中文摘要：

为探明小粒咖啡适宜的水光管理模式,通过盆栽试验研究了3个亏缺灌溉水平：轻度亏缺灌水（DIL,（65%~75%）FC,FC为田间持水量）、中度亏缺灌水（DIM,（55%~65%）FC）和重度亏缺灌水（DIS,（45%~55%）FC）,3个遮阴水平：不遮阴（S0,自然光照）、轻度遮阴（SL,50%自然光照）和重度遮阴（SS,30%自然光照）对小粒咖啡日均光合特性、生长及水光利用效率的影响,并建立了不同亏缺灌溉和遮阴水平下水分和光能利用的回归模型。结果表明：与DIL处理相比,DIS处理降低小粒咖啡叶片净光合速率、气孔导度和光能利用效率分别为17.61%、22.99%和27.43%,减少总干物质积累量6.29%;而DIM处理对其影响不明显。S0处理的小粒咖啡叶片光能利用效率最小,SL处理次之,SS处理最大。S0处理或SS处理抑制叶片净光合速率和水分利用效率,SL处理增加干物质积累量11.14%。与DILS0处理相比,亏缺灌溉时遮阴显著降低叶片蒸腾速率而增加叶片光能利用效率。叶片光能利用效率与光合有效辐射呈显著的指数关系。随着亏水和遮阴程度的增加,灌溉水利用效率先增后减。小粒咖啡最优的水光耦合模式为轻度遮阴下轻度亏缺灌溉组合（DILSL）,该组合能同时获得较高的干物质累积和水分利用效率。

英文摘要：

Arabica coffee has the habit of shading cultivation and its growth often is inhibited by soil drought stress. Shade changes micro-climate of coffee growth and further affects photosynthetic characteristics and water consumption. The object was to explore suitable management mode of water and light,using three levels of deficit irrigation,i.e.,light deficit irrigation（ DIL,（ 65% ~ 75%） field capacity）,medium deficit irrigation（ DIM,（ 55% ~ 65%） field capacity） and severe deficit irrigation（ DIS,（ 45% ~ 55%） field capacity）,respectively,and three levels of shade,i.e.,no shade（ S0,natural light）,light shade（ SL,50% natural light） and severe shade（ SS,30% natural light）. The effect of deficit irrigation and shading levels on daily mean photosynthetic characteristics,growth and water-radiation use efficiency of arabica coffee was studied by pot experiments,and regression model was established under different deficit irrigation and shade levels. The results showed that compared with DIL,DISreduced coffee leaf net photosynthetic rate,stomatal conductance and radiation use efficiency by17. 61%,22. 99% and 27. 43%,respectively,and reduced the total dry mass by 6. 29%,but DIMhad no significant effects on leaf net photosynthetic rate,stomatal conductance,radiation use efficiency and total dry mass. Leaf radiation use efficiency of S0 was the lowest,SLwas the second and SSwas the highest. S0 or SSinhibited net leaf photosynthetic rate and water use efficiency,and SLincreased dry mass by 11. 14%. Compared with DILS0,shading under deficit irrigation reduced leaf transpiration rate but increased light use efficiency significantly. Leaf radiation use efficiency showed a significant exponential relation with photosynthetically active radiation. Irrigation water use efficiency was increased first and then decreased with the increase of water deficit level and shading degree. On the basis of high dry mass accumulation and water use efficiency,the suitable mode of water and light management of ara