Ferulic acid uptake by soybean root in nutrient culture

Ferulic acid uptake by soybean root in nutrient culture was investigated by the depletion method at different concentrations, temperatures and pH. Results showed that soybean roots absorbed this compound at greater rates in the concentrations between 0.05-mM and 1.0-mM and it was concentration dependent. Ferulic acid uptake was unaffected at pH 4.5 or 6.0 but reduced at pH 7.0. At pH 6.0, uptake rates decreased significantly with increasing temperature of nutrient solution

Ferulic acid depletion by cultured soybean seedlings under action of glucose and methionine

Cultured soybean seedlings were used to investigate how glucose or methionine influenced depletion of ferulic acid. Three-day-old seedlings were grown in hydroponic solution containing ferulic acid plus glucose or methionine, and the level of the phenolic acid were monitored in the nutrient culture. The results showed that ferulic acid depletion was more rapid in the presence of those compounds. After 6 h, the increase caused by glucose (0.01 and 0.05 mM) was more pronounced than methionine in the same concentrations. On the other hand, methionine (0.1 and 0.2 mM) increased depletion more significantly than glucose. Results suggested that both compounds might to increase the allelopathic effects of ferulic acid in the seedlings

Efeitos individuais e interativos de ácidos fenólicos sobre a peroxidase e peroxidação lipídica em raízes de soja, Glycine max (L.) Merr. (Leguminosae-Faboidae)

The purpose of the present work was to evaluate the individual and simultaneous effects of p-coumaric acid (p-CA) and p-hydroxybenzoic acid (p-HB) on soybean, Glycine max (L.) Merr. (Leguminosae-Faboidae) peroxidase (POD, EC 1.11.1.7), lipid peroxidation (LP) and root growth. Three-day-old seedlings were cultivated in nutrient solution containing p-CA or p-HB (0.5 and 1.0 mM) or equimolar mixtures for 24 hours. Individually, the two allelochemicals decreased root length (RL), root fresh weight (FW), root dry weight (DW), increased soluble POD and cell wall (CW)-bound POD but did not affect LP. The joint effects of these compounds were lower than the sum of the effects of each one tested separately. The results indicate that the mixtures of these allelochemicals can affect growth of soybean roots in an antagonistic manner.O propósito do presente trabalho foi avaliar os efeitos individuais e simultâneos dos ácidos p-cumárico (p-CA) e p-hidroxibenzóico (p-HB) sobre a peroxidase (POD, EC 1.11.1.7) de soja Glycine max (L.) Merr. (Leguminosae-Faboidae), peroxidação lipídica (LP) e crescimento das raízes. Plântulas de três dias de desenvolvimento foram cultivadas, durante 24 horas, em solução nutritiva contendo p-CA ou p-HB (0,5 e 1,0 mM) ou misturas equimolares. Individualmente, os dois aleloquímicos diminuíram o comprimento das raízes (RL), a biomassa fresca das raízes (FW), a biomassa seca das raízes (DW), aumentaram a POD solúvel e POD ligada à parede celular mas não afetaram a LP. Os efeitos simultâneos desses compostos foram menores que a soma dos efeitos de cada um, testado separadamente. Os resultados indicam que as misturas desses aleloquímicos podem afetar o crescimento das raízes de soja de maneira antagônica

Carbohydrate and lipid status in soybean roots influenced by ferulic acid uptake

The objective of this research was to investigate how the allelochemical ferulic acid affects the carbohydrate and lipid contents of soybean roots cultivated in nutrient culture. The results presented revealed that ferulic acid has significant effects on carbohydrates by the increase in xylose, fructose and sucrose and decrease in glucose, after 24 h treatment of roots. Ferulic acid increased the contents of saturated and unsaturated fatty acids of the polar and non-polar lipid fractions. The results may contribute as additional data to explain allelopathic effects caused by ferulic acid

Ferulic acid depletion by cultured soybean seedlings under action of glucose and methionine

