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Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Brazil stands out as one of the world's main producers of tilapia, but the significant increase in the production of this species, essential for the global fishing industry, brings considerable challenges and environmental impacts. The significant generation of waste from tilapia farming emerges as a significant environmental concern associated with the expansion of aquaculture. Given this scenario, this study aimed to evaluate the plant growth and production of organic solutes in sunflower plants subjected to drought stress conditions and cultivated with fertilizer from tilapia scales (EDT). The experiment was conducted in a controlled environment, using pots with two plants, organized in a 2x6 factorial arrangement. The factors included two water regimes (daily irrigation and suspension of irrigation 20 days after sowing) and six different substrates:1) 100% (by volume) fine-grained sand; 2) Sand + Fertilizer at 80 kg N ha-1; 3) Sand + EDT at 80 kg N ha-1; 4) Sand + EDT at 120 kg N ha-1; 5) Sand + EDT at 180 kg N ha-1; 6) Sand + EDT at 240 kg N ha-1. The use of tilapia scale (EDT) as an organic biofertilizer caused an increase in organic solute levels, especially under water stress conditions. This circumstance may have contributed, at least partially, to attenuating the deleterious effects of water stress on plant growth. The ideal EDT concentration was identified as 120 kg of nitrogen per hectare. [ABSTRACT FROM AUTHOR]

Cowpea is a food crop representing an important source of proteins and income, mainly for people living in the north and northeast of Brazil. This study aimed to evaluate the growth performance of two cowpea cultivars under four different ionic concentrations of the growth solution. Thus, a pot experiment was performed using the sand culture technique and set up in a completely randomized design with a 2 x 4 factorial scheme, using four replications and one plant per plot. After the period of growth, the parameters such as length of the shoot, stem diameter, number of leaves, number of secondary branches, number of pods, fresh weight of the stem, stem dry mass, leaf dry mass, shoot dry mass, and root/shoot ratio were obtained. The results pointed out that there was a significant interaction effect on parameters like stem diameter, leaf dry mass, shoot dry mass, and number of leaves. Both cultivars were strongly responsive to changes in ionic concentration, indicating a greater biomass production at ionic concentrations of 90% and 120%. A greater growth performance for BRS Rouxinol than BRS Itaim was observed, while the second cultivar indicated a high tolerance as exposed to the highest ionic concentrations. [ABSTRACT FROM AUTHOR]

A propagação da palmeira jerivá (Syagrus romanzoffiana) ocorre por meio de sementes, cuja germinação se dá de forma desuniforme e lenta. Assim, as sementes encontram-se sujeitas a múltiplos estresses, como o hídrico e o salino, que limitam a embebição e suas chances de germinação. Objetivou-se avaliar a germinação de sementes da palmeira jerivá submetidas aos estresses hídrico e salino. O delineamento utilizado foi o inteiramente casualizado, com quatro repetições, em esquema fatorial (2 × 5), sendo dois agentes osmocondicionantes (NaCl e PEG 6000) e cinco potenciais osmóticos (0,0 - controle, -0,3, -0,6, -0,9 e -1,2 MPa). Ao final do experimento, calculou-se: porcentagem de germinação, índice de velocidade de germinação e tempo médio de germinação. Com relação aos potenciais osmóticos, para porcentagem de germinação, houve efeito significativo de maneira isolada somente para NaCl, com diminuição na porcentagem de acordo com a redução do potencial osmótico da solução. A partir do potencial -0,6 MPa, houve redução significativa na germinação das sementes. O índice de velocidade e o tempo médio de germinação das sementes foram afetados negativamente pelos potenciais osmóticos das soluções, independente do agente osmocondicionante. No estresse hídrico simulado pelo PEG 6000, as sementes começaram a germinar mais tarde e por um período mais prolongado, quando comparado àquelas submetidas ao estresse de NaCl. Concluiu-se que as sementes da palmeira jerivá apresentam tolerância aos estresses hídrico e salino, pois conseguiram germinar até mesmo no potencial osmótico mais negativo (-1,2 MPa).

