Spermine reduces the harmful effects of salt stress in Tropaeolum majus.

Flowers, leaves, fruits and buds of Tropaeolum majus are used for ornamental, medicinal and food purposes. However, salt stress limits the development and productivity of T. majus due to biochemical, physiological and anatomical disturbances. Polyamine application is an alternative for mitigating the harmful effects of salt stress. Thus, the objective of this work was to evaluate the effects of spermine application in T. majus grown under salt stress. The experiment was carried out in a completely randomized design, in a 3 × 2 factorial scheme, with 0, 40 mM (moderate salt stress) and 80 mM (severe salt stress) NaCl, and 0 and 1 mM spermine, and with five replicates. Growth (plant height, stem diameter, number of leaves, number of flowers, number of buds, leaf dry mass, stem dry mass and flower dry mass), gas exchange (gs, A, E, Ci and WUE), relative water content, contents of free amino acids, phenolic compounds, reducing and non-reducing sugars, lipid peroxidation and enzymatic activities (CAT, POD and APX) were evaluated. Spermine application decreased the harmful effects of salt stress on the growth and gas exchange and increased flowering in T. majus. Furthermore, the relative water content of T. majus increased under severe salt stress conditions. Spermine application reduced the contents of total phenolic compounds, free amino acids, reducing sugars and non-reducing sugars on leaves of T. majus. Spermine application increased CAT and POD activities in plants under severe salt stress and POD and APX in plants under moderate salt stress.

Ideal temperature and storage period for commercial potato cultivars selected for frying / Temperatura e período de armazenamento ideais para cultivares comerciais de batata selecionadas para fritura

ABSTRACT: Potatoes for industrial processing must have high dry matter, low sugar and free from damage or disease. The objective was to determine the ideal temperature and storage period of commercial cultivars for frying. Tubers of Asterix and Cronos cultivars were stored in a cold chamber (Gallant CMC4 Premium) inside plastic boxes at 6 and 8 °C with 85 to 95% humidity for 180 days. Accumulated mass loss (PMA), alcohol insoluble solids (SIA), total soluble sugars (AST), non-reducing sugars (ANR), reducing sugars (AR), polyphenoloxidase activity (PPO) and enzymatic and non-enzymatic browning were analyzed. The PMA of Asterix at 6 and 8 ºC and Cronos at 6 °C was higher. The SIA of both cultivars stored at 6 ºC were lower and AST, AR and ANR higher. Those parameters of Cronos and Asterix did not differ between temperature or storage period. The browning was greater in the fried sticks of Asterix and Cronos stored at 6 ºC (4 to 5) for 60 and 90 days and at 8 °C (2 to 3) for 180 days, respectively. The ideal temperature and storage period for Asterix and Cronos cultivars is 8 ºC for a maximum of 120 days due to non-enzymatic browning.

RESUMO: As batatas destinadas ao processamento industrial devem ter alto teor de matéria seca, baixo teor de açúcar e estar livre de danos ou doenças. O objetivo foi determinar a temperatura e o período de armazenamento ideais para cultivares comerciais para fritura. Os tubérculos das cultivares Asterix e Cronos foram armazenados em caixas de plástico a 6 e 8 °C com umidade de 85 a 95% por 180 dias. As perdas de massa acumulada (PMA), sólidos insolúveis em álcool (SIA), açúcares solúveis totais (AST), açúcares não redutores (ANR), açúcares redutores (AR), atividade de polifenoloxidase (PPO) e escurecimento enzimático e não enzimático foram analisadas. A PMA de tubérculos da cultivar Asterix a 6 e 8 ºC e a da cultivar Cronos, armazenadas a 6 °C foram maiores. Os teores de SIA foram menores e os de AST, AR e ANR maiores nos tubérculos de ambas as cultivares armazenadas a 6 ºC. A temperatura e o período de armazenamento não afetaram as cultivares Cronos e Asterix. O escurecimento foi maior nos palitos fritos das cultivares Asterix e Cronos armazenados a 6 ºC (4 a 5) por 60 e 90 dias e a 8 °C (2 a 3) por 180 dias, respectivamente. O período ideal de temperatura e armazenamento para as cultivares Asterix e Cronos é de 8 ºC por, no máximo, 120 dias devido ao escurecimento não enzimático.

Green leaves and seeds alcoholic extract controls Sporobulus indicus germination in laboratory conditions.

High seed production makes Sporobolus indicus var. pyramidalis a difficult to control invasive grassland plant. The objective of the present study was to investigate the bioactivity of Cyperus rotundus, Phyllanthus tenellus and Ricinus communis green leaf extracts and of Carica papaya seeds on S. indicus germination without breaking dormancy, simulating the field conditions. The ethanolic extract bioactivity of C. rotundus, P. tenellus, R. communis green leaves and C. papaya seeds, at concentrations of 25, 50 and 75% in S. indicus germination was evaluated. Carotenoids, flavonoids, soluble phenolic compounds and total tannins were quantified in the extracts. The chemical component concentrations varied between alcoholic extracts. The P. tenellus extracts at all dilutions and those of R. communis and C. papaya at 75% completely suppressed S. indicus seed germination at five and ten days which can be attributed to their high tannin concentration, total phenolic compounds and flavonoids.

Genetic divergence of native palms of Oenocarpus distichus considering biometric fruit variables.

