tailieunhanh - Báo cáo lâm nghiệp: "Variations in seed and seedling responses to water stress in three provenances of Eucalyptus camaldulensis Dehnh"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài: Variations in seed and seedling responses to water stress in three provenances of Eucalyptus camaldulensis Dehnh. | 388s Ann. Sci. For. 1989 46 suppl. 388S-392S Forest Tree Physiology E. Dreyer ef al. eds. Elsevier INRA Variations in seed and seedling responses to water stress in three provenances of Eucalyptus camaldulen-sis Dehnh. A. Gibson and . Bachelard Department of Forestry Australian National University Canberra Australia Introduction Previous work Bachelard 1985 1986a b Gibson and Bachelard 1987 Yang et al. 1988 has shown that seeds and seedlings of eucalypt species subspecies and provenances within a species may differ in their germination and growth responses to water stress. Seeds from 3 provenances of Eucalyptus camaldulensis Dehnh. differed in their abilities to germinate under different atmospheric vapour pressure deficits VPD and plate matric potentials in a manner consistent with the moisture conditions in the environment in which these provenances occur naturally Gibson and Bachelard 1987 . In this study the effects of water stress on the initial establishment and early growth of seedlings from 3 provenances of E. camaldu-lensis were examined. Materials and Methods The 3 provenances of E. camaldulensis Katherine and Petford from monsoonal sites Tennant Creek from a semi-arid site were the same as those used previously Gibson and Bachelard 1987 . The initial establishment hypocotyl raised cotyledons opened of seedlings from germinated seeds placed on the surface of soils at different moisture contents 35 18 and 10 w w in containers in a controlled environment cabinet was observed and early seedling growth measured. Effects of water stress 10 . for 6 wk on tissue-water relations water use efficiency partitioning of dry matter into roots stems and leaves leaf growth and morphology were also determined in 8 wk old seedlings grown in pots in a glasshouse with and without added fertiliser. Results Establishment and early seedling growth Seedlings established from most seeds sown on the surface of soils at 35 . with slightly fewer Katherine seedlings .