Plant yield is directly affected by the increase in air temperature and the water availability in the soil. Therefore, the objective with this study was to evaluate the physiological and productive performance of sorghum cultivars as a function of soil water availability and temperature at the cultivation time. The research was carried out at Embrapa Semi-Arid, municipality of Petrolina, Pernambuco state, Northeast region, Brazil, with planting in June 2021 and January 2022. The experiment was conducted in a randomized block design with a 2 × 6 × 4 factorial arrangement, with two growing seasons (season 1: planting in June; season 2: planting in January), six sorghum cultivars (AGRI002E, BRS 716, BRS 506, SF 15, IAC Santa Elisa and BRS Ponta Negra) and four water availability levels (25, 50, 75, and 100%), with four replications. The following variables were evaluated: total dry mass, water use efficiency, photosynthesis, stomatal conductance, transpiration and leaf temperature. The SF 15 and BRS Ponta Negra cultivars produced the highest amount of total dry mass when planted in June, with maximum temperatures ranging from 26 to 34 °C and 100% water availability. The AGRI002E cultivar showed higher dry mass production, photosynthesis, stomatal conductance and leaf transpiration rates among the other cultivars in season 2, with 100% of soil water retention capacity, demonstrating adaptation to the increase in temperature. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Agricultural Research in the Tropics / Pesquisa Agropecuária Tropical is the property of Pesquisa Agropecuaria Tropical and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A palmeira triângulo (Dypsis decaryi), nativa de Madagascar e ameaçada de extinção em seu habitat, apresenta diversas características de interesse ornamental, tornando-a uma espécie importante para o mercado internacional. O principal método de propagação desta planta é por semente, que é influenciado por vários fatores como época de semeadura e salinidade. A variação de fatores ambientais em diferentes épocas de semeadura pode influenciar o processo de germinação enquanto que o estresse salino pode causar diminuição na germinação e até morte de sementes, afetando a produção de mudas. Desta forma, o objetivo deste trabalho foi avaliar o comportamento germinativo de sementes de Dypsis decaryi em diferentes concentrações salinas de cloreto de sódio (NaCl) e cloreto de potássio (KCl) em duas épocas. O delineamento experimental utilizado foi o inteiramente casualizado; o experimento foi realizado em esquema fatorial 2 x 2 x 5, sendo duas épocas de condução do experimento (verão e inverno), dois tipos de sais (NaCl e KCl) e quatro concentrações salinas (25, 50, 75 e 100 mM) e ausência de sais - controle; foram quatro repetições e 25 sementes por parcela. Foram avaliadas porcentagem de germinação, índice de velocidade de germinação e tempo médio de germinação. A espécie se mostrou tolerante à salinidade simulada por KCl e NaCl, durante o processo de germinação de sementes, o qual foi influenciado pela época de semeadura, concentrações salinas e interação entre épocas e concentrações. Não houve efeito significativo de forma isolada entre os tipos de sais, para interação de épocas e sais e, entre os três fatores avaliados.

A goiabeira é uma cultura importante no cenário socioeconômico da região semiárida brasileira, sendo uma fonte de geração de emprego e renda. Contudo, nesta região é comum a ocorrência de fontes hídricas com altos teores de sais dissolvidos e assim são necessárias estratégias que visem minimizar os efeitos deletérios do estresse salino nas plantas. Neste contexto, objetivou-se com este trabalho avaliar os efeitos da aplicação foliar com peróxido de hidrogênio nas trocas gasosas, eficiência fotoquímica, crescimento e qualidade de mudas de goiabeira sob estresse salino. O experimento foi conduzido sob condições de casa de vegetação em Pombal, Paraíba, utilizando-se o delineamento de blocos casualizados, com tratamentos arranjados em esquema fatorial 5 × 4 , referentes a cinco níveis de condutividade elétrica da água - CEa (0,3; 1,3; 2,3; 3,3 e 4,3 dS m-1) e quatro concentrações de peróxido de hidrogênio – H2O2 (0, 25, 50 e 75 μM) com quatro repetições e duas plantas por parcela. A irrigação com água de condutividade elétrica a partir de 0,3 dS m-1 inibiu as trocas gasosas, eficiência fotoquímica e crescimento de mudas de goiabeira, aos 91 dias após a emergência. A aplicação foliar de peróxido de hidrogênio em concentrações de até 75 μM não amenizou os efeitos do estresse salino em plantas de goiabeira na fase de formação de mudas. A goiabeira cv. Paluma é classificada como sensível a salinidade da água na fase de formação de mudas, sendo o nível limiar de 0,3 dS m-1 e diminuição por aumento unitário de 11,48%.

