Báo cáo khoa học: The effect of various seed pretreatments to improve germination in eight indigenous tree species in the forests of Cameroon

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: The effect of various seed pretreatments to improve germination in eight indigenous tree species in the forests of Cameroon...
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Báo cáo khoa học: "The effect of various seed pretreatments to improve germination in eight indigenous tree species in the forests of Cameroon" Original article The effect of various seed pretreatments to improve germination in eight indigenous tree species in the forests of Cameroon Pierre Marie Mapongmetsem Bahiru Duguma Bernard Aloys Nkongmeneck Eric Selegny a of Ngaoundere, Faculty of Science, PO Box 454, Ngaoundere, Cameroon University b / ICRAF Project, PO Box 2067, Yaounde, Cameroon IRAD c Eccles, Appartment n° Ogden, UI 84403, USA 3125 d of Yaounde I, Faculty of Science, PO Box 812, Yaounde, Cameroon University e University of Rouen, PO Box 76821, Saint-Agnan, France (Received 28 December 1998; accepted 12 April 1999)Abstract - Techniques were tested for improving germination in eight tree species indigenous to Cameroon forests. Manual scarifi-cation was the most efficient treatment for all species, although a significant interaction between treatment and species was found.Only one species was sensitive to all treatments. The use of sulphuric acid was not an effective alternative to manual scarification.© 1999 Inra/Éditions scientifiques et médicales Elsevier SAS.scarification / boiling water / sulphuric acid / sowing depthResumé - Effet de divers prétraitements sur l’amélioration de la germination de huit essences locales des forêts camerounaises.Des études ont été menées sur la germination de huit essences agroforestières indigènes des forêts camerounaises. La scarificationmanuelle était le meilleur traitement pour toutes les espèces, bien qu’il existait une interaction significative entre traitement et espèce.Une seule espèce a été sensible à tous les traitements. L’utilisation de l’acide sulfurique n’a pas été une alternative effective à la sca-rification manuelle. © 1999 Inra/Éditions scientifiques et médicales Elsevier SAS.scarification / bouillante / acide sulfurique / profondeur de semis eau traditional fallowing system is disintegrating. Fallow1. Introduction being shortened and cropping periods periods are This leads to declining soil fertility, falling lengthened. Rapid population growth and demands for increases yields and a serious problem of weed invasion into crop-in land production, especially from agriculture, have led land. These substantial constraints reveal the need toto a rapid disappearance of tropical rain forests and toland scarcity for peasant farmers [11]. As a result, the introduce a land use system which can allow the farm-* and reprints CorrespondenceFax: 25 25 20 25 14 15 or to save the forest while sustaining agricultural pro- pigs and small ruminants are the major domesticers sourceduction. Some agroforestry technologies (alley farming, of animal protein in the region [8].fodder banks, simple improved fallow, home gardens,live fences) have been developed with the objective toimprove soil fertility and reduce the fallow period 2.2. Selection of speciesthrough the use of nitrogen fixing trees and prunings [7].Most agroforesry trees used in the development of the An earlier ethnobotanical survey carried out in the areanovel technologies are exotic (Cajanus cajan, Sesbania [8] showed that local farmers had good knowledge ofsesban, Crotalaria anagyroides, Calliandra callothyrsus) indigenous agroforestry species, the ten most promisingand are not well known by the farmers. However, there being Ceiba pentandra (70 % interviews in which the =are several local varieties of agroforestry trees including species was mentioned), Terminalia superba (57 %),Alstonia boonei.De Wild., Ceiba pentandra (L.) Gearth., Triplochiton scleroxylon (56 %), Cordia platythyrsaCordia platythyrsa Bark., Milicia excelsa (Welw.) c.c (24 %), Milicia excelsa (24 %), Pycnanthus angolense ...