苹果不同栽培方式叶幕及地面PAR变化规律研究

Study on Photosynthetically Active Radiation in Canopy and Ground of Apple Trees with Different Training Methods

测定了苹果主干型、开心型及小冠圆头型不同栽培方式下叶幕及地面光合有效辐射（ＰＡＲ）强度变化。结果表明，主干型与开心型苹果树平均叶幕及果际ＰＡＲ属高值组，比低值组圆头型树提高了１５３．５％～１７９．２％。高值组树形叶幕、果际地面辐射强度及树冠浅表层与内膛ＰＡＲ强度也显著高于圆头型苹果树。在晴天直射光及阴雨天散射光条件下，不同树形叶幕ＰＡＲ与地面ＰＡＲ辐射强度极显著正相关。

Photosynthetically active radiation (PAN) around canopy, fruits and from ground were determined in different training methods (central leader, opened central and round leader). The results indicated that, Comparing with round leader training, the mean value of PAN in central leader and without leader train- ing increased by 153. 5% - 179. 2%. Moreover, the PAN radiation intensity around canopy, fruits and from ground as well as inside and outside of crown were also higher. There were the significan relation- ship between PAN intensity around canopy and the PAR from orchard ground in fine or cloudy weather condition.