摘要
以假俭草2个品系——Yaan和Common为试验材料,研究了中度干旱(土壤含水量为田间最大持水量的50%)和重度干旱(土壤含水量为田间最大持水量的35%)对光响应曲线的影响。结果表明,同一干旱水平下,在一定的光照范围内,净光合效率和气孔导度随着光强的增加而增大;随着干旱程度的加剧则发生显著降低,在Common品系中最大光合速率和光饱和点分别由22.3降到11.2μmol/(m2.s),578降到350μmol/(m2.s),在Yaan品系中则由24.5降到13.0μmol/(m2.s),694降到474μmol/(m2.s)。在同一光强下,Yaan的净光合速率、气孔导度值均大于Common。从光响应曲线来看,Yaan品系受到干旱的影响较小,对光强的利用能力高于Common。
We compared the light-response curves of two strains of Eremochloa ophiuroides,the Yaan and the Common strains from different origins,to determine if the two strains exhibit different tolerances to drought stress.Three watering regimes were designed：well-watered （80% of field water capacity,FWC）,moderate drought （50% FWC） and intense drought （35% FWC） all applied for one growing season.Net photosynthetic rate and stomatal conductance increased with increases of light intensity,while both significantly decreased when exposed to drought stress.The maximum assimilation rate （Amax） at saturation photosynthetic photon flux density （PPFD） and light saturation point （LSP） of Common were significantly reduced by drought.Amax decreased from 22.3 to 11.2 μmol/（m2·s） as the LSP dropped from 578 to 350 μmol/（m2·s）,while for Yaan,the Amax decreased from 24.5 to 13.0 μmol/（m2·s） as the LSP decreased from 694 to 474 μmol/（m2·s）.In addition,the net photosynthetic rate of the Yaan strain was much higher than that of the Common strain at the same light intensity.Based on the differences in light-response curves,it was concluded that the Yaan strain had stronger drought tolerance and a greater capacity to use light than Common,which was introduced from America.
出处
《草业学报》
CSCD
北大核心
2010年第3期251-254,共4页
Acta Prataculturae Sinica
基金
滇西北农牧区生计改良项目第二期(103642)
云南农业大学博士科研启动基金(A2002119)
云南农业大学动物科学技术学院基金(YNDKKY0710)资助
关键词
假俭草
净光合速率
气孔导度
光响应曲线
Eremochloa ophiuroides
net photosynthetic rate
stomatal conductance
light response curve