Cultured soybean seedlings were used to investigate how glucose or methionine influenced depletion of ferulic acid. Three-day-old seedlings were grown in hydroponic solution containing ferulic acid plus glucose or methionine, and the level of the phenolic acid were monitored in the nutrient culture. The results showed that ferulic acid depletion was more rapid in the presence of those compounds. After 6 h, the increase caused by glucose (0.01 and 0.05 mM) was more pronounced than methionine in the same concentrations. On the other hand, methionine (0.1 and 0.2 mM) increased depletion more significantly than glucose. Results suggested that both compounds might to increase the allelopathic effects of ferulic acid in the seedlings

Root Growth and Enzymes Related to the Lignification of Maize Seedlings Exposed to the Allelochemical L-DOPA

L-3,4-Dihydroxyphenylalanine (L-DOPA) is a known allelochemical exuded from the roots of velvet bean (Mucuna pruriens L. Fabaceae). In the current work, we analyzed the effects of L-DOPA on the growth, the activities of phenylalanine ammonia-lyase (PAL), tyrosine ammonia-lyase (TAL), and peroxidase (POD), and the contents of phenylalanine, tyrosine, and lignin in maize (Zea mays) roots. Three-day-old seedlings were cultivated in nutrient solution with or without 0.1 to 2.0 mM L-DOPA in a growth chamber (25°C, light/dark photoperiod of 12/12, and photon flux density of 280 μmol m−2 s−1) for 24 h. The results revealed that the growth (length and weight) of the roots, the PAL, TAL, and soluble and cell wall-bound POD activities decreased, while phenylalanine, tyrosine, and lignin contents increased after L-DOPA exposure. Together, these findings showed the susceptibility of maize to L-DOPA. In brief, these results suggest that the inhibition of PAL and TAL can accumulate phenylalanine and tyrosine, which contribute to enhanced lignin deposition in the cell wall followed by a reduction of maize root growth

Growth and root lignification of susceptible and glyphosate-resistant soybean = Crescimento e lignificação de raízes de soja suscetível e resistente ao glifosato

Glyphosate resistance is conferred to soybean (Glycine max L. Merril) by incorporating a gene encoding a glyphosate-insensitive enzyme (CP4-EPSP synthase) that acts in the shikimate/chorismate pathway, an important metabolic route in the lignification process. The aim of this work was to investigate the root growth and lignin contents of susceptible (CD 201 and OC 14) and glyphosate-resistant (CD 214RR and CD 213RR) soybean cultivars. To this end, three-day-old seedlings were cultivated in half-strength Hoagland nutrient solution (pH 6.0) in a growth chamber (25‹C, 12-h photoperiod, irradiance of 280 ƒÊmol m-2 s-1) for 24 to 96 hours. The results revealed that glyphosate-resistant (CD 213RR and CD 214RR) cultivars showed high root growth when compared to the conventional (OC-14 and CD 201) cultivars. CD 213RR showed high root lignin content and reduced root weight compared to the conventional (OC 14) cultivar, although CD 214RR and CD 201 did not follow the same trend. Based on these results, it is possible to conclude that (1) the different form of EPSP synthase encoded in RR soybean may interfere in phenylpropanoid pathway and further in lignin biosynthesis, and (2) other genetic characteristics inherent to each cultivar may affect roots lignincontent in soybean seedlings since lignification in CD 214 RR was not affected of similar manner than cultivar CD 213 RR.A resistencia ao glifosato e conferida a soja (Glycine max L. Merrill) pela incorporacao de um gene que codifica a enzima CP4-EPSP sintase, uma variante da EPSP sintase, insensivel ao glifosato, que atua na via do chiquimato/corismato, importante rota metabolica envolvida na lignificacao. O objetivo deste trabalho foi o de investigar o crescimento e os teores de lignina nas raizes de cultivares de soja, suscetiveis (CD 201 e OC 14) e resistentes (CD 214RR e CD 213RR) ao glifosato. Para isso, plantulas com tres dias de desenvolvimento foram cultivadas em solucao nutritiva de Hoagland, meia-forca (pH 6,0), em camara de crescimento (25‹C, fotoperiodo de 12 h, irradiancia de 280 ƒÊmol m-2 s-1) de 24 a 96h. Os resultados revelaram que as cultivares resistentes ao glifosato (CD 213RR e CD 214RR) apresentaram elevado crescimento das raizes quando comparadas com as cultivares convencionais (OC-14 e CD 201). A cultivar CD 213RR apresentou altos teores de lignina e reduzido crescimento das raizes em comparacao com a cultivar convencional (OC 14). O mesmo nao foi observado nas cultivares CD 214RR e CD 201. Com base nos resultados, e possivel concluir que (1) uma forma diferente de EPSP sintase pode interferir na via de fenilpropanoides e, posteriormente, na sintese de lignina, e (2) outras caracteristicas geneticas inerentes a cada cultivar pode afetar os conteudos de lignina nas raizes, haja vista que a lignificacao na cultivar CD 214RR nao foi afetada de similar maneira que na cultivar CD 213RR

