Bioagents and mix of cover plants affecting soybean / Bioagentes e mix de plantas de cobertura afetando a soja

The search for cultivation practices that provide productive, social and environmental benefits to the agroecosystem isof great importance for the sustainable intensification of agriculture. The objective of this study was to determine the effect of multifunctional microorganisms (MM) and mix of cover crops on gas exchange, production components and grain yield of soybean. In the field experiment, conducted by two growing seasons, the experimental design of randomized blocks in factorial scheme 8x2 was used, with four replications. The treatments were composed by the combination of eight vegetal cover and the use or not of MM. The vegetal cover were composed of: 1. Fallow, 2. Corn, 3. Mix 1 (white lupine, buckwheat, white oats, black oats, Crotalaria ochroleuca, C. juncea, turnip, coracana grass, white lupine), 4. Mix 2 (millet, C. ochroleuca, black oats, white oats, buckwheat, coracana grass), 5. Mix 3 (Millet, C. ochroleuca, black oats, white oats, buckwheat, coracana grass), 6. Mix 4 (C. spectabilis, buckwheat, millet and C. breviflora), 7. Mix 5 (oats, buckwheat, millet, piatã grass and C. Ocholeuca); and 8. Mix 6. (black oats, turnip forage, white lupine, coracana grass, buckwheat). The MM consortium used was Serratia marcenses(BRM 32114) + Bacillus sp.(BRM 63573). Soybean plants coinoculated with (BRM 32114) + (BRM 63573) showed an increase in photosynthetic rate (16.65%), stomatal conductance (37.50%), internal CO2concentration (10%), number of pods per plant (15%), mass of 100 grains (4.04%) and grain yield (14.83%). However, no differences were observed in soybean plants grown in succession to the mix of cover crops, except for the number of grains per pod. Therefore, in this study, the highlight was the consortium of multifunctional microorganisms, technology considered strategic for the sustainable intensification of agriculture.(AU)

A busca por práticas de cultivo que proporcionem benefícios produtivos, sociaiseambientaisao agroecossistemaé de grande importância para aintensificação sustentável da agricultura. O objetivo deste estudo foi determinar o efeito demicrorganismos multifuncionais (MM)emix de plantas decoberturasobre as trocas gasosas, componentes de produção e produtividadede grãosdasoja. Noexperimento de campo, conduzido por duas safras agrícolas,utilizou-se o delineamento experimental de blocos casualizados em esquema fatorial 8x2, com quatro repetições. Os tratamentos foram compostos pelacombinação de oito coberturas vegetaise do usoou não MM. As coberturasvegetais foram compostas de:1. Pousio; 2. Milho; 3. Mix 1 (Tremoço Branco, Trigo Mourisco, Aveia Branca, Aveia Preta, Crotalariaochroleuca, C.Juncea, Nabo Forrageiro, Capim coracana)4. Mix 2 (trigo Mourisco, C.spectabiliis, nabo forrageiro, aveia preta); 5. Mix 3 (Milheto, C. ochroleuca, aveia preta, aveia branca, trigo mourisco, Capim coracana); 6. Mix 4 (C. spectabilis, trigo mourisco, milheto e C.breviflora); 7. Mix 5 (Aveia, Trigo Mourisco, Milheto, Piatãe C.ocholeuca); e 8. Mix 6.(Aveia preta, Nabo Forrageiro, Tremoço Branco, Capim coracana, Trigo Mourisco). O consórciode MM utilizadofoi Serratiamarcenses(BRM 32114) + Bacillussp.(BRM63573). Plantas de soja coinoculadas com (BRM 32114) + (BRM63573)apresentaram aumento na taxa fotossintética (16,65%), condutância estomática (37,50%),concentração interna de CO2(10%), número de vagens por planta (15%),massa de 100 grãos (4,04%) e produtividade de grãos (14,83%). Contudo, não foram observadas diferenças nasplantas de soja cultivadasem sucessão aos mix de plantas de cobertura, com exceção do número de grãos por vagem.Portanto, nesse estudo, o destaque foi para o consórcio de microrganismos multifuncionais, tecnologiaconsideradaestratégica para a intensificação sustentável da agricultura.(AU)

