Soil culture experiments at two phosphorus levels were conducted to study the physiological responses(including chlorophyll content,MDA and soluble protein content,and APase activity in roots and leaves) of six Liriod...Soil culture experiments at two phosphorus levels were conducted to study the physiological responses(including chlorophyll content,MDA and soluble protein content,and APase activity in roots and leaves) of six Liriodendron chinese provenances with different phosphorus efficiency(PE). The result showed that low phosphorus stress would decelerate seedling growth and leaf development,lessen chlorophyll content and MDA content in leaves,and promote APase activity in root.There existed marked differences in physiological response among provenances with various PE under low phosphorus stress.It was found that the provenances with high PE possessed more and larger leaves,higher chlorophyll and soluble protein content than those provenances with low PE.Change of MDA content in leaves of provenances with high PE was small at two phosphorus levels,which meant the provenances with high PE were more resistive to environment stress.展开更多
以氮气为介质,采用160℃、180℃、200℃3种不同温度,2、4、6 h 3种不同时间分别对樟子松木材进行热处理改性,分析热处理前后樟子松材色、尺寸稳定性及力学性能的变化规律,并采用FTIR及XRD手段分析了其变化机理。结果表明,樟子松木材色...以氮气为介质,采用160℃、180℃、200℃3种不同温度,2、4、6 h 3种不同时间分别对樟子松木材进行热处理改性,分析热处理前后樟子松材色、尺寸稳定性及力学性能的变化规律,并采用FTIR及XRD手段分析了其变化机理。结果表明,樟子松木材色差随热处理温度和时间增大而增大,而明度随热处理温度和时间增大逐渐降低,处理材红绿色品指数a*值和黄蓝色品指数b*值均大于未处理材。樟子松木材平衡含水率随热处理温度和时间的增大逐渐减小,ASE和吸湿滞后现象随温度的增大逐渐增大。樟子松木材的顺纹抗压强度、抗弯弹性模量及抗弯强度随热处理强度的增加呈现先增大后降低的趋势,但在200℃下对这3个力学性能指标影响均不显著。热处理温度对樟子松材色及尺寸稳定性影响均极显著,热处理时间对樟子松木材明度、黄蓝色品指数b*、色差、平衡含水率和体积湿胀率影响均极显著。研究结果为高品质樟子松热处理木材的生产提供科学依据。展开更多
Soil culture experiment at two phosphorus levels was conducted to study the relationship between phosphorus environment and growth as well as dry mater accumulation of six classical Chinese tulip tree provenances from...Soil culture experiment at two phosphorus levels was conducted to study the relationship between phosphorus environment and growth as well as dry mater accumulation of six classical Chinese tulip tree provenances from various areas.The result showed that phosphorus supply would accelerate the growth and dry matter accumulation of Liriodendron chinese ,which would adapt to phosphorus starvation by increasing root-shoot-ratio and the relative value of root parameters.The western provenances were observed to grow better at two phosphorus levels than the eastern ones. The response model of phosphorus was varied with the provenances tested.It was found that Tongdao of Hunan and Wuyishan of Fujian were less sensitivity to phosphorus with high phosphorus efficiency and productivity,while Shaoyang of Hunan and Suichang of Zhejiang were more sensitivity to phosphorus with low phosphorus efficiency. Well-developed lateral root system and more fibrous roots under low phosphorus was perhaps one of the important reasons for the provenances with high phosphorus efficiency.It was preliminarily determined that Liping of Guizhou was an excellent provenance with moderate sensitivity to phosphorus, while Tongdao of Hunan was superior provenance with high tolerability to low phosphorus stress or high phosphorus efficiency.展开更多
文摘Soil culture experiments at two phosphorus levels were conducted to study the physiological responses(including chlorophyll content,MDA and soluble protein content,and APase activity in roots and leaves) of six Liriodendron chinese provenances with different phosphorus efficiency(PE). The result showed that low phosphorus stress would decelerate seedling growth and leaf development,lessen chlorophyll content and MDA content in leaves,and promote APase activity in root.There existed marked differences in physiological response among provenances with various PE under low phosphorus stress.It was found that the provenances with high PE possessed more and larger leaves,higher chlorophyll and soluble protein content than those provenances with low PE.Change of MDA content in leaves of provenances with high PE was small at two phosphorus levels,which meant the provenances with high PE were more resistive to environment stress.
文摘以氮气为介质,采用160℃、180℃、200℃3种不同温度,2、4、6 h 3种不同时间分别对樟子松木材进行热处理改性,分析热处理前后樟子松材色、尺寸稳定性及力学性能的变化规律,并采用FTIR及XRD手段分析了其变化机理。结果表明,樟子松木材色差随热处理温度和时间增大而增大,而明度随热处理温度和时间增大逐渐降低,处理材红绿色品指数a*值和黄蓝色品指数b*值均大于未处理材。樟子松木材平衡含水率随热处理温度和时间的增大逐渐减小,ASE和吸湿滞后现象随温度的增大逐渐增大。樟子松木材的顺纹抗压强度、抗弯弹性模量及抗弯强度随热处理强度的增加呈现先增大后降低的趋势,但在200℃下对这3个力学性能指标影响均不显著。热处理温度对樟子松材色及尺寸稳定性影响均极显著,热处理时间对樟子松木材明度、黄蓝色品指数b*、色差、平衡含水率和体积湿胀率影响均极显著。研究结果为高品质樟子松热处理木材的生产提供科学依据。
文摘Soil culture experiment at two phosphorus levels was conducted to study the relationship between phosphorus environment and growth as well as dry mater accumulation of six classical Chinese tulip tree provenances from various areas.The result showed that phosphorus supply would accelerate the growth and dry matter accumulation of Liriodendron chinese ,which would adapt to phosphorus starvation by increasing root-shoot-ratio and the relative value of root parameters.The western provenances were observed to grow better at two phosphorus levels than the eastern ones. The response model of phosphorus was varied with the provenances tested.It was found that Tongdao of Hunan and Wuyishan of Fujian were less sensitivity to phosphorus with high phosphorus efficiency and productivity,while Shaoyang of Hunan and Suichang of Zhejiang were more sensitivity to phosphorus with low phosphorus efficiency. Well-developed lateral root system and more fibrous roots under low phosphorus was perhaps one of the important reasons for the provenances with high phosphorus efficiency.It was preliminarily determined that Liping of Guizhou was an excellent provenance with moderate sensitivity to phosphorus, while Tongdao of Hunan was superior provenance with high tolerability to low phosphorus stress or high phosphorus efficiency.
