tailieunhanh - Báo cáo lâm nghiệp: "Influence of the moisture content of forest tree its response to different viability tests pollen on"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài: Influence of the moisture content of forest tree its response to different viability tests pollen on. | 60s Ann. Sci. For. 1989 46 suppl. 60s-63s Forest Tree Physiology E. Dreyer et al. eds. Elsevier INRA Influence of the moisture content of forest tree pollen on its response to different viability tests J. Webber1 and M. Bonnet-Masimbert2 1 Research Branch British Columbia Ministry of Forests Victoria Canada and 2INRA Station dAmélioration des Arbres Forestiers Ardon 45160 Olivet France Introduction Pollen management has become an integral part of intensive tree improvement especially for facilitating breeding programs and improving both orchard yields and genetic efficiency. To handle pollen successfully particularly its storage drying to moisture contents of less than 10 is required Webber 1987 and unpublished data . However in certain angiosperms dehydration can have a detrimental effect on pollen germination and vigor which is only restored by rehydration Shivanna and Heslop-Harrison 1981 . The cause of this reduction in germination and viability with dehydration is not fully understood but loss of membrane integrity may be involved Shivanna and Heslop-Harrison 1981 . Certainly it is a principal factor in the loss of vigor in corn Kerhoas eta . 1987 . In this paper data from previous experiments are summarized to show the factors affecting reactivation of pollen vigor and data from recent tests which demonstrate the effect of rehydration atmosphere humidity temperature and exposure time on in vitro viability response are shown. Materials and Methods Procedures for testing in vitro viability have been described by Charpentier and Bonnet-Masimbert 1983 and Webber 1987 . The effect of 2 relative humidities 70 and 100 RH and 3 temperatures 10 20 and 30 C on rehydration of Douglas fir Pseudotsuga men-ziesii pollen and their effects on germination and conductivity over 9 exposure times 0 3 6 16 24 48 72 96 and 120 h were tested. The 70 RH was generated by controlling wet-bulb dry-bulb temperatures using a water bath T1 and an incubator T2 . The 100 RH was created by .