Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài: Drought conditioning improves water status, stomatal conductance and survival of Eucalyptus globulus subsp. bicostata seedlings. | Ann. For. Sci. 63 2006 941-950 INRA EDP Sciences 2006 DOI forest 2006077 941 Original article Drought conditioning improves water status stomatal conductance and survival of Eucalyptus globulus subsp. bicostata seedlings Ana Beatriz GUARNASCHELLla Pablo PRYSTUPAb Jorge Hugo LEMCOFFc a Departamento de Producción Vegetal Facultad de Agronomía Universidad de Buenos Aires Av. San Martín 4453 C1417DSE Buenos Aires Argentina b Departamento de Ingeniería Rural y Uso de la Tierra Facultad de Agronomía Universidad de Buenos Aires cDep. Environ. Physics and Irrigation Institute of Soil Water and Environmental Sciences ARO The Volcani Center PO Box 6 Bet Dagan 50250 Israel Received 15 March 2005 accepted 29 June 2006 Abstract - We investigated the responses of drought preconditioning in three provenances of Eucalyptus globulus subsp. bicostata Maiden Blakely and . Kirkp. seedlings and assessed their effects after transplanting. After one-month moderate drought conditioning treatment seedlings evidenced osmotic adjustment reduction in size leaf area shoot root ratio and stomatal conductance. Inter-provenance variation was found in osmotic adjustment capacity. During the first stages of transplanting period pretreated plants showed improved water status and gas exchange capacity under drought conditions this initial superiority was lost later on. Non-conditioned seedlings also developed morphological and physiological adjustments that allowed them to perform similarly to conditioned plants. Although preconditioning did not favour seedlings growth it was effective in enhancing survival an attribute correlated to shoot root ratio and relative water content. Inter-provenances variation was found in several of the physiological and morphological responses to drought but it was not possible to relate that variation to the dryness of the seed origin site. These results show the advantage of drought preconditioning in Eucalyptus globulus subsp. bicostata which result
