tailieunhanh - Báo cáo khoa học: "Osmotic adjustment in Pinus pinaster cuttings in response to a soil drying cycle"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: Osmotic adjustment in Pinus pinaster cuttings in response to a soil drying cycle. | Ann. For. Sci. 59 2002 795-799 INRA EDP Sciences 2002 DOI forest 2002067 795 Note Osmotic adjustment in Pinus pinaster cuttings in response to a soil drying cycle Anne Nguyen-Queyrensa Paulo Costatb Denis Loustaua and Christophe Plomionb aLaboratoire Écophysiologie et Nutrition Institut National de la Recherche Agronomique Unite de Recherches Forestieres de Bordeaux-Cestas Domaine de l Hermitage Pierroton Gazinet 33611 France bLaboratoire Génétique et Amelioration des Arbres Forestiers Institut National de la Recherche Agronomique Unite de Recherches Forestieres de Bordeaux-Cestas Domaine de l Hermitage Pierroton Gazinet 33611 France Received 3 December 2001 accepted 19 February 2002 Abstract - Two-year-old cuttings of five genotypes of maritime pine Pinus pinaster Ait. were subjected to a four-month treatment of slowly decreasing water availability in pots. Final predawn needle water potential varied from to MPa and was negatively correlated with plant size. Osmotic adjustment was estimated as the slope of the regression line fitted between relative water content RWC and osmotic potential Tn assessed during the drying cycle and as the value of the relative water content for a given level of Tn . Tn MPa . Under the experimental conditions the genotypes showed a high capacity for osmotic adjustment in needles and one genotype distinguished itself with a smaller capacity. The results are discussed in terms of protocol and interpretation when ranking genotypes for osmotic adjustment. osmotic adjustment drought Pinus pinaster Résumé - Ajustement osmotique de boutures de Pinus pinaster en réponse à un dessèchement du sol. Des boutures issues de 5 genotypes de pin maritime Pinus pinaster Ait. et âgées de 2 ans ont été soumises en pot à un arrosage decroissant lentement au cours du temps pendant 4 mois. Les valeurs finales de potentiel hydrique foliaire de base variaient entre -0 82 et -1 48 MPa et étaient négativement corrélées à la taille du