Initial development of upland rice inoculated and co-inoculated with multifunctional rhizobacteria / Desenvolvimento inicial de arroz de terras altas inoculado e coinoculado com rizobactérias multifuncionais

Inoculation and co-inoculation of upland rice with multifunctional rhizobacteria can promote plant growth, especially the root system. Thus, this study aimed to evaluate the effect of inoculation and co-inoculation with Azospirillum sp. and Bacillus sp. in the early development of upland rice. The experiment was conducted using a completely randomized design with 4 treatments and 10 replications, totaling 40 plots. The treatments were: 1) Ab-V5 (Azospirillum brasilense), 2) BRM 63573 (Bacillus sp.), 3) co-inoculation of Ab-V5 + BRM 63573, and 4) control (without rhizobacteria). Inoculation and co-inoculation with the multifunctional rhizobacteria Ab-V5 and BRM 63573 provided positive effects on the initial development of upland rice. Inoculation with isolate BRM 63573 had significant effects on root length, shoot, and total biomass, while inoculation with isolate Ab-V5 had significant effects on root length and production of root and total biomass. Co-inoculation treatment had significant effects on variables such as diameter, volume, total surface, root biomass, and total biomass. The control treatment (without multifunctional rhizobacteria) had the worst results for most of the analyzed variables.

A inoculação e coinoculação do arroz de terras altas com rizobactérias multifuncionais pode promover o crescimento das plantas, especialmente do sistema radicular. Assim, este estudo teve como objetivo avaliar o efeito da inoculação e coinoculação com Azospirillum sp. e Bacillus sp. no desenvolvimento inicial do arroz de terras altas. O experimento foi conduzido em delineamento inteiramente casualizado com 4 tratamentos e 10 repetições, totalizando 40 parcelas. Os tratamentos foram: 1) Ab-V5 (Azospirillum brasilense), 2) BRM 63573 (Bacillus sp.), 3) coinoculação de Ab-V5 + BRM 63573 e 4) controle (sem rizobactérias). A inoculação e coinoculação com as rizobactérias multifuncionais Ab-V5 e BRM 63573 proporcionaram efeitos positivos no desenvolvimento inicial do arroz de terras altas. A inoculação com o isolado BRM 63573 teve efeitos significativos no comprimento da raiz, parte aérea e biomassa total, enquanto a inoculação com o isolado Ab-V5 teve efeitos significativos no comprimento da raiz e produção de raiz e biomassa total. O tratamento com coinoculação teve efeitos significativos em variáveis como diâmetro, volume e superfície total de raiz e biomassa de raiz e total. O tratamento controle (sem rizobactérias multifuncionais) apresentou os piores resultados para a maioria das variáveis analisadas.

Characterization of the antagonism of the mycorrhizal fungus Waitea circinata against Magnaporthe oryzae, Cochliobolus miyabeanus, Monographella albescens and Sarocladium oryzaerice pathogens / Caracterização do antagonismo do fungo micorrízico Waitea circinata contra os patógenos do arroz Magnaporthe oryzae, Cochliobolus miyabeanus, Monographella albescens e Sarocladium oryzae

Rice production is affected by important pathogens such as Magnaporthe oryzae, Cochliobolus miyabeanus, Monographella albescens and Sarocladium oryzae, and orchid mycorrhizal fungi can contribute to the biocontrol of these diseases. The aim of this study was to characterize the antagonism mechanisms of W. circinata against rice pathogens. The indoleacetic acid (IAA) and lytic enzymes of W. circinata were quantified. The effectiveness of the bioagent and its metabolites was assessed in vitro. Antagonism in vivo against rice blast was also investigated. Waitea circinata produced IAA (2.3 µg ml¹), cellulase and polyphenol oxidase in a qualitative test. Glucanase, chitinase and protease were also produced in culture with cell walls and in co-culture with pathogens to explain antibiosis. W. circinata acts on direct antagonism by antibiosis and volatile metabolites. Mycelial suspension reduced M. oryzae conidial germination, appressorium formation, and rice blast by 61, 82 and 84%, respectively. W. circinata, a unique bioagent, controls four rice pathogens from mechanisms of parasitism and antibiosis. The results could contribute to new formulations containing this fungus, enzymes as well as its volatile metabolites.

