ABSTRACT Cowpea is one of the major food crops in Northeast Brazil, where it is commonly cultivated in the semi-arid regions with limited water availability. It is important to study the elicitors associated with cowpea to mitigate any deleterious effects of abiotic stress on the initial establishment of this crop. In this study, we aimed to evaluate the morphophysiological changes in cowpea cultivars under osmotic stress with seeds soaked in salicylic acid. The germination test was conducted in B.O.D germination chambers. The seeds of three cowpea cultivars: BRS Tumucumaque, BRS Aracê, and BRS Guariba, were germinated at five osmotic potentials (0.0; -0.2; -0.4; -0.6, and -0.8 MPa) after three pre-treatments: pre-soaking in deionized water, pre-soaking in salicylic acid, and without pre-soaking. The following parameters were evaluated: germination, germination speed index, seedling height, total phytomass, contents of chlorophyll ‘a’ and ‘b’, carotenoid content, electrolyte leakage, water content, and proline content. Our results indicate that salicylic acid promotes reduction in the harmful effects of abiotic stress, which is reflected in the increase in germination percentage, seedling height, and chlorophyll and carotenoid content as well as in the adjustment of electrolyte leakage and increase in proline content under induced water stress conditions. The cultivar BRS Guariba proved to be more tolerant to water deficit during germination and initial growth stages, when the seeds were treated with salicylic acid (1 mM). | RESUMO O feijão-caupi é uma das principais culturas alimentares no Nordeste do Brasil, onde é geralmente cultivada nas regiões semiáridas com pouca disponibilidade de água. É importante estudar os elicitores associados ao caupi para mitigar os efeitos deletérios do estresse abiótico no estabelecimento inicial desta cultura. Neste estudo, buscaram-se avaliar as alterações morfofisiológicas em cultivares de caupi sob estresse osmótico com sementes embebidas em ácido salicílico. O teste de germinação foi realizado em câmaras de germinação B.O.D. As sementes de três cultivares de caupi: BRS Tumucumaque, BRS Aracê e BRS Guariba foram germinadas em cinco potenciais osmóticos (0,0; -0,2; -0,4; -0,6 e -0,8 MPa) após três pré-tratamentos: pré-imersão em Água desionizada, pré-imersão em ácido salicílico e sem pré-imersão. Foram avaliados os seguintes parâmetros: germinação, índice de velocidade de germinação, altura da plântula, fitometria total, conteúdo de clorofila 'a' e 'b', conteúdo de carotenóides, vazamento eletrolítico, teor de água e conteúdo de prolina. Os resultados indicam que o ácido salicílico promove a redução dos efeitos nocivos do estresse abiótico, o que se reflete no aumento da porcentagem de germinação, altura da plântula e teor de clorofila e carotenóides, bem como no ajuste do vazamento eletrolítico e aumento do teor de prolina sob condições de estresse hídrico. A cultivar BRS Guariba mostrou-se mais tolerante ao déficit de água durante a germinação e estágios de crescimento inicial, quando as sementes foram tratadas com ácido salicílico (1 mM).

Cowpea is one of the major food crops in Northeast Brazil, where it is commonly cultivated in the semi-arid regions with limited water availability. It is important to study the elicitors associated with cowpea to mitigate any deleterious effects of abiotic stress on the initial establishment of this crop. In this study, we aimed to evaluate the morphophysiological changes in cowpea cultivars under osmotic stress with seeds soaked in salicylic acid. The germination test was conducted in B.O.D germination chambers. The seeds of three cowpea cultivars: BRS Tumucumaque, BRS Aracê, and BRS Guariba, were germinated at five osmotic potentials (0.0; -0.2; -0.4; -0.6, and -0.8 MPa) after three pre-treatments: pre-soaking in deionized water, pre-soaking in salicylic acid, and without pre-soaking. The following parameters were evaluated: germination, germination speed index, seedling height, total phytomass, contents of chlorophyll ‘a’ and ‘b’, carotenoid content, electrolyte leakage, water content, and proline content. Our results indicate that salicylic acid promotes reduction in the harmful effects of abiotic stress, which is reflected in the increase in germination percentage, seedling height, and chlorophyll and carotenoid content as well as in the adjustment of electrolyte leakage and increase in proline content under induced water stress conditions. The cultivar BRS Guariba proved to be more tolerant to water deficit during germination and initial growth stages, when the seeds were treated with salicylic acid (1 mM).

