growth rate (λ) values, was adequate to discriminate the varieties studied.(AU)

Objetivou-se nesta pesquisa elaborar tabelas de vida de fertilidade com o intuito de estimar os parâmetros populacionais de pulgão-preto (Aphis craccivora Koch) em variedades de feijão-caupi (Vigna unguiculata), visando propor uma escala de risco para o seu uso. O experimento constituiu-se em seis tratamentos (cinco variedades mais o cultivar VITA 7 como padrão de suscetibilidade) com seis repetições. Formou-se uma coorte com seis fêmeas adultas distribuídas em cada genótipo, sendo todos os indivíduos observados diariamente. De posse dos dados, foram elaboradas tabelas de vida de fertilidade para cada variedade e estimados os parâmetros populacionais. Para propor uma escala de risco de uso de genótipos, ponderou-se sob os diferentes valores da razão finita de crescimento (λ). Os resultados obtidos dão a dimensão da variabilidade de V. unguiculata com relação ao caráter da resistência a A. craccivora, sendo a antibiose o principal mecanismo de resistência associado. Considerando-se todos os resultados, foi possível hierarquizar as variedades estudadas segundo sua aptidão como planta favorável ao desenvolvimento ao pulgão-preto conforme segue: VITA 7 >> CE-13 > CE-51 > CE-08 = CE-07. A proposta de uma escala de risco do uso de genótipos de V. unguiculata frente à população de A. craccivora, baseada nos valores da razão finita de crescimento (λ), foi adequada para discriminar as variedades estudadas.(AU)

Preference of red mite Tetranychus ludeni Zacher (Acari: Tetranychidae) to sweet potato genotypes / Preferência do ácaro vermelho Tetranychus ludeni Zacher (Acari: Tetranychidae) por genótipos de batata-doce

Abstract Tetranychus ludeni damages the sweet potato. Pest development can vary between plant genotypes. The objective was to identify the preference of Tetranychus ludeni for Ipomoea batatas genotypes, from the germplasm bank at the Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM). Natural infestations of this mite were observed on 54 sweet potato genotypes in potted, in a greenhouse. Three mite-infested leafs of each genotype were collected and analyzed. The red mite showed different population density rate in genotypes. The BD 29 genotype was found to be highly susceptible, the BD 08, BD 57, BD 17 and Espanhola genotypes were moderately susceptible, and the others forty-nine genotypes showed low susceptibility to the mite.

Resumo Tetranychus ludeni danifica plantas de batata-doce. O desenvolvimento de pragas pode variar entre genótipos de plantas. O objetivo foi identificar a preferência de T. ludeni para genótipos de Ipomoea batatas do banco de germoplasma da Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM). Infestações naturais deste ácaro foram observadas em 54 genótipos de batata doce plantados em vasos e mantidos em estufa. Três folhas infestadas por ácaros, de cada genótipo, foram coletadas e analisadas. Tetranychus ludeni mostrou diferentes taxas de crescimento populacional entres os genótipos. O genótipo BD 29 foi altamente suscetível, os BD 08, BD 57, BD 17 e Espanhola foram moderadamente suscetíveis e os outros 49 genótipos mostraram baixa suscetibilidade ao ácaro.

Research progress on pharmacological action and new dosage forms of baicalin / 中草药

Baicalin is a kind of flavonoids derived from Scutellaria baicalensis with obvious pharmacological activities. Studies have shown that baicalin can be used in the treatment of pneumonia, tumor and hepatitis and other diseases. However, the poor water solubility and liposolubility of baicalin lead to the low bioavailability of it, which limits the clinical efficacy of baicalin. Therefore, in recent years, new dosage forms of baicalin have been prepared by new technology to improve its physical properties. Based on this, this paper reviews the research progress of pharmacological action and new dosage forms of baicalin based on the relevant literatures at home and abroad, in order to provide reference for the application and research of baicalin.

