Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: "Effects of buffer system pH and tissue storage on starch gel electrophoresis of allozymes in three tropical tree species. | Ann Sci For 1993 50 37-56 Elsevier INRA 37 Original article Effects of buffer system pH and tissue storage on starch gel electrophoresis of allozymes in three tropical tree species PD Khasa WM Cheliak 3 J Bousquet 1. 1 Centre de Recherche en Biologie Forestiere Faculte de Foresterie et de Géomatique Université Laval Sainte-Foy Quebec G1K 7P4 2 Departement de Biologie Faculte des Sciences BP 190 Université de Kinshasa Zaire 3 Forest Pest Management Institute Forestry Canada PO Box 490 1219 Queen street East Sault-Ste-Marie Ontario Canada P6A 5M7 Received 7 April 1992 accepted 31 August 1992 Summary The effects of 16 different electrophoresis buffer pHs 4 tissue storage conditions and 5 storage times on starch gel electrophoresis of 18 enzymes were determined to design a genetic variation sampling strategy for an isozyme study of 3 tropical tree species Racosperma auriculi-forme R mangium and Terminalia superba. The pH of the buffer systems had a significant effect on the number of putative gene loci and alleles resolved and the staining intensity of the 18 enzymes assayed. For Racosperma species 2 buffer systems B7 Tris-citrate gel pH lithium hydroxideborate electrode pH and H7 histidine-EDTA gel pH Tris-citrate electrode pH gave the highest average performance in resolving power. All buffer systems yielded poor results for Ter-minalia. Freezing of Racosperma embryos for up to 2 months did not seriously affect enzyme activity. However freezing cotyledon tissue of Terminalia decreased enzyme activity over a 2-month period. In general frozen tissues either with or without extraction buffer were consistently better than frozen tissues with extraction buffer and DMSO. Three classes of enzymes were defined based on their stability under the standardized storage conditions in vivo. Using the best buffer systems B7 and H7 and tissue storage conditions To or T-i 42 43 and 32 zones of activity were resolved for R auriculiforme R mangium and T superba .