Oenocarpus distichus presents economic, ecological, and dietary potential for pulp market processed in natura. Germplasm conservation and genetic improvement depend on genetic divergence studies. The objective was to quantify genetic divergence in a native population of O. distichus genotypes based on fruit biometrics. The fruit length and width, fruit mass, pulp and seed, pulp and almond thickness, and pulp yield per fruit were evaluated. All fruit biometric characteristics of O. distichus palms show genetic variability. Genetic variations among genotypes are essential for predicting heredity and heterosis, which are essential for improving O. distichus production. Pulp yield and seed mass were negatively correlated. Almond thickness and pulp, seed mass and transverse diameter were positively correlated. Genetic distances between pair of genotypes ranged from 0.07 to 48.10 with three genetically distinct groups. The seed mass, almond thickness and transverse diameter contributed to genetic divergence. Heritability estimates the genetic control that can be obtained from O. distichus germplasm. Correlations between the variable pair reduce the evaluation effort and the resources to measure the genotype allocations in heterogeneous groups presenting high genetic variability. This makes it possible to select individuals for hybridization programs with F1 generation gains. Correlation and relative contribution networks, based on relationships graphical between fruit biometric characteristics, allow the variables selection with less effort and fewer measurements. O. distichus fruit biometric characters are efficient to quantify genetic divergence between genotypes.

Geotechnology in the analysis of forest fragments in northern Mato Grosso, Brazil.

Pasture implantation fragments and reduces the Amazonian forest area. The objective was to quantify landscape changes in 1985, 2000 and 2015 in northern Mato Grosso, Brazil. The study was carried out in three scenes obtained by the LANDSAT satellite of a microbasin (2742.33 ha) in the municipality of Alta Floresta. Forest, water bodies, pasture and exposed soil were the thematic classes determined to e mapping the land use evolution. The edge, density and shape indexes of the fragments were measured. Normalized vegetation difference (NDVI) values were high in 1985. Land use and occupation over 15 years (1985-2000) reduced forest cover by 69.8%, but it increased by 1.7% over the next 15 years (2000-2015). The number of exposed soil patches increased between the periods, but the total area and number of the patches of the forest fragments decreased. The high values of NDVI in 1985 showed vegetated areas with high density. Reducing forest cover decreases the size of the fragments, increases the isolation and the number of soil patches exposed. The mapping of land use showed a reduction of the Amazon forest in the microbasin in the north of Mato Grosso, in the years 2000 and 2015 compared to 1985.

Ethylene, 1-methylcyclopropene and silver thiosulfate on the post-production of ornamental pepper / Etileno, 1-metilciclopropeno e tiossulfato de prata na pós-produção de pimenteiras ornamentais

ABSTRACT: Species from Capsicum genus are used for different purposes and in more recent years as ornamental potted plant. Despite the increased commercial importance, there are only a few studies on the environmental factors affecting the post-production shelf life of these ornamental plants. The presence of ethylene induces various responses on potted peppers, reducing the shelf life of sensitive cultivars. This study aimed to evaluate the effects of ethylene and the inhibitors of ethylene action, 1-methylcyclopropene (1-MCP) and silver thiosulfate (STS) on the shelf life of potted 'Calypso' and 'MG 302' peppers. Cultivar 'MG 302' showed intermediate sensitivity to ethylene action, while the cultivar 'Calypso' showed complete abscission of leaves when exposed to ethylene. In both cultivars, treatment with STS + Ethylene presented symptoms of phytotoxicity in plants, while treatment with 1-MCP + Ethylene was effective in delaying senescence and abscission for the cultivar 'MG 302', while cultivar 'Calypso' showed abscission similar to control plants. Plants treated with STS showed the longest durability when compared to the other treatments, about six days for 'Calypso' and 18 days for 'MG 302'. Nevertheless, plants treated with 1-MCP also exhibited good shelf life, about six days for 'Calypso' and nine days for the 'MG 302'. Although the treatment with STS was more efficient on the plants shelf life, did not completely block the action of ethylene and exhibited some phytotoxicity, while the treatment with 1-MCP had good efficiency without inducing any toxicity.

RESUMO: Espécies do gênero Capsicum estão sendo usados para diversas finalidades e nos últimos anos como planta ornamental de vaso. Apesar da crescente importância comercial, há poucos estudos sobre os fatores ambientais que afetam a sua vida útil de pós-produção destas plantas ornamentais. A presença de etileno induz várias respostas em pimenteiras em vasos, reduzindo a vida útil de prateleira de cultivares sensíveis. Este estudo teve como objetivo avaliar os efeitos do etileno e inibidores da ação do etileno, 1-metilciclopropeno (1-MCP) e tiossulfato de prata (STS) sobre a vida útil de vaso de pimenteiras das cultivares 'Calypso' e 'MG 302'. A cultivar 'MG 302' apresentou sensibilidade intermediária a ação do etileno, enquanto a cultivar 'Calypso' apresentou abscisão completa das folhas quando exposta ao etileno. Em ambas as cultivares, o tratamento STS + Etileno mostrou sintomas de fitotoxicidade nas plantas. O tratamento com 1-MCP + Etileno foi eficaz em retardar a senescência e abscisão apenas para a cultivar 'MG 302', enquanto a cultivar 'Calypso' mostrou abscisão foliar semelhante as plantas controle. Plantas tratadas com STS mostraram maior durabilidade quando comparadas aos outros tratamentos, cerca de seis dias para 'Calypso' e dezoito dias para 'MG 302'. No entanto, as plantas tratadas com 1-MCP também exibiram boa vida útil de prateleira, cerca de seis dias para 'Calypso' e nove dias para a 'MG 302'. Embora o tratamento com STS tenha sido mais eficiente na vida de prateleira das plantas, não bloqueou completamente a ação do etileno e apresentaram algum fitotoxicidade, enquanto o tratamento com 1-MCP teve boa eficiência sem induzir qualquer toxicidade.