Research progress on anti-infective, anti-inflammatory, and anti-oxidant activities of myricetin / 中草药

Myricetin is a kind of flavonoids widely existing in Myrica rubra and many other plants. Myricetin has lots of biological functions, such as antitumor, reducing blood sugar and lipid, protecting cardiovascular system, and reducing nervous injury. In recent years, people pay more attention to the antibacterial, antiviral, anti-inflammatory, anti-oxidant, and immunosuppressive activities of myricetin. This paper reviews the literatures on the pharmacological activities of myricetin in recent years at home and abroad and focuses on its effects and molecular mechanism of anti-infective, anti-inflammatory, immunoregulatory and anti-oxidation activities, in order to provide the evidences for developing new drugs.

Silicon as resistance inducer in to control black aphid Aphis craccivora Koch, 1854 in Phaseolus lunatus lima beans / Silício como indutor de resistência no controle do pulgão preto Aphis craccivora Koch, 1854 em fava Phaseolus lunatus

In Brazil, there are few records of insects associated with the cultivation of lima beans; among them, there is the black aphid Aphis craccivora Koch, 1854. The objective of this study was to evaluate the effects of silicon application on the resistance induction of lima bean plants, Phaseolus lunatus, to the black aphid A. craccivora. The experiment was conducted in the Entomology Laboratory of the Phytosanitary Sector of Centro de Ciências Agrárias, Universidade Federal do Piauí (UFPI), Brazil. The effects of the following treatments on biological aspects of the insect were evaluated: silicon applied to soil; silicon applied to soil + leaf; silicon applied to leaf; and control, without silicon application. The following biological variables were evaluated: generation period, reproductive period, and the fertility and daily average of produced nymphs per female. Plant silicon and lignin content were also evaluated. A 1% solution of silicic acid (2.0 g of product diluted in 200 mL of water) was applied around the plant stem (on soil), 15 days after emergence. Leaf application was performed with a 1-L spray, 5 days after the soil application. The non-preference of A. craccivora on lima beans was also evaluated. The evaluations were performed after 48 and 72 hours of infestation by counting nymphs and adults at each leaf section. Silicon application reduces nymph production, thereby interfering in the biological aspects of A. craccivora. Therefore, it can be used in cowpea pest management programs.(AU)

São poucos os registros no Brasil de insetos associados à cultura da fava; entre eles, destaca-se o pulgão preto Aphis craccivora Koch, 1854. O objetivo deste estudo foi avaliar os efeitos da aplicação de silício na indução de resistência de plantas de feijão-fava Phaseolus lunatus a esse inseto. O experimento foi conduzido no Laboratório de Entomologia do setor de Fitossanidade do Centro de Ciências Agrárias da Universidade Federal do Piauí (UFPI). Os efeitos da aplicação do silício sobre os aspectos biológicos do inseto foram avaliados utilizando os tratamentos: silício aplicado no solo, silício aplicado no solo + folha, silício aplicado à folha; e controle, sem aplicação de silício. Foram avaliadas as variáveis biológicas: duração do período pré-reprodutivo, período reprodutivo e fertilidade, e média diárias de ninfas produzidas por fêmea. Os teores de silício e de lignina nas plantas também foram avaliados. O ácido silícico foi aplicado em uma solução a 1% ao redor do caule das plantas (no solo), 15 dias após a emergência, diluindo-se 2,0 g do produto em 200 mL de água. Já a aplicação foliar foi realizada com um pulverizador de 1 L, 5 dias após a aplicação em solo. A não preferência de A. craccivora em feijão também foi avaliada. As avaliações foram realizadas após 48 e 72 horas da infestação, por meio da contagem de ninfas e adultos em cada secção foliar. A aplicação de silício promove a redução da produção de ninfas, interferindo nos aspectos biológicos de A. craccivora, podendo ser utilizado em programas de manejo de pragas do feijão-fava.(AU)

Preparation of resveratrol-DPPC liposomal dry powder inhalations and its antibacterial activities / 中草药