A produção de arroz é afetada por patógenos importantes como Magnaporthe oryzae, Cochliobolus miyabeanus, Monographella albescens e Sarocladium oryzae, e fungos micorrízicos de orquídeas podem contribuir para o biocontrole dessas doenças. O objetivo deste estudo foi caracterizar os mecanismos de antagonismo de W. circinata contra patógenos do arroz. O ácido indolacético (AIA) e as enzimas líticas de W. circinata foram quantificadas. A eficácia do bioagente e seus metabólitos foi avaliada in vitro. O antagonismo in vivo contra a brusone do arroz também foi investigado. Waitea circinata produziu AIA (2,3 µg ml¹), celulase e polifenol oxidase em teste qualitativo. Glucanase, quitinase e protease também foram produzidas em cultura com paredes celulares e em co-cultura com patógenos para explicar a antibiose. W. circinata atua no antagonismo direto por antibiose e metabólitos voláteis. A suspensão micelial reduziu a germinação de conídios de M. oryzae, a formação de apressórios e a brusone do arroz em 61, 82 e 84%, respectivamente. W. circinata, um bioagente único, controla quatro patógenos do arroz a partir de mecanismos de parasitismo e antibiose. Os resultados podem contribuir para novas formulações contendo este fungo, enzimas, bem como seus metabólitos voláteis.

Upland rice seedling performance promoted by multifunctional microorganisms / Desempenho de plântulas de arroz de terras altas promovido por microrganismos multifuncionais

Multifunctional microorganisms can contribute to the development of plant root systems and positively affect the grain yield of crops. However, studies of the use of these microorganisms to benefit root development in rice plants are scarce. The objective of this study was to determine the effect of rhizobacterial inoculation of the seeds on the root development of upland rice seedlings. The experiment was carried out in the agricultural microbiology laboratory of Embrapa Rice and Beans, and we adopted a completely randomized design with eight replications. The treatments consisted of the inoculation of rice seeds with the rhizobacteria 1. Pseudomonas fluorescens (BRM 32111), 2. Burkholderia pyrrocinia (BRM 32113), 3. Serratia sp. (BRM 32114), 4. Bacillus sp. (1301), 5. Azospirillum brasilense (Ab-V5), 6. Azospirillum sp. (1381), and a 7. control treatment (without microorganisms). Treatment using the microorganism Azospirillum sp. (1381) provided the longest roots, greatest root volume and highest total dry mass of roots, at 86.34, 111.53 and 29.41%, respectively, significantly superior to the control treatment. In addition, treatments Ab-V5 and Bacillus sp. (1301) resulted in a root diameter of 13.81 and 13.06%, respectively, larger than that of the control treatment. The use of these multifunctional microorganisms was efficient for promoting the root development of rice seedlings.(AU)

Microrganismos multifuncionais podem contribuir para o desenvolvimento do sistema radicular de plantas afetando positivamente a produtividade de grãos das culturas. Objetivou-se determinar o efeito da inoculação de rizobactérias em sementes no desenvolvimento radicular de plântulas do arroz de terras altas. O experimento foi conduzido no laboratório de microbiologia agrícola da Embrapa Arroz e Feijão, e adotando delineamento experimental inteiramente casualizado, com oito repetições. Os tratamentos consistiram da inoculação em sementes de arroz com as rizobactérias 1. Pseudomonas fluorescens (BRM 32111), 2. Burkholderia pyrrocinia (BRM 32113), 3. Serratia sp. (BRM 32114), 4. Bacillus sp. (1301), 5. Azospirillum brasilense (Ab-V5), 6. Azospirillum sp. (1381), e 7. tratamento controle (sem microrganismo). O tratamento com a utilização do microrganismo Azospirillum sp. (1381) proporcionou maior comprimento radicular, volume de raízes e massa seca total de raízes, sendo respectivamente, 86,34, 111,53 e 29,41%, superior ao tratamento controle e diferiu significativamente. Além disso, os tratamentos Ab-V5 e Bacillus sp. (1301) proporcionaram maior diâmetro radicular nas plantas de arroz, sendo 13,81 e 13,06 % respectivamente superior ao tratamento controle. O uso destes microrganismos multifuncionais foi eficiente em sua capacidade de proporcionar incrementos no desenvolvimento radicular de plântulas de arroz.(AU)