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to clarify the kind of behavior before damage caused by various agents in their cotyledons. The research was conducted on the premises of the experimental area CCA, UFPI, in the period June- July 2019, with growing Italian Caserta. The experimental design was randomized blocks (DBC) with 4 repetitions and 11 treatments, treatments consisted to simulate different degrees of mechanical damage at different times after the emergence of the zucchini seedlings. Analysis of variance showed a significant difference only on the parameter dry weight of the stem. According to the results obtained from the analysis of dry matter, treatment affected only the stem, not influencing the leaves and roots, since the losses incurred in the removal of the cotyledons, regardless of the number or from the time that it was not affected height, root depth or number of leaves. Regarding the stem, perceive a trend of scathing effects with the removal of two cotyledons, especially in the early plant growth, at which time they are most required. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effects of water and salt stress on initial growth of Australian red cedar (Toona ciliata var. australis) seedlings. Saline stress was evaluated in two completely randomized design (CRD) experiments, considering five osmotic potentials (0.0; -0.3; -0.6; -0.9 and -1.2 MPa). For water stress, five ranges of water potential were evaluated, using CRD (0 to -7; -7.1 to -14.0; -14.1 to -21.0; -21.1 to -28.0 and -28.1 to -35.0 kPa). At the end of both experiments the plant height, stem diameter, aerial part dry mass, roots dry mass, total dry mass and seedling survival were evaluated. Saline solutions application reduced all seedlings development variables. Up to the level of -21 kPa of water stress, there was an increase in height and the plant height and the stem diameter ratio. The other variables have been reduced since the first tested level. The tolerance of seedlings to the stresses evaluated allows for the adjustment of management conditions in the nursery before occuring losses and may also indicate a tolerance to these adverse conditions in the field. [ABSTRACT FROM AUTHOR]

Tomato is a crop sensitive to water deficit and the responses of seeds to germination under these conditions involve biochemical, physiological, and molecular processes. The aim of this study was to evaluate the physical, physiological, and biochemical changes in tomato seeds osmoprimed with selenium (Se) and subjected to water deficit during germination. Tomato seeds of the LA 4050 and LA 3475 accessions were osmoprimed with PEG 6000 solution (-1.0 MPa) plus Na2SeO4 (12.5 µM) or only with PEG 6000 solution for 24 h or unprimed. The seeds from the different treatments were subjected to water deficit (-0.3 MPa) or to control (0 MPa). Image analyses were performed (X-ray), physiological variables were obtained by the germination test and activities of SOD, CAT and POX enzymes were determined. Osmopriming, especially with PEG, provided the seeds of both accessions with higher densities and gray mean when compared to unprimed ones. Seeds under water deficit showed lower physiological performance and lower enzymatic activity. Se did not induce seed resistance to water deficit. Osmopriming with PEG 6000 at -1.0 MPa is an efficient technique for improving the physiological quality of seeds of tomato accessions susceptible and tolerant to water deficit. Moreover, the antioxidant enzyme CAT proved to be an indicator of oxidative stress tolerance in tomato seedlings under water deficit. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Agricultural Research in the Tropics / Pesquisa Agropecuária Tropical is the property of Pesquisa Agropecuaria Tropical and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