Objective To prepare the resveratrol-DPPC liposomal dry powder inhalations (RDLDPIs), and solve the problem of lower bioavailability of resveratrol after oral administration. Methods The RDLDPIs were prepared by film-dispersion and freeze drying. The formulation was optimized by orthogonal design. The particle size, entrapment efficiency, electric potential, in vitro release, and lung deposition were characterized. The broth microdilution method was used to evaluate the antibacterial activity and determine the minimal inhibitory concentration (MIC) in vitro. Results The optimized ratio of DPPC/cholesterol, resveratrol/DPPC, and mannitol/DPPC was 3:1, 1:3, and 2:1 in the prescription of RDLDPIs, respectively; And hydration time was 15 min. The entrapment efficiency of RDLDPIs was (69.8 ± 1.6)%, the drug loading was (2.4 ± 0.9)%, the particle size was (191.5 ± 4.5) nm, and the zeta potential was (12.4 ± 1.5) mV. The aerodynamic particle size of the powder was (3.2 ± 0.2) μm and the in vitro pulmonary deposition ratio was 28.1% in vitro. The antibacterial activity against Staphylococcus aureus, Acinetobacter baumannii, Streptococcus pneumoniae, and Pseudomonas aeruginosa was evaluated in vitro. The crude drug group had no antibacterial activity in four species of bacteria, while RDLDPIs had antibacterial activity of Staphylococcus aureus and Acinetobacter baumannii, and MIC was 4 mg/mL and 2 mg/mL, respectively. Conclusion The prepared RDLDPIs have small size and uniform distribution with good stability and high lung deposition rate and in vitro antibacterial activity against Staphylococcus aureus and Acinetobacter baumannii, which is expected to be an substitute for traditional antibiotics for the treatment of bacterial pneumonia.

Research progress of pharmacological active substances from diazotrophic cyanobacteria / 中草药

As cyanobacteria with nitrogen-fixing ability, diazotrophic cyanobacteria can adapt to all kinds of habitat and produce many primary and secondary metabolic materials with unique chemical structures, diverse properties, and biological activities. As a nutritional supplement, diazotrophic cyanobacterium such as Nostoc has a long edible history in indigenous populations in China. In recent years, research results have shown that the bioactive substances produced by nitrogen-fixing cyanobacteria are promising candidates for the prevention and control of some human diseases, and the mechanisms of nitrogen-fixing cyanobacteria to achieve health and disease prevention are gradually revealed. This paper reviewed the progress in research and its mechanism of nitrogen-fixing cyanobacteria in anti-oxidation, scavenging free radicals, antibiosis, antivirus, antitumor, antiinflammation, and anticoagulation in the past five years (2013-2017) at home and abroad. Moreover, the existing problems and the development directions in future were also discussed. We expect that it can provide reference for the further development of the related field in China.

Research progress on Atractylodes japonica / 中草药

Objective Atractylodes japonica, a member of the Compositae family, is a per nnial Chinese medicinal plant, whose rhizomes are used as medicinal materials with functions of antibiosis, anti-inflammatory, and dispelling wind-cold. A. japonica is mainly distributed in northeast China, which is the genuine medicine in northeast China, and it is also a traditional medicine of Korean nationality. In this paper, the plant morphology, classification, identification of medicinal properties, chemical composition, pharmacological effects, and the cultivation techniques of A. japonica were briefly reviewed. The purpose of this paper is to provide theoretical reference for rational exploitation of Chinese material medica and sustainable utilization of resources of A. japonica.

Research progress on flavonoids and coumarins from Chimonanthus plants and its pharmacological activities / 中草药

Chimonanthus plants are endemic in China, which was rich and widely distributed; And its roots, stems, leaves, buds, and fruit can be used as medicine. It is a traditional garden flower and folk medicine, which has a great prospect for development. In this paper, the constituents flavonoids and coumarins from the genus Chimonanthus plants and its pharmacological activities were systematically reviewed, and their research status and development prospects were prospected to provide reference for the further research and development of Chimonanthus plants.