Trichoderma asperellumand rhizobacteria improving biomass accumulation and gas exchange of lowland rice / Thichoderma asperellum e rizobactérias melhorando o acúmulo de biomassa e trocas gasosas em arroz irrigado

Rice the main source of energy to maintain the metabolism for almost four billion people worldwide. Riceplants treated with multifunctional microorganisms may be a good way for sustainable improvement of crop grain yield. Aimed study the effect of types and ways of microorganisms application in tropical lowland rice production, evaluated by biomass production and gas exchange. The greenhouse trial was in a completely randomized design, in factorial scheme 7 x 3 + 1, with four replication. Treatments were the combination of seven microorganisms: Bacillussp. (BRM32109 e BRM32110); Pseudomonas fluorescens(BRM32111); Pseudomonassp. (BRM32112); Burkholderia pyrrocinia(BRM32113); Serratiasp. (BRM32114) and Trichoderma asperellum pool (UFRA.T06 + UFRA.T09 + UFRA.T12 + UFRA.T52), with three forms of application (1. microbiolized seed; 2. microbiolized seed + soil drenched with microorganism at eight and 15 days after sowing (DAS)and 3. microbiolized seed + microorganism spray plant at eight and 15 DAS). Microbiolized seed was the best form of application, which allowed highest instantaneous carboxylation efficiency and yield of biomassproduction in lowland rice. Rhizobcteria BRM32114, followed by BRM32111, BRM32112 and fungi T. asperellum improved, an average, 17% in instantaneous carboxylation efficiency and 20% in dry shoot biomass production of lowland rice compared to the control plants.

Arroz é a principal fonte de energia para manutenção do metabolismo de quase quarto bilhões de pessoas no mundo todo. Plantas de arroz tratadas com microrganismos multifuncionais pode ser uma boa maneira para melhoria sustentável do rendimento de grãos. Objetivou-se estudar o efeito de tipos e formas de aplicação de microrganismos na produção de arroz irrigado tropical, avaliado pela produção de biomassa e trocas gasosas. Ensaio em casa de vegetação foi realizado em delineamento inteiramente casualizado, no esquema fatorial 7 x 3 + 1, com quatro repetições. Tratamentos consistiram da combinação de sete microrganismos: Bacillussp. (BRM32109 e BRM32110); Pseudomonas fluorescens(BRM32111); Pseudomonassp. (BRM32112); Burkholderia pyrrocinia(BRM32113); Serratiasp. (BRM32114) e Trichoderma asperellumpool (UFRA.T06 + UFRA.T09 + UFRA.T12 + UFRA.T52), com três formas de aplicação (1. semente microbiolizada; 2. semente microbiolizada + solo inundado com os microrganismos aos oito e 15 dias após a semeadura (DAS); e 3. semente microbiolizada + pulverização dos microrganismos nas plantas aos oito e 15 DAS). Microbiolização de sementes foi a melhor forma de aplicação dos microrganismos, o qual promoveu a maior taxa de eficiência instantânea de carboxilação e rendimento da produção de biomassa em arroz irrigado. Rizobactéria BRM32114, seguido por BRM32111, BRM32112 e fungo T. asperellum aumentaram, em média, 17% na eficiência instantânea de carboxilação e, 20% na produção de biomassa seca da parte aérea de arroz irrigado comparado com plantas controle.

