Metabolismo do nitrog?nio e atividade de bombas de pr?tons em ra?zes transg?nicas com ?cido h?mico e simbiose micorr?zica arbuscular

• Autor(a) principal: Lima, Wallace Lu?s de
• Data de Publicação: 2008
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFRRJ
• Texto Completo: https://tede.ufrrj.br/jspui/handle/tede/323
• topic: subst?ncias h?micas; absor??o radicular; ra?zes em cabeleira; humic substances; root absorption; hairy roots; Agronomia

The objective of this study was to evaluate biochemical and morphologic aspects involved in the interaction nitrogen-mycorrhiza-humic acid (N-AMFs-HA) in transformed roots of basil (Ocimum basilicum L.) and clover (Trifolium repens L.) "in vitro". The effect of different concentrations of humic acid was evaluated, extracted of vermicompost of bovine manure, added to the root medium. The influence of different concentrations from N-NO3 - was also evaluated (0.5 and 5.0 mmoles L-1) as the interaction of these factors with arbuscular mycorrhizal fungi (AMFs) symbiosis. The following experiments were developed: I) Production and characterization of humic acid; II) calibration of the curve for humic acids response with six concentrations (10, 20, 40, 80, 160 mg C L-1 and control without HA) in the development of transformed roots of basil after 15, 30 and 45 days of growth (DAR) accomplished through digital images; III) evaluation of the six concentrations of HA in the 6 and 9 following days, in basil and clover roots; IV) Influence of N-NO3 - (0.5 and 5.0 mmoles L-1) in roots of basil and clover after period of 72 hours in solution without N and the evaluations accomplished to the 0, 12, 24 and 48 following hours; V) Influence of the interaction humic acid (10, 20 mg C L-1 and control without HA), and N-NO3 - (0.5 and 5.0 mmoles L-1) in basil and clover roots to the 6, 9 and 15 to DAR; VI) Influence of the interaction humic acid (20 mg C L-1 and control without HA), N-NO3 - (0.5 and 5.0 mmoles L-1) and arbuscular mycorrhiza Glomus clarum in basil and clover roots to the 30 DAR, with the activity of the proton pumps and the N metabolism (in the experiment III, IV, V and VI). It was observed that the concentration of 20 mg C L-1 showed the best results in the development of the roots and higher concentrations of 40 mg C L-1 didn't provide significant induction in the development of roots. The HA influenced, positively, the activity of P-H+-ATPases, V-H+-ATPases and H+-PPases and N metabolism in both roots in all experiments. The roots presented larger influence of the interaction HA - NO3 - in the evaluation after six days of contact for all the accomplished evaluations, which resulted in larger levels of N-NO3 - and N-amino inside the vegetable cells specially after 9 days. The roots submitted to the treatments with humic acids (10 and 20 mg C L-1), in two concentrations of nitrogen presented the largest benefits in the activity of the proton pumps and in N metabolism in all the evaluation periods. The addition of 20 mg C L-1 stimulated the colonization of Glomus clarum and also in the activity of the proton pumps (P-H+-ATPase and H+-PPase) and in the N metabolism in the treatments with low concentrations of nitrogen (0.5 mmoles L-1 of N-NO3 -).