Popcorn genotypes resistance to fall armyworm / Genótipos de milho pipoca resistentes à lagarta-do-cartucho

ABSTRACT: The aim of this study was to evaluate popcorn genotypes for resistance to the fall armyworm, Spodoptera frugiperda. The experiment used a completely randomized design with 30 replicates. The popcorn genotypes Aelton, Arzm 05 083, Beija-Flor, Colombiana, Composto Chico, Composto Gaúcha, Márcia, Mateus, Ufvm Barão Viçosa, Vanin, and Viviane were evaluated,along with the common maize variety Zapalote Chico. Newly hatched fall armyworm larvae were individually assessed with regard to biological development and consumption of food. The data were subjected to multivariate analyses of variance and genetic divergence among genotypes was evaluated through the clustering methods of Tocher based on generalized Mahalanobis distances and canonical variable analyses. Seven popcorn genotypes, namely, Aelton, Arzm 05 083, Composto Chico, Composto Gaúcha, Márcia, Mateus, and Viviane,were shown to form a cluster (cluster I) that had antibiosis as the mechanism of resistance to the pest. Cluster I genotypes and the Zapalote Chico genotype could be used for stacking genes for antibiosis and non-preference resistance.

RESUMO: O objetivo do estudo foi avaliar genótipos de milho pipoca para resistência à lagarta-do-cartucho, Spodoptera frugiperda. O experimento foi conduzido em delineamento inteiramente casualizado com 30 repetições. Foram avaliados os genótipos de milho pipoca Aelton, Arzm 05 083, Beija-Flor, Colombiana, Composto Chico, Composto Gaúcha, Márcia, Mateus, Ufvm Barão Viçosa, Vanin, Viviane e Zapalote Chico. Larvas recém-eclodidas foram individualizadas para avaliação do desenvolvimento biológico e consumo alimentar. Os dados foram submetidos à análise multivariada de variância e a divergência genética entre genótipos foi avaliada através dos métodos de agrupamento de Tocher, com base na distância generalizada de Mahalanobis e análise de variáveis canônicas. Sete genótipos,Aelton, Arzm 05 083, Composto Chico, CompostoGaúcha, Márcia, Mateus e Viviane formaram um cluster (cluster I) que apresentaram antibiose com o mecanismo de resistência à praga. Os genótipos do cluster I e Zapalote Chico podem ser usados para empilhar genes para resistência por antibiose e não-preferência.

Atividade antimicrobiana in vitro dos extratos aquosos, hidroalcoólicos e alcoólicos das folhas de espécies da família Myrtaceae frente à cepas de bactérias de interesse / Antimicrobial activity in vitro of aqueous extracts, hydroalcoholic and spirits of Myrtaceae family species leaves front of the strains of interest of bacteria

Introdução: a Organização Mundial da Saúde (OMS) tem incentivado o estudo de plantas tradicionalmente conhecidas como medicinais, tendo como objetivo avaliar cientificamente os benefícios da utilização de medicamentos fitoterápicos e de conhecer, ao mesmo tempo, a segurança de seu uso indevido. Objetivos: este trabalho teve como objetivo avaliar a atividade antimicrobiana do extrato aquoso, hidroalcoólico e alcoólico de folhas de espécies da família Myrtaceae frente às cepas de bactérias de interesse. Metodologia: a análise da atividade antibacteriana dos extratos das folhas das plantas, jambo, azeitona preta, pitanga e goiaba foram verificados a partir do teste de difusão em Ágar Mueller-Hinton. As cepas utilizadas, após reativação, foram diluídas em solução salina estéril a 0,85%. Sendo consideradas com potencial antimicrobiano aqueles extratos que geraram halos ≥ 7 mm (sete milímetros). Resultados: os resultados encontrados na análise dos dados do extrato aquoso demonstraram que Eugenia uniflora, Syzygium cumini e Psidium guajava apresentaram atividade antimicrobiana sobre Staphylococcus aureus, na concentração de 100 mg/mL. Na análise dos dados dos extratos hidroalcoólico, Syzygium cumini demonstrou atividade antimicrobiana na concentração de 100 mg/mL sobre Pseudomonas aeruginosa, diante de Staphylococcus aureus, Eugenia uniflora, Syzygium malaccense, Syzygium cumini e Psidium guajava demonstraram atividade na concentração de 100 mg/mL cada. Observando os resultados dos extratos alcoólicos, Psidium guajava e Syzygium cumini demonstraram atividade antimicrobiana diante das quatro cepas estudadas. Conclusão: o presente estudo demonstrou que os extratos alcoólicos das espécies em estudo apresentaram melhor atividade antimicrobiana e maior espectro de ação quando comparado ao extrato aquoso e hidroalcoólico.

