No abstract

No abstract

No abstract

The use of silicon in plant cultivation is one of the strategies to mitigate the negative effects of salinity. This study aimed to evaluate the effect of silicate fertilization on the morphophysiological, biochemical and nutritional characteristics of Jatropha curcas L. plants under saline stress. The work was carried out in a greenhouse at the State University of Goiás. The experiment was set up in a completely randomized design in a 5 × 2 factorial arrangement (plants irrigated with salt water with sodium chloride (NaCl) and electrical conductivities equal to 0 dS m-1; 2 dS m-1; 4 dS m-1; 6 dS m-1 and 8 dS m-1 applied at 80 days after emergence (DAE) and absence or presence of silica fertilization of 1 g L-1 with Si applied at 80 and 95 DAE by volume of 30 mL of the solution with the aid of a spray manual), five replicates and experimental plot of one plant per pot. The evaluations were carried out at 130 DAEs. The absence of differences in the concentrations of photosynthetic pigments and visible damages is indicative of the absence of severe toxic effects caused by salinity. The tolerance of Jatropha curcas L. plants to salinity is independent of silicon. The Jatropha curcas L. plant tolerates salinity by minimizing transpiration and remaining hydrated through the water stored in the succulent stem. In addition, the plants control sodium uptake and eliminate toxic compounds through increases in Calcium concentration and antioxidative metabolism respectively.

The objective of the present study was to identify the effect of kinetin on Capsicum frutescens fruit yield. The research was carried out between October 2015 and September 2016 in the experimental field at the State University of Goiás, Brazil. This region has a tropical climate with a dry winter and wet summer. The experiment was conducted in rainy conditions (without irrigation) in a randomized block design with five treatments (plants submitted to 0, 50, 100, 150, 200 and 250 mg L-1 kinetin in volume of 30 ml/plant/application in a total of two applications at a 40-day interval, started at the R 2 reproductive stage), six replications and the plots consisted of two useful plants. The variables stomata density, specific leaf area, stem and canopy diameter, length and width of completely opened leaves did not fit the linear and quadratic regression models in function of the kinetin doses applied. Kinetin increased fruit drain strength and increased productivity of Capsicum frutescens. Plants treated with this cytokinin showed vigorous vegetative growth and significant increases in concentrations of photosynthetic pigments. The use of kinetin in Capsicum frutescens plants is a promising practice in the management of the species because it promotes morphophysiological adjustments in the plant that increase vegetative vigor and fruit yield.

Climatic changes and drought reduced plant growth and development. Brassinosteroids act in maintaining turgor and plant growth, increasing tolerance to water stress. The objective of the present study was to identify the effect of brassinosteroids in reducing stresses caused by water deficit in Jatropha curcas L. plants. The study was carried out in a greenhouse at the State University of Goiás, in a completely randomized block design in a factorial 2 × 5 arrangement (plants submitted to five brassinosteroids concentrations (0, 2, 4, 8, 16 mg L-1) and two levels of daily water supply (50% and 100% evapotranspiration) six replications and the plot consisted of one useful plant. A 10 mL volume of the hormone was applied 30 days after emergence and 20 mL at 60 days after emergence, totaling 30 ml. The water deficit was imposed at 70 days after emergence and the evaluations were made at 100 d after emergence. Under water deficit, production increased of reactive substances that damage membranes and proteins, but brassinosteroids played an important role in mitigating the deleterious effects of water deficit on J. curcas plants by acting as an elicitor in activating photoprotection mechanisms that increased vegetative growth and maintained membrane integrity. The antioxidant and growth machinery activation reached maximum points at the 8 mg L-1 brassinosteroids concentration and even higher concentrations

No abstract