Absorção de nutrientes e resposta à adubação em linhagens de tomateiro

Abstract

Palavras-chave: Solanum lycopersicum, DRIS, nutrição de plantas, melhoramento genético. ABSTRACT Nutrient uptake and response to fertilization of tomato inbred linesTwenty nine processing tomato inbred lines were evaluated for their efficiency in nutrient uptake and in their response to fertilization. Two field assays were carried out at Embrapa Hortaliças, Brazil, with distinct fertilization dosages in 2006. In the first assay 1/3 of the total fertilization was applied when compared with the second assay. The experiments were conducted using a completely randomized design with three replications. The criteria to rank the inbred lines in both assays were the DRIS (Diagnosis and Recommendation Integrated System) index value and fruit yield. The critical values in order to distinguish efficient versus non-efficient as well as responsive versus non-responsive inbred lines were the average increase in both DRIS index value and fruit yield. Differences were detected among inbred lines for the uptake efficiency for all nutrients and for response to fertilization. The inbred lines 03, 40, 09 and 22 were classified as responsive to fertilization and efficient in N uptake; the lines 03, 04, 09, 13, 15 and 29 were for P; 03, 05, 10, 21, 22, 25 and 27 for K, 05, 10, 21, 22, 25, 27 and 29 for Ca; 04, 13, 15, 27 and 29 for S and B; 03, 05, 09, 10 and 27 for Cu. The inbred lines with the best performance were 27 in relation to nutrient absorption, and the lines 03, 04, 05 and 29 in relation to fertilization response.

Nitrogen use efficiency and forage production in intraspecific hybrids of Paspalum notatum Flüggé

“…No difference in NUE was observed between genotypes and no Genotype × N interaction was recorded, in any year. A similar NUE between genotypes may indicate low genetic divergence for this characteristic, since variability in plant species usually provides differences in the nutrient absorption capacity (Oliveira et al, 2009). Usually, morphophysiological characteristics, such as the surface area of the roots, the size of the root system or the physiology of absorption and solubilization of initially non-soluble forms in the rhizosphere are determinants for the nutrient absorption efficiency (Samal et al, 2010).…”

Sintomas visuais de deficiência de macronutrientes e boro em coentro

“…Pizetta et al (2005) observaram aumento na produtividade de brócolis e repolho em resposta à adubação com boro. Os nutrientes minerais desempenham funções essenciais e específicas, portanto sua deficiência ou toxidez é observada através de quadros sintomatológicos, muitas vezes característicos para cada nutriente, sendo dependente da cultivar estudada e dos fatores ambientais (Oliveira et al, 2009). A solução nutritiva e a técnica do elemento faltante são utilizadas na pesquisa cientí-fica principalmente para obtenção de informações sintomatológicas de carência ou toxidez de determinado nutriente nas plantas, auxiliando no aperfeiçoamento do sistema de produção (Andriolo et al, 2002;Alves et al, 2008).…”

Absorção de nutrientes em genótipos de girassol

“…Além disso, a variabilidade de comportamento entre espécies vegetais, e mesmo entre genótipos, geralmente proporciona diferenças na capacidade de absorção de nutrientes (Oliveira et al 2009). Logo, como a exigência entre cultivares da mesma espécie é distinta, é comum observar acúmulo diferenciado de nutrientes e fitomassa, assim como variações de caracteres agronômicos (altura de plantas, diâmetro de caule, número de folhas, etc.…”