Introduction: this study aimed to evaluate the antimicrobial activity of aqueous extract, hydro-alcoholic and alcoholic leaf front Myrtaceae family species to strains of bacteria of interest. Objective: this study aimed to evaluate the antimicrobial activity of aqueous extract, hydro alcoholic and alcoholic leaves Myrtaceae front family species to strains of bacteria of interest. Methodology: the antibacterial activity of plant leaves extracts, rose apple, black olive, cherry and guava were verified from the diffusion test on Mueller-Hinton agar. Where the strains used after reactivation were diluted in 0.85% sterile saline. Being considered with antimicrobial potential that statement that generated halos ≥ 7 mm (seven millimeters). Results: the results of the analysis of the aqueous extract data demonstrated that Eugenia uniflora, Syzygium cumini and Psidium guajava showed antimicrobial activity against Staphylococcus aureus at a concentration of 100 mg/mL. In the data analysis of hydro-alcoholic extracts, Syzygium cumini demonstrated antimicrobial activity at a concentration of 100 mg/mL of Pseudomonas aeruginosa, before Staphylococcus aureus, Eugenia uniflora, Syzygium malaccense, Syzygium cumini and Psidium guajava showed activity at a concentration of 100 mg/mL each. Noting the results of alcoholic extracts, Psidium guajava and Syzygium cumini demonstrated antimicrobial activity against the four strains studied. Conclusion: the present study demonstrated that the alcoholic extracts of the species under study presented better antimicrobial activity and a greater spectrum of action when compared to the aqueous and hydroalcoholic extract.

Bacterial selection for biological control of plant disease: criterion determination and validation

Abstract This study aimed to evaluate the biocontrol potential of bacteria isolated from different plant species and soils. The production of compounds related to phytopathogen biocontrol and/or promotion of plant growth in bacterial isolates was evaluated by measuring the production of antimicrobial compounds (ammonia and antibiosis) and hydrolytic enzymes (amylases, lipases, proteases, and chitinases) and phosphate solubilization. Of the 1219 bacterial isolates, 92% produced one or more of the eight compounds evaluated, but only 1% of the isolates produced all the compounds. Proteolytic activity was most frequently observed among the bacterial isolates. Among the compounds which often determine the success of biocontrol, 43% produced compounds which inhibit mycelial growth of Monilinia fructicola, but only 11% hydrolyzed chitin. Bacteria from different plant species (rhizosphere or phylloplane) exhibited differences in the ability to produce the compounds evaluated. Most bacterial isolates with biocontrol potential were isolated from rhizospheric soil. The most efficient bacteria (producing at least five compounds related to phytopathogen biocontrol and/or plant growth), 86 in total, were evaluated for their biocontrol potential by observing their ability to kill juvenile Mesocriconema xenoplax. Thus, we clearly observed that bacteria that produced more compounds related to phytopathogen biocontrol and/or plant growth had a higher efficacy for nematode biocontrol, which validated the selection strategy used.

