Soluções nutritivas para cultivo e produção de frutanos em plantas de Vernonia herbacea

Abstract

Pesq. agropec. bras., Brasília, v.40, n.9, p.911-917, set. 2005 Soluções nutritivas para o cultivo de Vernonia herbacea 911 Soluções nutritivas para cultivo e produção de frutanos em plantas de Vernonia herbaceaGeraldo Rogério Faustini Cuzzuol (1) , Maria Angela Machado Carvalho (2) , Lilian Beatriz Penteado Zaidan (2) e Pedro Roberto Furlani , foi comparada com a de Hoagland nas forças iônicas de 50%, 100% e 200%. Foram realizadas duas avaliações para análise de crescimento e conteúdo de frutanos. As plantas não sobreviveram até os dois meses na solução de Hoagland 200%. A solução Vernonia diluída duas vezes (50%) foi a mais eficiente para o incremento de massa seca dos rizóforos e produção de frutanos por planta. Maior crescimento da parte aérea foi verificado nas soluções de Hoagland e Vernonia 100%. Em comparação com a solução de Hoagland, a solução Vernonia é mais pobre em macronutrientes, confirmando a hipótese de que plantas adaptadas a solos oligotróficos são menos exigentes em nutrientes minerais.Termos para indexação: nutrição mineral, Asteraceae, cerrado. . Its effect on plants was compared to that of Hoagland solution, both with different ionic strengths, 50%, 100% and 200%. The effect of the solutions on plant growth and fructan content was evaluated twice in a six-month period. Plants did not survive up to two months, when cultivated in 200% Hoagland solution. The 50% Vernonia solution was the most effective for rhizophore biomass increase and fructan production per plant. Growth of aerial organs was promoted in 100% Hoagland and Vernonia solutions. Compared to Hoagland, Vernonia solution contains less macronutrients, which confirms the hypothesis that plants adapted to the oligotrophic soils of the cerrado, as V. herbacea, demand less mineral nutrients to achieve full growth. Nutrient solutions for plant growth and fructan production in Vernonia herbacea

Effects of elevated CO2 concentration and water deficit on fructan metabolism in Viguiera discolor Baker

“…Half of the plants received ambient CO 2 (380 ± 20 ppm) and half received elevated CO 2 (760 ± 50 ppm) provided from a cylinder containing 99.8% CO 2 . During 21 days of acclimation, plants received 100 ml Vernonia nutrient solution per week (Cuzzuol et al. 2005) and were further irrigated with water to keep soil moist.…”

Growth, photosynthate partitioning and fructan accumulation in plants of Vernonia herbacea (Vell.) Rusby under two nitrogen levels

“…The chemical composition of leaves of V. herbacea was determined in the Laboratório do Centro de Solos e Recursos Agroambientais do Instituto Agronômico de Campinas (IAC) and a specific nutrient solution was elaborated to supply adequate nitrogen requirement as previously determined by Cuzzuol et al (2005) (Hoagland and Arnon, 1938) and the pH was adjusted to 5.5-6.0 with 1N KOH. Plants were separated in two groups that received 100 mL of one of the above solutions each week.…”

“…However, more recently Cuzzuol et al (2003) showed that in a narrow range of low concentrations, nitrogen promoted growth and inhibited fructan accumulation and plant productivity in field grown plants, whereas the opposite was found when higher nitrogen concentration was supplied. The chemical composition of leaves of V. herbacea allowed us to define nitrogen requirement of these plants (Cuzzuol et al, 2005).…”

Fructan production in Vernonia herbacea (Vell.) Rusby is related to adequate nitrogen supply and period of cultivation

“…Previous results with V. herbacea showed that the ideal nitrogen concentration for plant growth is 10.7 mmol L -1 N-NO 3 -and that 1.3 mmol L -1 N-NO 3 -provides a limiting growth condition (Cuzzuol et al 2005a). Therefore, the use of this N-limited concentration satisfies the criteria established for the study of a specific stress factor.…”

“…Rusby (Herbarium number: SP169567) were obtained and cultivated as described by Cuzzuol et al (2005b). Plants received, weekly, 100 mL of a specific nutrient solution containing 10.7 mmol L -1 N-NO 3 -, elaborated to supply adequate nitrogen required by V. herbacea as previously determined by Cuzzuol et al (2005a). After twelve months of growth, half of the plants continued to receive the same solution (control plants) while the other half received an N-limited nutrient solution (1.3 mmol L -1 N-NO 3 -), according to Cuzzuol et al (2005a).…”