| 摘要: |
| 以西北农林科技大学校园内生民良好的耐旱树种刺槐（Roblnia pseudoacacia L.）、元宝枫（Acer truncatum Bge.）、沙棘（Hippophae rhanznoides L.）、白榆（Ulmus pumila L.）、油松（Pinus tabulaeformis Carr.）、白皮松（Pinus bungeana Zucc.ex Endl.）搜中生树种女贞（Ligustrum lucidum Ait.）和柳树（Salix matsudana Koidz.f.penduln Schneid）为研究对象，用压力套住2．5MPa下诱导1年生枝条发生木质部栓塞。研究自然条件下木质部栓塞的恢复特性，探讨木质部栓塞恢复特性与PV曲线水分参数间的天系。结果表明，木质部栓塞恢复的快慢，与其小枝的木质部栓塞脆弱性顺序基本一致；栓塞的发生和恢复与树木木质部的结构密切相关。植物木质部栓塞的发生、恢复，与植物耐旱性一样受多种因素控制，虽然与PV曲线水分参数有一定关系。但任何单一水分参数的排序。均与木质部栓寒的脆弱性和恢复速率不完全一致。术质部水势和树木小同部位间的水势梯度是影响木质部栓塞发生和恢复的最主要因素。蒸腾作用、气孔关闭及植物的渗透调节等可能也与木质部栓塞的恢复有关。 |
| 关键词: 木质部栓塞 栓塞恢复 PV曲线水分参数 |
| DOI： |
| 分类号:S718.43 |
| 基金项目:国家自然科学基金资助项目(30170766);教育部“优秀青年教师资助计划”项目 |
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| Refilling of embolism in the xylem of eight tree species and its relationship with Pressure-Volume parameters |
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AN Feng CAI Jing JIANG Zai-min ZHANG Yuan-ying LAN Guo-yu ZHANG Shuo-xin
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| Abstract: |
| Studied in this research were eight tree species,Robinia pseudoacacia L.,Acer truncatum Bge.,Hippophae rhamnoides L.,Ulmus pumila L.,Pinus tabulaeformis Carr.,Pinus bungeana Zucc.ex Endl.,Ligustrum lucidum Ait.,Salix matsudana Koidz.f.pendula Schneid.,growing well on Xi-lin campus of Northwest A&F Universityi.Xylem cavitations were induced by pressure collar under 2.5 MPa to observe the refilling of cavited xylem conduits in situ;pressure-volume curves of the eight trees species were also established to probe into relationships between embolism characteristics and water parameters.The results showed that:there was a good correlation between embolism refilling speed and its xylem vulnerability.This would suggest that both the occurrence and refilling of xylem embolism were related to xylem architectures.Like tree drought tolerant ability,xylem embolism was controlled by many factors,although there were some relationships between embolism and water parameters,all pressure-volume water parameters were not in accord with the occurrence and refilling sort of xylem embolism.Xylem water potential and water potential gradient in plant organs were main factors influencing the occurrence and refilling of embolism,but transpiration,stomatal closure and osmotic regulation may also play some roles. |
| Key words: xylem embolism refilling P-V parameters |