Trichoderma asperellumand rhizobacteria improving biomass accumulation and gas exchange of lowland rice / Thichoderma asperellum e rizobactérias melhorando o acúmulo de biomassa e trocas gasosas em arroz irrigado

Rice the main source of energy to maintain the metabolism for almost four billion people worldwide. Riceplants treated with multifunctional microorganisms may be a good way for sustainable improvement of crop grain yield. Aimed study the effect of types and ways of microorganisms application in tropical lowland rice production, evaluated by biomass production and gas exchange. The greenhouse trial was in a completely randomized design, in factorial scheme 7 x 3 + 1, with four replication. Treatments were the combination of seven microorganisms: Bacillussp. (BRM32109 e BRM32110); Pseudomonas fluorescens(BRM32111); Pseudomonassp. (BRM32112); Burkholderia pyrrocinia(BRM32113); Serratiasp. (BRM32114) and Trichoderma asperellum pool (UFRA.T06 + UFRA.T09 + UFRA.T12 + UFRA.T52), with three forms of application (1. microbiolized seed; 2. microbiolized seed + soil drenched with microorganism at eight and 15 days after sowing (DAS)and 3. microbiolized seed + microorganism spray plant at eight and 15 DAS). Microbiolized seed was the best form of application, which allowed highest instantaneous carboxylation efficiency and yield of biomassproduction in lowland rice. Rhizobcteria BRM32114, followed by BRM32111, BRM32112 and fungi T. asperellum improved, an average, 17% in instantaneous carboxylation efficiency and 20% in dry shoot biomass production of lowland rice compared to the control plants.(AU)

Arroz é a principal fonte de energia para manutenção do metabolismo de quase quarto bilhões de pessoas no mundo todo. Plantas de arroz tratadas com microrganismos multifuncionais pode ser uma boa maneira para melhoria sustentável do rendimento de grãos. Objetivou-se estudar o efeito de tipos e formas de aplicação de microrganismos na produção de arroz irrigado tropical, avaliado pela produção de biomassa e trocas gasosas. Ensaio em casa de vegetação foi realizado em delineamento inteiramente casualizado, no esquema fatorial 7 x 3 + 1, com quatro repetições. Tratamentos consistiram da combinação de sete microrganismos: Bacillussp. (BRM32109 e BRM32110); Pseudomonas fluorescens(BRM32111); Pseudomonassp. (BRM32112); Burkholderia pyrrocinia(BRM32113); Serratiasp. (BRM32114) e Trichoderma asperellumpool (UFRA.T06 + UFRA.T09 + UFRA.T12 + UFRA.T52), com três formas de aplicação (1. semente microbiolizada; 2. semente microbiolizada + solo inundado com os microrganismos aos oito e 15 dias após a semeadura (DAS); e 3. semente microbiolizada + pulverização dos microrganismos nas plantas aos oito e 15 DAS). Microbiolização de sementes foi a melhor forma de aplicação dos microrganismos, o qual promoveu a maior taxa de eficiência instantânea de carboxilação e rendimento da produção de biomassa em arroz irrigado. Rizobactéria BRM32114, seguido por BRM32111, BRM32112 e fungo T. asperellum aumentaram, em média, 17% na eficiência instantânea de carboxilação e, 20% na produção de biomassa seca da parte aérea de arroz irrigado comparado com plantas controle.(AU)

Bactérias promotoras do crescimento radicular em plântulas de dois cultivares de arroz irrigado por inundação / Growth promoting bacteria on root lenght of seedlings of two flooded lowland rice cultivars