RESUMO: A utilização de plantas medicinais na fitoterapia do Sistema Único de Saúde no Brasil tem intensificado o cultivo e a necessidade de desenvolvimento de técnicas agronômicas eficientes para promover maior produtividade destas espécies. O objetivo do presente trabalho foi avaliar a produção da camomila a campo em função de lâminas de irrigação e doses de adubo orgânico. O ensaio foi conduzido em área experimental do campus II, da Universidade do Oeste Paulista, na cidade de Presidente Prudente - SP, Brasil. O delineamento experimental foi em esquema fatorial triplo, sendo composto por lâminas de irrigação (150, 100, 75, 50, 25 e 0% da evapotranspiração de referência - ETo), tipos de adubo orgânico (esterco de aves e esterco bovino curtido) e doses do adubo (0, 3 e 5 kg m-2), em quatro repetições. Foram avaliadas a produção de capítulos florais por planta, a massas seca dos capítulos florais e a produtividade da água. Para a região de Presidente Prudente, a irrigação suplementar combinada à adubação orgânica, proporcionaram maior produção de capítulos florais. A combinação de esterco de aves na dose de 5 kg m-2 à lâmina de 150% ETo resultou em maiores valores médios de massa fresca e seca de capítulos florais e produtividade da água. | ABSTRACT: The use of medicinal plants in the herbal medicine of Brazilian Health System has intensified production and the need for developing efficient agricultural techniques that promote greater productivity of these species. The objective of this work was to evaluate the chamomile production at field conditions as a function of irrigation depths and organic fertilizer rates. The experiment was conducted in the Universidade do Oeste Paulista (Campus II experimental area), in Presidente Prudente, São Paulo State, Brazil. A triple factorial experimental design was used, consisting of irrigation rates (150, 100, 75, 50, 25 and 0% of the reference evapotranspiration - ETo), organic manure types (poultry and cattle manure) and manure rates (0, 3 and 5 kg m-2), with four replications. The capitula production per plant, capitula dry weight and yield per water input (water use efficiency) were evaluated. The supplementary irrigation combined with organic manure fertilization provided the highest capitula yield for chamomile crop in the Presidente Prudente region. The combination of poultry manure at rate of 5 kg m-2 with water depth equal to 150% of the ETo resulted in higher average values of capitula fresh and dry weight and water use efficiency.

The use of medicinal plants in the herbal medicine of Brazilian Health System has intensified production and the need for developing efficient agricultural techniques that promote greater productivity of these species. The objective of this work was to evaluate the chamomile production at field conditions as a function of irrigation depths and organic fertilizer rates. The experiment was conducted in the Universidade do Oeste Paulista (Campus II experimental area), in Presidente Prudente, São Paulo State, Brazil. A triple factorial experimental design was used, consisting of irrigation rates (150, 100, 75, 50, 25 and 0% of the reference evapotranspiration - ETo), organic manure types (poultry and cattle manure) and manure rates (0, 3 and 5 kg m-2), with four replications. The capitula production per plant, capitula dry weight and yield per water input (water use efficiency) were evaluated. The supplementary irrigation combined with organic manure fertilization provided the highest capitula yield for chamomile crop in the Presidente Prudente region. The combination of poultry manure at rate of 5 kg m-2 with water depth equal to 150% of the ETo resulted in higher average values of capitula fresh and dry weight and water use efficiency.