O feijão-caupi [Vigna unguiculata (L.) Walp] é amplamente cultivado no Nordeste brasileiro e destaca-se pela sua importância econômica e social. Parte da área de cultivo apresenta algum grau de estresse salino, o que afeta o desempenho da cultura. Os efeitos da salinidade podem ser mitigados com o desenvolvimento de cultivares tolerantes. Objetivou-se com este trabalho avaliar o comportamento de cultivares de feijão-caupi em diferentes níveis de estresse salino, nas fases de germinação e emergência da cultura. Dois ensaios avaliando as fases de germinação e emergência foram conduzidos, sob condições controladas, em esquema fatorial com 11 cultivares em soluções de NaCl com concentração variando de 0 a 120 mM. Houve significativa diferença na resposta das cultivares em função do nível de salinidade aplicado. As cultivares BRS Itaim, BRS Novaera, BRS Pajeu, BRS Tumucumaque, Sempre Verde e Pingo-de-ouro demonstram melhor desempenho nas fases de germinação ou emergência em condições de estresse salino, sendo estas mais promissoras para o estabelecimento inicial da cultura, na presença de salinidade.

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Soybean genotypes have different levels of tolerance to the phytotoxic effects of aluminum (Al3+) and analysis of this characteristic may potentialize the use of acid soils. Current research investigated the effects of aluminum in the germination and initial growth of 25 soybean cultivars and the identification of more tolerant cultivars susceptible to toxicity by Al3+. Assay was conducted at the seed laboratory of the Universidade Estadual de Mato Grosso do Sul in Cassilândia, Brazil. Toxicity by Al3+ was imposed by exposition of seeds to a diluted solution with 15 µmol L-1 of Al3+, plus 1250 µmol L-1 calcium. The pH of solution with Al3+ was adjusted to 4.3 by HCl 0.5 mol L-1. Randomized experimental design comprised four replications with 50 seeds from 25 soybean cultivars and two growth conditions of seedlings (control or stress by Al3+), with a total of 50 treatments. Treatments were evaluated by tolerance indexes to stress (ITE) for seed germination, length and dry matter of seedlings. Toxicity by Al3+ reduced germination and initial growth rate in all the 25 soybean cultivars. Cultivars TMG 7061 IPRO, TMG 7063 IPRO, TMG 7067, HO Paranaíba IPRO and NS 7505 IPRO were indicated since they were bred in acid soils and had the greater tolerance to aluminum toxicity. Cultivars RK 815 IPRO, RK 8317 IPRO and ST 777 IPRO were classified as susceptible to aluminum toxicity and should not be recommended for breeding in acid soils. [ABSTRACT FROM AUTHOR]

Rice production (Oryza sativa L.) is among the most economically important activities in the world. However, soil and salinity coming from irrigation water reduce rice yield. Therefore, the identification and/or development of salt-tolerant rice genotypes is a strategy to minimize this problem. The development of new genotypes depends on the presence of genetic diversity, and understanding the heritability of a desired trait can help in the selection process. Thus, this study aimed to identify superior genotypes, analyze the genetic diversity and estimate the heritability for salinity tolerance at the seedling stage in rice genotypes used in Brazil. For this, seedlings of 69 genotypes were kept in hydroponic solution with 40 mM NaCl (4 dSm-1) for seven days. Shoot length, root length, shoot dry weight, and root dry weight) were evaluated and the results were converted into relative performance. Tolerant and moderately salt-tolerant genotypes were identified at the seedling stage, which can be used in breeding programs and can be cultivated in high salinity areas. Principal component analysis showed the presence of genetic diversity for salinity response. Finally, it was shown that most of the observed variation is of genetic origin, which can make the breeding process less difficult. [ABSTRACT FROM AUTHOR]