Para o crescimento e desenvolvimento na natureza, as plantas contam com os benefícios de microrganismos residentes em sua rizosfera. Rizobactérias promotoras de crescimento vegetal (RPCV) são exemplos desses microrganismos que interagem de forma benéfica com espécies vegetais. Portanto, a inoculação de sementes com RPCV pode representar uma alternativa importante e sustentável para melhorar o desenvolvimento inicial e a produção de plantas cultivadas. Objetivou-se com esse estudo determinar o efeito da microbiolização de sementes com RPCV no comprimento radicular de plântulas de arroz irrigado por inundação. Em condições controladas, conduziram-se dois experimentos com cultivares de arroz irrigado (BRS Catiana e BRS A702 CL), em delineamento inteiramente casualizado, com sete tratamentos e 10 repetições. Os tratamentos constituíram-se de seis microrganismos: BRM32109 (Bacillus sp.), BRM32110 (Bacillus sp.), BRM32111 (Pseudomonas fluorescens), BRM32112 (Pseudomonas sp.), BRM32113 (Burkholderia pyrrocinia), BRM32114 (Serratia sp.) e um controle (sem microrganismo). Os maiores comprimentos radiculares foram apresentados pelas sementes tratadas com os isolados BRM32110, BRM32112, BRM32109 e BRM32114. Para ambas cultivares houve significância quando comparado microrganismos e controle. Destaque para as sementes da cultivar BRS Catiana, que quando tratadas com os isolados BRM32110 e BRM32112 apresentaram aumento médio de 25, 7% no comprimento radicular, em comparação com o tratamento controle. Para a cultivar BRS A702CL, todos os microrganismos proporcionaram incrementos com um valor médio de 31% no comprimento radicular das plântulas de arroz. Com base nos resultados pode-se inferir que as RPCV proporcionam incrementos significativos no comprimento radicular de plântulas de cultivares de arroz irrigado por inundação.

For growing and development in nature, plants count with the benefits of microorganisms residing in their rhizosphere. Plant growth promoting rhizobacteria (PGPR) are some of these microorganisms that interact in a beneficial way with plant species. Therefore, seed inoculation with PGPR can be an important and sustainable alternative to improve initial development and crop production. The aim was to determine effect of seeds microbiolization with PGPR on root length of flooded lowland rice seedlings. Under controlled conditions, two experiments were conducted with lowland rice cultivars (BRS Catiana and BRS A702 CL) in completely randomized design, with seven treatments and 10 replications. The treatments consisted of six microorganisms: BRM32109 (Bacillus sp.), BRM32110 (Bacillus sp.), BRM32111 (Pseudomonas fluorescens), BRM32112 (Pseudomonas sp.), BRM32113 (Burkholderia pyrrocinia), BRM32114 (Serratia sp.) and a control (no microorganism). Only the cultivar BRS Catiana showed difference among the treatments. The highest root length was presented by the seeds treated with the isolates BRM32110, BRM32112, BRM32109, and BRM32114. Both of cultivars had significance when compared microorganisms to the control. Highlight for seeds of cultivar BRS Catiana, that when treated with the isolates BRM32110 and BRM32112 presented an average increase of 25. 7% on the root length, compared to control treatment. For the cultivar BRS A702 CL, all the microorganisms provided increments with average value of 31% in the root length of rice seedlings. Based on the results it can be inferred that PGPR provide significant increases in seedling root length of flooded lowland rice cultivars.

Bactérias promotoras do crescimento radicular em plântulas de dois cultivares de arroz irrigado por inundação / Growth promoting bacteria on root lenght of seedlings of two flooded lowland rice cultivars

