Resultados preliminares do efeito da aplicação de um extrato de algas em oliveiras Cobrançosa e Galega

• Autor(a) principal: Mota, M.
• Data de Publicação: 2012
• Outros Autores: Lopes, J.P.S.
• Idioma: por
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.5/5720
• topic: Olea europaea; fruit set; nitrate redutase; glutamine synthetase; biostimulant

Recently, new products designated as biostimulants have become available to farmers, aiming an improvement of the nutrient use and crop performance, namely in fruit set. The application of a seaweed based biostimulant was studied in olive trees ‘Galega’ and ‘Cobrançosa’. The field trial was conducted in an olive orchard near Santarém (Portugal) and biostimulant action was analysed in terms of fruit set and activity of enzymes involved in nitrogen metabolism (nitrate reductase and glutamine synthetase) in leaves and in reproductive organs sampled periodically during flowering and fruit formation. Results showed that the biostimulant application significantly improved fruit set in ‘Galega’ and the enzymatic activity in reproductive organs of ‘Cobrançosa’. It was concluded that the biostimulant effect on enzymatic activity was more expressive in the reproductive organs and in trees grown under suboptimal conditions. These results suggest that in these conditions, the biostimulant may have a stronger beneficial effect on the crop, namely on the nutrien use efficiency (as it happened in ‘Cobrançosa’). However, it is noteworthy that, during spring 2011, when this trial was conducted, heavy rains and strong winds occurred, that might have influenced the results obtained. The contribute of each genotype cannot also be underestimated.