10 research outputs found
Parámetros para la evaluación del impacto de los morteros de revestimiento en las condiciones acústicas de los espacios históricos
Se realiza una evaluación del efecto que produce en el acondicionamiento acústico de recintos históricos los diferentes tiois de morteros utilizado en el revestimiento
Growth of young Tabebuia aurea seedlings under irrigation with wastewater from fish farming
ABSTRACT This study aimed to evaluate the growth of young Tabebuia aurea seedlings irrigated with different concentrations of wastewater from fish farming. The experiment was conducted in a seedling nursery, from June to August 2013. The treatments consisted of five concentrations of wastewater from fish farming diluted in freshwater (0, 25, 50, 75 and 100% of wastewater). Plant height, stem diameter and plant height/stem diameter ratio were evaluated every 15 days to verify the effects of treatments on seedlings growth. At the end of the experiment, individual leaf area, leaf area, leaf dry matter, stem dry matter, root dry matter, total dry matter and Dickson quality index were also evaluated. The reuse of wastewater from fish farming diluted at concentrations of 25 and 50% in freshwater is a viable alternative in the production of Tabebuia aurea seedlings. However, higher concentrations hinder the production of seedlings of this species
Hydropriming as inducer of salinity tolerance in sunflower seeds
ABSTRACT Sunflower is a species with multiple potentialities and its yield can be affected by the presence of soluble salts in the soil, which is common in arid, semi-arid and irrigated regions. The objective of this study was to evaluate the effect of hydropriming as inducer of salinity tolerance in seeds and seedlings of sunflower, hybrid MG305CP. The germination tests were set with four replicates of 50 seeds per treatment, maintained in germinator at 30 ºC for ten days. To simulate salinity, sodium chloride diluted in distilled water was used at electrical conductivities of 0 (control), 4, 8, 12 and 16 dS m-1. On the tenth day, the number of normal seedlings was counted and the length and dry matter of shoots and roots were determined. Seedling fresh matter was used to determine the contents of total chlorophyll, total soluble sugars and proline. The experimental design was completely randomized, in a 2 x 5 factorial scheme (with and without hydropriming and five levels of salinity). Hydroprimed sunflower seeds showed greater vigor expression, with higher number of normal seedlings and faster germination
Hydropriming as inducer of salinity tolerance in sunflower seeds
<div><p>ABSTRACT Sunflower is a species with multiple potentialities and its yield can be affected by the presence of soluble salts in the soil, which is common in arid, semi-arid and irrigated regions. The objective of this study was to evaluate the effect of hydropriming as inducer of salinity tolerance in seeds and seedlings of sunflower, hybrid MG305CP. The germination tests were set with four replicates of 50 seeds per treatment, maintained in germinator at 30 ºC for ten days. To simulate salinity, sodium chloride diluted in distilled water was used at electrical conductivities of 0 (control), 4, 8, 12 and 16 dS m-1. On the tenth day, the number of normal seedlings was counted and the length and dry matter of shoots and roots were determined. Seedling fresh matter was used to determine the contents of total chlorophyll, total soluble sugars and proline. The experimental design was completely randomized, in a 2 x 5 factorial scheme (with and without hydropriming and five levels of salinity). Hydroprimed sunflower seeds showed greater vigor expression, with higher number of normal seedlings and faster germination.</p></div
Salt stress and temperatures on the germination and initial growth of ‘jurema-de-embira’ (Mimosa ophthalmocentra) seedlings
ABSTRACT The objective of this study was to evaluate the effects of salinity on the germination and initial growth of ‘jurema-de-embira’ (Mimosa ophthalmocentra) seedlings at different temperatures. The experiment was installed in a completely randomized design, in a factorial scheme of eight salt concentrations (0; 4.0; 8.0; 12.0; 16.0; 20.0; 24.0 and 28.0 dS m-1) and four temperatures (25, 30, 35 and 20-30 °C) in four replicates of 25 seeds under an 8-h photoperiod in Biochemical Oxygen Demand germinators. The variables analyzed were: germination, germination speed index, shoot and root lengths, and shoot, root and total dry matter. Temperature variation influences the response of ‘jurema-de-embira’ seeds to salinity, and the salt stress is intensified by the increase in temperature. ‘Jurema-de-embira’ is tolerant to salt stress in the germination stage, showing satisfactory germination up to the salinity level 20 dS m-1, at temperatures below 30 °C. The initial growth of ‘jurema-de-embira’ plants is satisfactory up to salinity of 12 dS m-1, at temperatures below 30 °C
Production of Piptadenia stipulacea (Benth.) Ducke seedlings irrigated with fish farming wastewater
ABSTRACT The objective of this study was to evaluate the growth of ‘jurema-branca’ seedlings (Piptadenia stipulacea (Benth.) Ducke.), irrigated with effluent from fish farming in order to meet the nutritional demand in the initial growth stage. The treatments consisted in the dilution of fish farming wastewater in different concentrations (0, 25, 50, 75 and 100%) with supply water. Seeds were sown in 0.9-L polyethylene bag containing a mixture of soil and manure. At 54 days after sowing the shoot length, stem diameter, height/diameter ratio, number of leaves, leaf area, unit leaf area, dry matter of stem, leaves, shoots, roots and total, chlorophyll content index and Dickson quality index were evaluated. The growth of ‘jurema-branca’ seedlings is favored by the dilution of 25% of fish farming wastewater in the supply water. Using up to 25% of the concentration of the fish farming effluent does not significantly affect the dry biomass accumulation in ‘jurema-branca’ seedlings, in relation to the control. The reuse of fish farming wastewater diluted at proportion of up to 25% is a viable alternative to meet the water demand in the production of forest seedlings