tailieunhanh - Báo cáo khoa học: "Effects of exposure to air on planting stress in red oak seedlings"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: "Effects of exposure to air on planting stress in red oak seedlings". | 395 Ann Sci For 1997 54 395-401 Elsevier Inra Note Effects of exposure to air on planting stress in red oak seedlings s Girard 2 A Clement3 B Boulet-Gercourt2 JM Guehl Equipe bioclimatoiogie et écophysiologie forestieres. Centre Inra de Nancy 54280 Champenoux 2 institut pour le développement forestier 23 avenue Bosquet 75007 Paris 3 Éqtiipe sol et nutrition Centre Inra de Nancy 54280 Champenoux France Received 22 August 1996 accepted 9 January 1997 Summary - One-year-old bare-root red oak Quercus rubra L seedlings were lifted in March and exposed to desiccating conditions darkness 8 C and 60 relative humidity for 0 2 5 8 and 12 days before planting in mini-rhizotrons. Water content and concentrations in soluble carbohydrates and starch were measured in buds stems and roots after treatment and before planting. These variables were related to root and shoot growth after planting. Fifty percent of the seedlings exposed for 12 days did not regenerate new roots and died. No mortality was observed for the shorter exposure durations. Seedlings exposed for 0 2 and 5 days displayed similar new root elongation values after planting which were three-fold higher than those observed in seedlings exposed for 8 or 12 days. Exposure also induced bud abortion and formation of epicormic shoots. These perturbations appeared to be related to the desiccation of the different plant components whereas non-structural carbohydrate concentrations were not affected during the exposure phase. dessication root growth shoot development soluble sugars starch Resume - Effets de 1 exposition à Fair sur le stress de transplantation chez le chêne rouge d Amerique. Des plants de chêne rouge Quercus rubra L âgés de 1 an à racines nues arrachés en mars ont été stockés en conditions ambiantes obscurité 8 C 60 d humidite relative pendant 0 2 5 8 et 12 j avant d etre plantés en minirhizotrons. La teneur en eau et les concentrations en sucres solubles et en amidon des differents organes ont été mesurées .