Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: "Mechanized to pollen harvesting with a view hybrid larch seed production. | Ann Sci For 1992 49 297-303 Elsevier INRA 297 Technical note Mechanized pollen harvesting with a view to hybrid larch seed production G Philippe p Baldet CEMAGREF Division Amelioration Génétique et Pépinières Forestieres Domaine des Barres 45290 Nogent-sur-Vernisson France Received 12 December 1990 accepted 2 March 1992 Summary The phenological lag that exists between flowering of European Larix decidua Mill and Japanese Larix leptolepis Gord larch clones present in French seed orchards is too great to allow hybrid seed production. Artificial pollination is thus required. This necessitates collection of large amounts of pollen from the Japanese larch grafts which are used as the male parent. To obtain sustained production at a reasonable price we attempted to collect pollen directly from the grafts mechanically. First pollen is forced to shed by whipping the tree enclosed in a tight-fitting tank fixed in front of a tractor. Then pollen is sucked backwards where it is filtered and collected. Despite certain restrictions connected with mechanical harvesting such as the impossibility to harvest in rainy weather and having to prune the trees so that they fit the size of the tank the results of the first 3 harvesting campaigns have proved very successful. When the atmospheric conditions are good the grafts are harvested 5 times each harvest requiring minutes. The seed orchard in which mechanical harvesting was tested includes 140 14-year-old grafts 3 metres high. These clones respectively provided 90 g 450 g and kg of dry pollen in 1988 1989 and 1990. So at least 2 years out of 3 the harvester enabled rapid collection of large quantities of pollen by only 1 or 2 workers in a conventional seed orchard. Moreover it seems obvious this technique would be particularly suited to indoor seed orchards. harvesting pollen I seed orchard genetic improvement Larix leptolepis larch Resume Récolte mécanisée de pollen de meleze en vue de I obtention de graine hybride. - .
