tailieunhanh - Báo cáo khoa học: "Polyphenolic and enzymatic characterization of ageing and rejuvenation of hybrid walnut trees (Juglans nigra x Juglans regia): relationship to growth"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: "Polyphenolic and enzymatic characterization of ageing and rejuvenation of hybrid walnut trees (Juglans nigra x Juglans regia): relationship to growth. | 190s Ann. Sci. For. 1989 46 suppl. 19ŨS-193S Forest Tree Physiology E. Dreyer et al. eds. Elsevier INRA Polyphenolic and enzymatic characterization of ageing and rejuvenation of hybrid walnut trees Juglans nigra X Juglans regia relationship to growth c. Jay-Allemand1 A. Drouet2 A. Ouaras2 and D. Cornu1 1 Station d Amelioration des Arbres Forestiers INRA Ardon 45160 Olivet and 2 Laboratoire de Physiologie du Vieillissement et de la Senescence des Végétaux Supérieurs Uni-versité d Orleans BP 6749 45067 Orleans Cede 02 France Introduction This paper is mainly devoted to the polyphenolic and enzymatic characterization of hybrid walnut rejuvenation in order to find better plant materials treatments and conditions which are propitious to propagation. Consequently a comparative study of adult and rejuvenated annual shoots was undertaken. Rejuvenation widely linked to vegetative propagation was described by Bonga 1982 and it has been shown on hybrid walnut that the propagation success by in vitro culture of cuttings was strongly dependent upon severe annual coppicing Cornu 1977 . First results with phenolic compounds and enzymes were obtained during the annual growth of walnut 1 juvenility and rejuvenation seemed to be linked to high values of the ratio of typical polyphenols during the first stages of growth after bud burst Jay-Allemand et al. 1987 1988 2 enzyme activity changes were found between adult and rejuvenated shoots while no difference was noted in the total protein content Drouet etal. 1989 . Key results and a brief discussion on different factors involved in walnut ageing and rejuvenation will be presented. Materials and Methods Two clones of hybrid walnut Juglans nigra X J. regia which were grown in a nursery in Orleans were used. Each clone was represented by 2 different physiological situations 1 a rejuvenated 13 yr old tree obtained by annual coppicing in March for 10 yr each stump producing at least 60 sprouts 2 10 yr old adult form obtained from a .