Preference of red mite Tetranychus ludeni Zacher (Acari: Tetranychidae) to sweet potato genotypes

Abstract Tetranychus ludeni damages the sweet potato. Pest development can vary between plant genotypes. The objective was to identify the preference of Tetranychus ludeni for Ipomoea batatas genotypes, from the germplasm bank at the Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM). Natural infestations of this mite were observed on 54 sweet potato genotypes in potted, in a greenhouse. Three mite-infested leafs of each genotype were collected and analyzed. The red mite showed different population density rate in genotypes. The BD 29 genotype was found to be highly susceptible, the BD 08, BD 57, BD 17 and Espanhola genotypes were moderately susceptible, and the others forty-nine genotypes showed low susceptibility to the mite.

Resumo Tetranychus ludeni danifica plantas de batata-doce. O desenvolvimento de pragas pode variar entre genótipos de plantas. O objetivo foi identificar a preferência de T. ludeni para genótipos de Ipomoea batatas do banco de germoplasma da Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM). Infestações naturais deste ácaro foram observadas em 54 genótipos de batata doce plantados em vasos e mantidos em estufa. Três folhas infestadas por ácaros, de cada genótipo, foram coletadas e analisadas. Tetranychus ludeni mostrou diferentes taxas de crescimento populacional entres os genótipos. O genótipo BD 29 foi altamente suscetível, os BD 08, BD 57, BD 17 e Espanhola foram moderadamente suscetíveis e os outros 49 genótipos mostraram baixa suscetibilidade ao ácaro.

Biological control in the germination of seeds from two species native of the Cerrado region

Abstract Microorganisms have been efficiently used for the biological control of phytopathogens through the production of antimicrobial substances. However, the objectives of this work were: to study the germination of Butia purpurascens Glassman and Butia archeri Glassman seeds in different substrates, to select and identify the endophytic and rhizospheric bacterial isolates of B. purpurascens and B. archeri, and to perform antibiosis tests based on the isolated microorganisms of these tree species. No difference was found between the cultivation substrates for the percentages of germination, hard seeds, and fungal contamination in the B. purpurascens seeds. The Bacillus subtilis isolated showed the best capacity for suppressing the growth of the two deteriorative fungi tested in B. purpurascens seeds. No difference was found for inhibition of the growth of Aspergillus niger fungus (deteriorative fungus of B. archeri seeds) between the microorganisms with Bacillus sp. and Brevibacillus brevis compared to the control. In the microbiolization of B. purpurascens and B. archeri seeds performed with microbiological solutions produced from the endophytic and rhizospheric strains of Bacillus sp., no differences were observed in the percentages of germination and contamination by fungi. For B. archeri seeds, there was contamination by fungi and bacteria after one day of cultivation, primarily in the regions with lesions caused by the extraction and scarification process.

Resumo Microorganismos específicos tem sido usados eficientemente para o controle biológico de fitopatógenos através da produção de substâncias antimicrobianas. Portanto, os objetivos deste estudo foram: estudar a germinação de sementes de Butia purpurascens Glassman e Butia archeri Glassman em diferentes substratos; selecionar e identificar isolados bacterianos rizosféricos e endofíticos de B. purpurascens e B. archeri, e realizar testes de antibiose a partir de microorganismos isolados dessas espécies arbóreas. Não houve diferença entre os substratos de cultivo para as porcentagens de germinação, de sementes duras e de contaminação por fungos nas sementes de B. purpurascens. O isolado bacteriano Bacillus subtilis apresentou melhor capacidade de supressão do crescimento dos dois fungos deterioradores testados nas sementes de B. purpurascens. Não foi encontrada diferença para a inibição do crescimento do fungo Aspergillus niger (fungo deteriorador de sementes de B. archeri) entre os microorganismos com Bacillus sp. e Brevibacillus brevis em comparação ao controle. Na microbiolização das sementes de B. purpurascens e B. archeri realizada com soluções microbiológicas produzidas a partir de cepas endofíticas e rizosféricas de Bacillus sp. não foram observadas diferenças na porcentagem de germinação e contaminação por fungos. Para B. archeri houve contaminação por fungos e bactérias após um dia de cultivo, principalmente nas regiões de lesão proporcionadas pelo processo de extração e escarificação.