Studies have been developed to improve cultivation conditions through the introduction of beneficial compounds, among which are vitamins. The present work aimed to investigate the effects of the application of vitamins in the onion crop. For that, five treatments were used, composed of different vitamins (ascorbic acid, thiamine, niacin and pyridoxine), in a concentration of 100 mg L-1 and a control treatment, with water application, via foliar spray. The characteristics of chlorophyll relative index, number of plant leaves, plant height, fresh leaf mass, leaf dry mass, bulb diameter, bulb mass and bulb yield were evaluated. It was found that the application of ascorbic acid and pyridoxine increased the relative levels of chlorophyll concerning the control treatment and those composed by the application of niacin and thiamine. In addition, for liquid photosynthesis, a superior result was shown when niacin and thiamine were applied, concerning the other treatments. It was concluded that the exogenous application of vitamins alters the physiological and developmental behavior of onion plants, but does not positively affect bulb yield. The increases in photosynthetic activity were not reversed in bulb development, but in the elongation of plant leaves. Finally, the use of the vitamins studied for onion cultivation is not recommended, under conditions similar to those of the present study. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ambiente e Água is the property of Revista Ambiente e Agua and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Drought stress consists of a significant productivity constraint in tomatoes. Two contrasting crosses were performed to estimate physiological and morphological traits in response to drought stress during the vegetative stage, aiming to identify superior genotypes for drought tolerance. Two genotypes (GBT_2037 - sensitive drought-sensitive and GBT_2016 - intermediate drought-tolerant) were used as female parentals, and a commercial hybrid (drought tolerant) was used as a pollen source in both crosses: C1 (GBT_2037 x Commercial hybrid) and C2 (GBT_2016 x Commercial hybrid). The populations of parentals (P), the first generation of descendants (F1), backcrosses (BC), and the second generation of self-pollination (F2) were exposed to drought stress for 20 days when they were analyzed: physiological traits (relative water content of leaves, proline, and relative chlorophyll content) and morphological (plant height, stem diameter, number of leaves, fresh and dry matter of roots and shoot and classification by wilt scale). The means of chlorophyll, root/shoot ratio, and water content in leaves for the F2 generation of C2 were higher than C1, indicating that C2 resulted in plants with greater capacity to maintain turgor under conditions of water stress and presented minor damage to the photosynthetic structures, consequently showing greater tolerance to drought stress. [ABSTRACT FROM AUTHOR]

Drought stress consists of a major productivity constraint in tomato. Two contrastant crosses were performed to estimate physiological and morphological traits involved in the response to drought stress during vegetative stage, aiming to identify superior genotypes for drought tolerance. Two varieties (GBT_2037 – drought sensitive and GBT_2016 – intermediate drought tolerant) were used as female parentals and a commercial hybrid (drought tolerant) was used as a pollen source in both crosses: C1 (GBT_2037 × Commercial hybrid) and C2 (GBT_2016 × Commercial hybrid). The populations of parentals (P), first generation of descendants (F1) and second generation of self-polination (F2) were exposed to drought stress during 20 days, when they were analysed: physiological traits (relative water content of leaves, proline and relative chlorophyll content) and morphological (plant height, stem diameter, number of leaves, fresh and dry matter of roots and shoot and a classification by wilt scale). The means of chlorophyll, root/shoot ratio and water content in leaves for the F2 generation of C2 were higher than C1, indicating that C2 resulted in plants with greater capacity to maintain turgor under conditions of water stress and presented less damage on the photosynthetic structures, consequently showing greater tolerance to drought stress.

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Este trabalho objetivou avaliar o estabelecimento de Anadenanthera colubrina (Vell.) Brenan var. cebil [Griseb.] Altschul sob inoculação micorrízica e fertilização no Pantanal da Nhecolândia, MS. O experimento foi implantado em março de 2015 em ambiente de cordilheira parcialmente desmatada, em blocos ao acaso distribuídos no micro relevo, e parcelas subdivididas. Os principais tratamentos foram constituídos por mudas submetidas ou não (controle) à inoculação mista com Rhizophagus clarus e Gigaspora margarita, e aos tratamentos secundários de adubação com doses de sulfato de amônio e cloreto de potássio. Entre 2015 e 2017 foram avaliados a abertura do dossel das árvores remanescentes, o percentual de sobrevivência e o crescimento de A. colubrina. Melhores condições de sobrevivência foram verificadas na porção da cordilheira mais próxima à baía, sob sombreamento moderado e com a aplicação, no plantio, de 15 g de sulfato de amônio e de 5 g de cloreto de potássio por muda. A inoculação micorrízica promoveu incremento de 16% em diâmetro do colo aos 23 meses de idade, não aumentando a sobrevivência da espécie. Estudos complementares são necessários para subsidiar estratégias de manejo de A. colubrina, em condições de plantio no Pantanal da Nhecolândia.