α-Tocopherol levels in natural and artificial aging of soybean seeds - doi: 10.4025/actasciagron.v34i3.12660

Tocopherols are well known constituents of vitamin E, and the main antioxidants in soybean. Are natural antioxidants and stabilizers that can inhibit lipid degradation, reducing non-enzymatic oxidation of these compounds during storage of seeds, germination and initial development of seedlings. The objective of this work was to determine the level of α-tocopherol in four soybean seeds cultivars naturally and artificially aged. Seeds of four soybean cultivars stored from 0 to 180 days in a dry chamber (natural aging) and subjected to high temperature and humidity (artificial aging) were analyzed for α-tocopherol content. The quantification of α-tocopherol in the soybean seeds was performed by high performance liquid chromatography (HPLC) combined with the Soxhlet extraction method. Significant differences in α-tocopherol levels in seeds were observed for all cultivars and storage times. The α-tocopherol contents of the soybean seeds showed linear correlations with an increasing period of storage for all the cultivars studied. However, the artificially aged seeds had a higher content of α-tocopherol than those naturally aged

ETHEPHON AND CALCIUM CHLORIDE, A COMBINATION THAT IMPROVES SKIN COLOR OF ‘RUBI’ TABLE GRAPE

ABSTRACT ‘Rubi’ table grape has wide acceptance of the consumer market due to its affordable price and attractive color as a function of the accumulation of anthocyanins. However, environmental conditions do not always favor the suitable accumulation of these pigments, resulting in commercial devaluation and nutritional depreciation of fruits. Thus, the present study aimed to investigate the effect of application of different ethephon concentrations, associated or not with CaCl2 application, on the skin color and quality of ‘Rubi’ grape berries. First, specific traits of berries treated with 0, 200, 400, 600, 800 mg L-1 ethephon associated with 1.5% CaCl2 solution were evaluated and pH, titratable acidity (TA), soluble solids (SS), berry firmness, total and reducing soluble sugars, and anthocyanin and flavonol levels were analyzed. This first stage of evaluation revealed no changes in total sugar levels, firmness, SS, TA, SS/TA ratio, and flavonol levels, while changes were detected regarding reducing sugar and anthocyanin levels. Thus, in the second stage, the following variables were evaluated: SS, TA, reducing sugar levels, anthocyanin levels, phenylalanine ammonia lyase (PAL) and glutathione S-transferase (GST) activity of ‘Rubi’ grape berries treated with 0, 200, 400, 600, 800 mg L-1 ethephon, associated or not with 1.5% CaCl2 solution. The results of the present study indicate that ethephon associated with CaCl2 can contribute to improve the post-harvest quality of ‘Rubi’ grape, since this association increased the accumulation of anthocyanins due to the higher activity of PAL and GST, related to biosynthesis and storage of antocyanins, respectively, and increased the levels of reducing sugars (at low ethephon concentrations), not changing other quality aspects. Therefore, a single ethephon application from 200 mg L-1 associated with the application of 1.5% CaCl2 at the final ripening stage, when bunches present from 30 to 50% skin color coverage, was sufficient to produce satisfactory results regarding skin color improvement of ‘Rubi’ grape berries