A novel sesquiterpenoid was isolated from the whole plant of Glechoma longituba. Its structure was elucidated as 1, 8-epoxy-7（11）-germacren-5-one-12, 8-olide 1 on the basis of spectral evidences.
Aims Most plants are clonal in nature.Clonal ramets can share water,nutrients and photosynthate,especially when they experience patchy resources.Patch contrast(i.e.a difference in resources among patches)and patch dir...Aims Most plants are clonal in nature.Clonal ramets can share water,nutrients and photosynthate,especially when they experience patchy resources.Patch contrast(i.e.a difference in resources among patches)and patch direction(i.e.source–sink relations)are among the basic attributes of spatial patchiness.Here,I hypothesize that young established ramets in nutrient-rich patches support old ramets in nutrient-poor patches when ramets are subjected to different patch contrasts and patch directions.Methods In a greenhouse experiment,old and young ramets of Glechoma longituba were grown in four combinations consisting of patch contrast and patch direction.Minus patch direction refers to a patch combination in which parent ramets grow in nutrient-rich patches while connected daughter ramets grow in nutrient-poor ones and plus patch direction is the opposite direction.Imeasured photosynthesis and fluorescence traits,harvested all ramets,took morphological measures,weighed their dry mass and determined their nutrient uptake and use.Important Findings For parental ramets of G.longituba,patch contrast and patch direction and their interactions had no significant effects on net photosynthetic rate,maximal fluorescence yield,photochemical quenching(quenching refers to any process which decreases the fluorescence intensity of a given substance),non-photochemical quenching,nutrient uptake,biomass and stolon weight ratio.Patch direction alone significantly affected root weight ratio.Large patch contrast enhanced N use efficiency(NUE)and P use efficiency(PUE);plus patch direction decreased NUE,but increased PUE;the patch contrast by patch direction interaction affected PUE and K use efficiency(KUE).There were significant interactions between patch direction and patch contrast on PUE and KUE.It is concluded that soil nutrient patchiness may influence nutrient use strategies,but not nutrient uptake,photosynthesis and growth of parent ramets of G.longituba connected to daughter ramets,and that patch contrast and patch direction jointly affect PUE and KUE.展开更多
基金the National Natural Science Foundation of China [No. 30460150] the Previous Special Research Program of Significant Foundation Research 2004CCA03800.
文摘A novel sesquiterpenoid was isolated from the whole plant of Glechoma longituba. Its structure was elucidated as 1, 8-epoxy-7（11）-germacren-5-one-12, 8-olide 1 on the basis of spectral evidences.
基金National Natural Science Foundation of China(40435014).
文摘Aims Most plants are clonal in nature.Clonal ramets can share water,nutrients and photosynthate,especially when they experience patchy resources.Patch contrast(i.e.a difference in resources among patches)and patch direction(i.e.source–sink relations)are among the basic attributes of spatial patchiness.Here,I hypothesize that young established ramets in nutrient-rich patches support old ramets in nutrient-poor patches when ramets are subjected to different patch contrasts and patch directions.Methods In a greenhouse experiment,old and young ramets of Glechoma longituba were grown in four combinations consisting of patch contrast and patch direction.Minus patch direction refers to a patch combination in which parent ramets grow in nutrient-rich patches while connected daughter ramets grow in nutrient-poor ones and plus patch direction is the opposite direction.Imeasured photosynthesis and fluorescence traits,harvested all ramets,took morphological measures,weighed their dry mass and determined their nutrient uptake and use.Important Findings For parental ramets of G.longituba,patch contrast and patch direction and their interactions had no significant effects on net photosynthetic rate,maximal fluorescence yield,photochemical quenching(quenching refers to any process which decreases the fluorescence intensity of a given substance),non-photochemical quenching,nutrient uptake,biomass and stolon weight ratio.Patch direction alone significantly affected root weight ratio.Large patch contrast enhanced N use efficiency(NUE)and P use efficiency(PUE);plus patch direction decreased NUE,but increased PUE;the patch contrast by patch direction interaction affected PUE and K use efficiency(KUE).There were significant interactions between patch direction and patch contrast on PUE and KUE.It is concluded that soil nutrient patchiness may influence nutrient use strategies,but not nutrient uptake,photosynthesis and growth of parent ramets of G.longituba connected to daughter ramets,and that patch contrast and patch direction jointly affect PUE and KUE.
基金This work was supported by the National Natural ScienceFoundation of China(30460150)the Previous Special Research ProgramofSignificant Fundation Research(2004CCA03800)
基金Foundation item： This work wss supported by the National Natural Science Foundation of China [30460150] and the Previous Special Research Program of Significant Foundation Research 2004CCA03800