Urochloa brizantha is the main forage grass to raise cattle in Brazil, but salt stress can reduce yield. Physiological and molecular mechanisms of adaptation to salt stress remain poorly understood in this species. The objective of this work was to evaluate the responses of three cultivars of U. brizantha to in vitro salt stress. Seeds of three cultivars (Piatã, Marandu, and Xaraés) germinated in filter paper and then transferred to growth on culture media in vitro containing 0, 50, 100, and 200 mg L-1 of sodium chloride (NaCl). Biometric parameters and proline content were determined after 28 days. The data were subjected to analysis of variance and the separation of means was performed by the LSD test (p

Urochloa brizantha is the main forage grass to raise cattle in Brazil, but salt stress can reduce yield. Physiological and molecular mechanisms of adaptation to salt stress remain poorly understood in this species. The objective of this study was to evaluate the responses of three cultivars of U. brizantha to in vitro salt stress. Seeds of three cultivars (Piatã, Marandu, and Xaraés) germinated in filter paper and then transferred to growth on culture media in vitro containing 0, 50, 100, and 200 mg L-1 of sodium chloride (NaCl). Biometric parameters and proline content were determined after 28 days. The data were subjected to analysis of variance and the separation of means was performed by the LSD test (p<0.05). Semiquantitative expression of the Δ1-pyrroline-5-carboxylate synthase (P5CS1) gene was performed. In all cultivars, increase of NaCl concentration in the media affected roots and shoots growth. Xaraes cultivar presented the greater biomass reduction while Marandu cultivar was the least affected. Salt stress increased by approximated 0.6 folds transcription of the P5CS1 gene in all cultivars. However, Marandu cultivar presented a higher proline content and least biomass reduction suggesting a better response to in vitro to salt stress. [ABSTRACT FROM AUTHOR]

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disponibilidade de água é um dos principais fatores responsáveis pela produtividade do trigo, bem como da qualidade das sementes produzidas. O silício (Si) possui importante papel na atenuação dos efeitos de diversos estresses bióticos e abióticos. Desta forma, a aplicação de Si pode ser uma ferramenta para mitigar os efeitos de diferentes lâminas de irrigação na produção e qualidade de sementes de trigo. O objetivo do trabalho foi avaliar a produtividade e a qualidade fisiológica de sementes de trigo produzidas a partir de plantas fertilizadas com Si foliar e cultivadas sob diferentes lâminas de irrigação. O delineamento experimental foi blocos casualizados, em esquema de parcelas subdividas, com quatro repetições. As parcelas foram constituídas por três lâminas de irrigação (0, 50 e 100% da irrigação total necessária [ITN]). Nas subparcelas foram alocados os tratamentos de silício (sem aplicação [0 mM] e 5 mM de SiO2, aplicado na fase de perfilhamento). Foram avaliados: balanço hídrico do sistema; umidade do solo; produtividade; massa de mil sementes; germinação; condutividade elétrica; envelhecimento acelerado; comprimento e emergência de plântulas. O balanço hídrico do sistema foi negativo para a lâmina de 0% da ITN após a antese e houve menor umidade do solo nesta lâmina. Não houve efeito das lâminas de irrigação e da aplicação de Si na produtividade das plantas. As menores lâminas de irrigação impostas reduziram a massa de mil sementes e aumentaram a condutividade elétrica das sementes produzidas. Sementes produzidas em plantas fertilizadas com Si não diferiram quanto a germinação, porém originam plântulas mais vigorosas com maior crescimento e uniformidade.

