Báo cáo lâm nghiệp: Comparison of nitrogenase and nitrate reductase activities in two nitrogen-fixing tree species: black alder (Alnus glutinosa) and black locust (Robinia pseudoacacia)

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài: Comparison of nitrogenase and nitrate reductase activities in two nitrogen-fixing tree species: black alder (Alnus glutinosa) and black locust (Robinia pseudoacacia)...
Nội dung trích xuất từ tài liệu:
Báo cáo lâm nghiệp: "Comparison of nitrogenase and nitrate reductase activities in two nitrogen-fixing tree species: black alder (Alnus glutinosa) and black locust (Robinia pseudoacacia)"Comparison of nitrogenase and nitrate reductaseactivities in two nitrogen-fixing tree species:black alder (Alnus glutinosa)and black locust (Robinia pseudoacacia) 1 BoutekrabtG. Pizelle S. Benamar F. 1 1 G. 2 ThiéryI Laboratoire de Physiologie Végétale et Forestibre, Facult6 c/es Sciences, BP 239, 54506Vandœuvre-Iès-Nancy Cedex, and2 Physiologie V6g6tale, ENSAIA, 54500 !anda°wre-/e5-/B/ancy. FranceIntroduction desire to progress urst, 1983); hence, our understanding of its physiology. in In an extension of our work on nitrogen nutrition of A. glutinosa (e.g., Pizelle and the symbiotic nitrogen-fixingAmong trees Thiéry, 1986), the present paper examinesof the temperate zone, black alder (Alnus and nitrate reductase the nitrogenaseglutinosa, L. Gaertn.) and black locust ac- tivities, measured in vivo, in R. pseudoa-(Robinia pseudoacacia L.) can be re- cacia and compares them with the datagarded as typical actinorhizal (frankial) from A. glutino!;a.and leguminous (rhizobial) woody species,respectively. Important differences be-tween both species concern their biologi-cal, ecological and symbiotic characteris- Materials and IMethodstics, and the greater amount of workrecently devoted to A. glutinosa, whichlikely prevails over R. pseudoacacia on Plant material was harvested in the early afternoon from 1 yr old black alders natu- 3-20 !the following grounds: ubiquity in Europe, rally growing on sandy alluvium and from blackbetter sylvicultural qualities, absence of locusts planted for about 10 yr on a sandy andspines and suckers, easier collection of stony bank; both sites were located on a sili-the nitrogen-fixing organs, attraction to the ceous substrate in the Moselle valley near recently recognized actinorhizal Nancy.moresymbiosis (Tjepkema et al., 1986). Never- Nitrogenase (t’BI2ase) activity was assayed by the C reduction method on excised actino- H 2theless, R. pseudoacacia is also a tree of rhizal lobes of alder and on excised nodules ofinterest both for its role as symbiont in black locust. Nitrate reductase (NR) activitiesnitrogen fixation and for its potential value were assayed on 5 mm sections of small rootsas timber and wood fiber source (Moiroud (diameter11 mrr!; 100 mg fresh tissue) and onand Capellano, 1982; Turvey and Smeth- disks of young fully expanded leaves (diameter: disks). The root samples were autumn than in R. pseudoacacia. During12 mm; 2 infiltrated in 2.5 ml of 0.1 M NaK phos-vacuum the growing season, N activity of the ase 2phate buffer, pH 7.5, with or without 0.05 M nodules of R. pseudoacacia reachedKN0 After incubation for 1 h at 30°C in the.3 higher values than that of the actinorhizasdark, 1.5 ml of incubation medium were cleared ...