金矮生苹果水分利用效率研究  

The Water Use Effeciency of the Goldspur Apple Tree

作　　者：王克勤[1] 王斌瑞[2] 王震洪[1] 

机构地区：[1]西南林学院,昆明650224 [2]北京林业大学,北京100083

出　　处：《生态学报》2002年第5期723-728,共6页Acta Ecologica Sinica

基　　金：国家"九五"科技攻关资助项目 ( 95 -0 0 7-0 1 -0 4 ) ;云南省自然科学基金资助项目 ( 1 999D0 0 1 3G)

摘　　要：通过对金矮生苹果 ( Malus pumila CV.goldspur)在不同土壤水分和光照条件下叶片光合速率 ( Pn)和蒸腾速率( Tr)进行测定 ,并计算水分利用效率 ( WUE)。结果表明 ,由于光合有效辐射 ( PAR)和土壤水分 ( SWC)决定了金矮生苹果Pn和 Tr,从而影响到 WUE。在水分胁迫存在时 ,不同 SWC条件下的 WUE随 PAR的变化规律相差较大 ,SWC为 1 0 %(田间持水量 F C的 5 0 % )左右时 ,WUE最大值在所有土壤水分处理中居于最高 ( 2 30 μmol CO2 /g H2 O)。在水分供应充足时 ,尽管 WUE在达到最大值之后下降缓慢 ,但最大值只有 1 6 0 μmol CO2 /g H2 O左右 ,并且各 SWC水平之间差异不显著 ,模拟曲线基本重叠。 WUE随 SWC的变化与光照条件有关 ,光强范围在 5 0 0 <PAR<1 0 0 0 μmol/( m2· s)时的 WUE最高。气孔阻力 ( RS)和叶水势 ( Ψl)分别为 2 .0 s/cm和 -3.0 MPa时 WUE最高 ,但这时 Pn较低 ,不利于林木的正常生长和结实。从 WUE、Pn和 Tr综合考虑 ,既能保证金矮生苹果有正常的光合作用 ,又有利于提高水分利用效率的 RS和 Ψl范围分别是 2～ 6 s/cm和 -2 .1～ -1 .6 5 MPa,它们所对应的土壤含水率范围是 1 1 %～ 1 5 % ,相当于田间持水量的 5 5 %～ 75 % ,这一范围可以作为金矮生苹果田间供水的理论指标。After measuring the photosynthetic rate and transpiration rate of the leaves of seven-year field and two-year potted Malus pumila CV. Goldspur under different soil water and illumination conditions, together with the calculation of water use efficiency (WUE), the result showed that because photosynthetically active radiation (PAR) and soil water content (SWC) affected the photosynthetic rate and transpiration rate of Goldspur, they thus influenced WUE. The response of WUE to different illumination conditions had some relation to the soil water. When water stress existed, under different SWC conditions, WUE would change greatly with PAR. When SWC was approximately 10% (50% of field capacity - FC), the maximum WUE was the highest among all the soil water treatment and reached about 230 μmolCO 2/gH 2O. When the water supply was adequate (SWC>15%), the maximum was only about 160 μmolCO 2/gH 2O. The differences among SWC levels were not obvious and the simulated curves almost overlapped although WUE decreased slowly after reaching the maximum. This showed that when severe water stress existed, because photoinhibition occurred earlier and severely influenced photosynthesis, it made the decrease rate of photosynthetic rate faster than that of transpiration rate. The phenomenon of rapid decrease of WUE occurred when PAR was not high and severely influenced the increase of WUE. With different SWC condition, WUE would change and this change was related to the illumination conditions. Under weak light (PAR<500 μmol/(m 2·s)), the maximum WUE was relatively low and after it reached the maximum, the decrease rate was comparatively high, together with the increase of SWC. Under strong light (PAR>1000 μmol/(m 2·s)), due to the photoinhibition, the maximum WUE was also relatively low, and the higher the light intensity was, the higher SWC was when the maximum occurred. WUE was the highest within the scope of 500<PAR<1000 μmol/(m 2·s). Although WUE reached the maximum when SWC was 8%～10%, trees were in severe wa

关 键 词：金矮生苹果 水分利用效率 光合有效辐射 土壤水分 

分 类 号：S661.1[农业科学—果树学] S152.75[农业科学—园艺学]