A técnica de condicionamento osmótico reduz o período entre a semeadura e a emergência de mudas no campo, além de favorecer o desempenho das sementes em condições de estresse. O objetivo do estudo foi avaliar o efeito do condicionamento osmótico no desempenho fisiológico e na atividade enzimática antioxidativa de sementes de girassol com diferentes níveis de vigor e expostas ao estresse térmico. Foram utilizados três lotes de sementes de girassol, cultivar Hélio 250. Inicialmente, as sementes foram avaliadas pelos testes de germinação e vigor para caracterizar os lotes. Em seguida, foram condicionadas em solução de polietilenoglicol 6000 a -2,0 MPa, a 15 °C por 8 h. Posteriormente, as sementes condicionadas e não condicionadas foram testadas quanto à qualidade fisiológica (germinação, contagem de primeira germinação, porcentagem e índice de velocidade de emergência das plântulas e matéria seca das plântulas) e determinação da atividade das enzimas superóxido dismutase (SOD), catalase (CAT ), ascorbato peroxidase (APX) e peroxidase (POX) sob três temperaturas: 15 °C (sub ótima), 25 °C (ótima) e 35 °C (supra ótima). Através de testes fisiológicos, os lotes 1, 2 e 3 foram classificados em três níveis diferentes de vigor, sendo alto, médio e baixo, respectivamente. O condicionamento osmótico favoreceu o desempenho das sementes de girassol na germinação e vigor em todas as temperaturas analisadas. Este efeito foi mais pronunciado em lotes de qualidade fisiológica mais baixa em temperaturas sub ótima e supra ótima. As temperaturas sub e supra ótimas causaram uma redução no desempenho fisiológico das sementes, principalmente nos lotes menos vigorosos. Em geral, o condicionamento osmótico favoreceu um aumento na atividade das enzimas SOD, CAT, POX e APX, principalmente em sementes de baixo vigor expostas às temperaturas sub e supra ótimas. O condicionamento osmótico de sementes de girassol no PEG 6000 a -2,0 MPa, por 8 horas, é eficiente para melhorar o desempenho dos lotes com menos vigor sob estresse devido às temperaturas sub e supra ótimas, favorecendo o aumento da atividade das enzimas do sistema antioxidativo.

Water deficit and high temperature limit agricultural productivity, affecting plant growth, development, and metabolism. Thus, the objective of this study was to evaluate the impact of the interaction between water deficit and temperature increase on cowpea production. The experiment was carried out with the cultivar BRS Rouxinol, in growth chambers, in a 4 × 2 factorial arrangement, being four soil water availability (25; 50; 75 and 100% of field capacity) and two daily temperature regimes (T°1: 20-26-33 °C and T°2: 24.8-30.8-37.8 °C). The increase in water availability favored an increase in shoot and root dry mass. The vegetative stage was prolonged in plants maintained at a temperature regime of 24.8-30.8-37.8 °C. The cowpea yield increased with higher water availability. The water availability of 90% was the one that provided the highest water use efficiency. The 4.8°C increase in air temperature promotes an increase in oxidative stress with lack of synchrony in the antioxidative defense system. The cultivar Rouxinol is sensitive to the increase in air temperature and water deficit. However, even with 100% water availability, there was no seed production with an increase in air temperature. [ABSTRACT FROM AUTHOR]

Copyright of Revista IRRIGA - Brazilian Journal of Irrigation & Drainage is the property of Revista IRRIGA (Brazilian Journal of Irrigation & Drainage) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Caatinga is the property of Revista Caatinga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de Ciências Agrárias is the property of Sociedade de Ciencias Agrarias de Portugal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Numerous factors lead to the use of water with saline levels above those suitable for plant development, resulting in negative consequences on crops. Studies have sought techniques that aim to mitigate such consequences and the use of vitamins is promising, since these compounds improve the development conditions of vegetables. Thus, the study aimed to verify the ability of vitamins to mitigate the deleterious effects of using saline water, applied via irrigation during the formation of cucumber seedlings. Cucumber seeds were subjected to imbibition in three vitamin solutions (100 mg L-1 thiamine; 100 mg L-1 niacin; 50 mg L-1 thiamine + 50 mg L-1 niacin), in addition to two controls, both with water imbibition . After sowing, irrigation was carried out with saline water (100 mM NaCl), for all treatments, except for one of the controls. It was found that irrigation with saline water affected all variables studied, without, however, having a positive effect from the application of vitamins. Thus, it was concluded that the vitamins were not able to mitigate the deleterious effects caused by the application of saline water under the conditions in which the study was carried out and that future studies should be carried out to evaluate different concentrations and forms of application of the vitamins. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)