Para o crescimento e desenvolvimento na natureza, as plantas contam com os benefícios de microrganismos residentes em sua rizosfera. Rizobactérias promotoras de crescimento vegetal (RPCV) são exemplos desses microrganismos que interagem de forma benéfica com espécies vegetais. Portanto, a inoculação de sementes com RPCV pode representar uma alternativa importante e sustentável para melhorar o desenvolvimento inicial e a produção de plantas cultivadas. Objetivou-se com esse estudo determinar o efeito da microbiolização de sementes com RPCV no comprimento radicular de plântulas de arroz irrigado por inundação. Em condições controladas, conduziram-se dois experimentos com cultivares de arroz irrigado (BRS Catiana e BRS A702 CL), em delineamento inteiramente casualizado, com sete tratamentos e 10 repetições. Os tratamentos constituíram-se de seis microrganismos: BRM32109 (Bacillus sp.), BRM32110 (Bacillus sp.), BRM32111 (Pseudomonas fluorescens), BRM32112 (Pseudomonas sp.), BRM32113 (Burkholderia pyrrocinia), BRM32114 (Serratia sp.) e um controle (sem microrganismo). Os maiores comprimentos radiculares foram apresentados pelas sementes tratadas com os isolados BRM32110, BRM32112, BRM32109 e BRM32114. Para ambas cultivares houve significância quando comparado microrganismos e controle. Destaque para as sementes da cultivar BRS Catiana, que quando tratadas com os isolados BRM32110 e BRM32112 apresentaram aumento médio de 25, 7% no comprimento radicular, em comparação com o tratamento controle. Para a cultivar BRS A702CL, todos os microrganismos proporcionaram incrementos com um valor médio de 31% no comprimento radicular das plântulas de arroz. Com base nos resultados pode-se inferir que as RPCV proporcionam incrementos significativos no comprimento radicular de plântulas de cultivares de arroz irrigado por inundação.(AU)

For growing and development in nature, plants count with the benefits of microorganisms residing in their rhizosphere. Plant growth promoting rhizobacteria (PGPR) are some of these microorganisms that interact in a beneficial way with plant species. Therefore, seed inoculation with PGPR can be an important and sustainable alternative to improve initial development and crop production. The aim was to determine effect of seeds microbiolization with PGPR on root length of flooded lowland rice seedlings. Under controlled conditions, two experiments were conducted with lowland rice cultivars (BRS Catiana and BRS A702 CL) in completely randomized design, with seven treatments and 10 replications. The treatments consisted of six microorganisms: BRM32109 (Bacillus sp.), BRM32110 (Bacillus sp.), BRM32111 (Pseudomonas fluorescens), BRM32112 (Pseudomonas sp.), BRM32113 (Burkholderia pyrrocinia), BRM32114 (Serratia sp.) and a control (no microorganism). Only the cultivar BRS Catiana showed difference among the treatments. The highest root length was presented by the seeds treated with the isolates BRM32110, BRM32112, BRM32109, and BRM32114. Both of cultivars had significance when compared microorganisms to the control. Highlight for seeds of cultivar BRS Catiana, that when treated with the isolates BRM32110 and BRM32112 presented an average increase of 25. 7% on the root length, compared to control treatment. For the cultivar BRS A702 CL, all the microorganisms provided increments with average value of 31% in the root length of rice seedlings. Based on the results it can be inferred that PGPR provide significant increases in seedling root length of flooded lowland rice cultivars.(AU)

Cytological aspects of incompatible and compatible interactions between rice, wheat and the blast pathogen Pyricularia oryzae

Blast, caused by the fungus Pyricularia oryzae, is an important disease affecting rice and wheat yield worldwide. This study investigated the cytological aspects of incompatible (non-host resistance) and compatible (host resistance) rice- (R_Po) and wheat- (W_Po) Pyricularia oryzae isolate interactions. Inoculations of rice and wheat with the R_Po and W_Po isolates of P. oryzae, respectively, were expected to be compatible interactions (host resistance), whereas inoculations of rice and wheat with the W_Po and R_Po isolates of P. oryzae, respectively, were considered to be incompatible interactions (non-host resistance). For the compatible interactions (rice-R_Po and wheat-W_Po), fungal hyphae penetrated and colonized the epidermal cells and also invaded many neighboring cells. By contrast, in the case of the incompatible interactions (rice-W_Po and wheat-R_Po), fungal hyphae were not able to penetrate nor colonize the epidermal cells, but when penetration did occur, the hyphae were restricted to the first-invaded epidermal cell. The frequency of appressorial sites exhibiting infection hyphae within the epidermal cell underlying an appressorium was greater in the case of the compatible interactions. By contrast, unsuccessful penetrations with cytoplasmic granulation occurred with high frequency in the incompatible wheat-R_Po and rice-W_Po interactions and the number of necrotic epidermal cells underlying the appressorium was low for the rice-W_Po interaction as well as for the wheat- R_Po interaction, where no symptoms of necrosis were exhibited. However, the opposite was observed for the compatible interactions. The present study presents cytological features associated with incompatible and compatible rice- and wheat-P. oryzae interactions that may be useful to studies involving variability, coevolution, diagnosis, and regulation of quarantine or even in a rice or wheat breeding program whose aim is to transfer genes involved in non-host resistance to host resistance due to similarities in downstream mechanisms.

