Abstract: In order to explore the effects of natural grass on apple orchard microclimate,this study took the apple orchard with clean tillage and artificial-planted grass as control,the microclimate,fruit sunburn and leaf early deciduous disease of apple orchard with natural grass were continuously monitored in Weibei dry plateau. The results showed that the air relative humidity of natural grass and artificial-planted grass between rows increased by 11.77% and 10.53%,respectively,and inside the canopy increased by 12.01% and 11.16%,respectively. Natural grass and artificial-planted grass reduced the air temperature between the rows and inside the canopy,and reduced the soil temperature. The illumination intensity between rows of natural grass and artificial-planted grass decreased by 5.59% and 5.05%,respectively,and the canopy reflection spectra,tip sharpness and fruit sunburn rate were decreased,but the damage degree of leaf early deciduous disease was increased. The effects of natural grass on microclimate,fruit sunburn rate and leaf early deciduous disease of apple orchard were basically the same as that of artificial-planted grass. Pruning,prevention and control of diseases and pests should be strengthened in orchards to eliminate the adverse effects of natural grass and artificial-planted grass on the fruit tree growth.

Key words: Apple orchard, Natural grass, Artificial-planted grass, Microclimate, Fruit sunburn rate

摘要： 为了探寻自然生草对果园小气候的影响，试验以苹果园清耕和人工生草为对照，监测了自然生草对渭北旱塬苹果园小气候、果实灼伤和早期落叶病的影响。结果表明：自然生草与人工生草果树行间的空气相对湿度较清耕分别提高了11.77%和10.53%，树冠内的分别提高了12.01%和11.16%。自然生草和人工生草降低了果树行间及树冠内的空气温度及果园土壤温度。自然生草和人工生草果树行间的光照强度较清耕分别降低了5.59%和5.05%，且降低了树冠反射光谱、新梢尖削度和果实日灼率，但却提高了早期落叶病的危害程度。自然生草对苹果园小气候、果实灼伤及早期落叶病的影响与人工生草的基本一致。综上所述，自然生草和人工生草的果园应加强修剪及病虫防治，以消除自然生草和人工生草对果树生长带来的不利影响。

关键词: 苹果园, 自然生草, 人工生草, 小气候, 日灼率