tailieunhanh - Báo cáo lâm nghiệp: "The effects of lifting on mobilisation and new assimilation of C and N during regrowth of transplanted Corsican pine seedlings. A dual 13C and 15N labelling approach"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí lâm nghiệp đề tài: The effects of lifting on mobilisation and new assimilation of C and N during regrowth of transplanted Corsican pine seedlings. A dual 13C and 15N labelling approach. | Ann. For. Sci. 61 2004 795-805 INRA EDP Sciences 2005 DOI forest 2004080 795 Original article The effects of lifting on mobilisation and new assimilation of C and N during regrowth of transplanted Corsican pine seedlings. A dual 13C and 15N labelling approach Pascale MAILLARDa Didier GARRIOUa Eliane DELÉENSb Patrick GROSSa Jean-Marc GUEHLa a UMR INRA-UHP Écologie et Écophysiologie Forestières Centre INRA Nancy 54280 Champenoux France b Institut de Biotechnologie des Plantes laboratoire de Structure et de Métabolisme des Plantes CNRS Université Paris XI 91405 Orsay Cedex France Received 10 July 2003 accepted 2 April 2004 Abstract - A dual long-term 13C and 15N labelling procedure was used to label C and N reserves of one-year-old Corsican pine seedlings. After labelling seedlings were either submitted to a removal of root tips to simulate a nursery lifting or kept intact before being transplanted into minirhyzotrons parallelepipedal containers allowing root elongation observations and grown for 41 days in a climatized chamber. Applying isotopic dilution equations allowed to assess for regrowth the effects of lifting on the use of C and N either derived from reserves or newly assimilated. Lifting decreased markedly root and shoot growth after transplanting as well as CO2 assimilation rate and stomatal conductance of needles. However both the ratio of needle intercellular ambient CO2 concentration and needle predawn water potential remained unaltered. Lifting also decreased total non-structural carbohydrate TNC concentration at the whole seedling level. Shoot growth began just after transplanting and was supported by old C. Concomitantly a strong decrease in old C and TNC occurred in old roots. A marked N mobilisation was also observed in needles. New root growth occurred 15 days after transplanting and depended less on old C and N than did the new shoot growth. Shoot and root growth were further supported more and more by newly acquired C and N. On day 41 .