Cytological aspects of incompatible and compatible interactions between rice, wheat and the blast pathogen Pyricularia oryzae

Blast, caused by the fungus Pyricularia oryzae, is an important disease affecting rice and wheat yield worldwide. This study investigated the cytological aspects of incompatible (non-host resistance) and compatible (host resistance) rice- (R_Po) and wheat- (W_Po) Pyricularia oryzae isolate interactions. Inoculations of rice and wheat with the R_Po and W_Po isolates of P. oryzae, respectively, were expected to be compatible interactions (host resistance), whereas inoculations of rice and wheat with the W_Po and R_Po isolates of P. oryzae, respectively, were considered to be incompatible interactions (non-host resistance). For the compatible interactions (rice-R_Po and wheat-W_Po), fungal hyphae penetrated and colonized the epidermal cells and also invaded many neighboring cells. By contrast, in the case of the incompatible interactions (rice-W_Po and wheat-R_Po), fungal hyphae were not able to penetrate nor colonize the epidermal cells, but when penetration did occur, the hyphae were restricted to the first-invaded epidermal cell. The frequency of appressorial sites exhibiting infection hyphae within the epidermal cell underlying an appressorium was greater in the case of the compatible interactions. By contrast, unsuccessful penetrations with cytoplasmic granulation occurred with high frequency in the incompatible wheat-R_Po and rice-W_Po interactions and the number of necrotic epidermal cells underlying the appressorium was low for the rice-W_Po interaction as well as for the wheat- R_Po interaction, where no symptoms of necrosis were exhibited. However, the opposite was observed for the compatible interactions. The present study presents cytological features associated with incompatible and compatible rice- and wheat-P. oryzae interactions that may be useful to studies involving variability, coevolution, diagnosis, and regulation of quarantine or even in a rice or wheat breeding program whose aim is to transfer genes involved in non-host resistance to host resistance due to similarities in downstream mechanisms.(AU)

An approach on phytoalexins: function, characterization and biosynthesis in plants of the family Poaceae / Uma abordagem sobre fitoalexinas: função, caracterização e biossíntese em plantas da família Poaceae

Phytoalexins are compounds that have been studied a few years ago, which present mainly antimicrobial activity. The plants of the family Poaceae are the most geographically widespread and stand out for their economic importance, once they are cereals used as staple food. This family stands out for having a variety of phytoalexins, which can be synthesized via the shikimic acid (the phenylpropanoids), or mevalonic acid, being considered terpenoid phytoalexins. The characterization of these compounds with antimicrobial activity is carried out using chromatographic techniques, and the high-performance liquid chromatography (HPLC) coupled with mass spectrometry are the most efficient methods in this process. This research aimed to present an approach of the function, characterization and biosynthesis of phytoalexins in plants of the family Poaceae.(AU)

As fitoalexinas são compostos que vêm sendo estudados há alguns anos, apresentando principalmente atividade antimicrobiana. As plantas da família Poaceae são as geograficamente mais difundidas e se destacam por sua importância econômica, uma vez que são os cereais que compõe a base da alimentação, em todos os continentes. Essa família se destaca por apresentar uma variedade de fitoalexinas, sendo que as mais importantes são sintetizadas a partir da via do ácido chiquímico. A caracterização desses compostos com atividade antimicrobiana é realizada por meio de técnicas cromatográficas, sendo que a cromatografia líquida de alta eficiência (HPLC) acoplada com espectrometria de massas é a técnica mais eficiente nesse processo. O trabalho apresenta como objetivo uma abordagem da função, caracterização, biossíntese e aplicações das fitoalexinas em plantas da família Poaceae.(AU)