以马铃薯 Y病毒 ( PVY)为毒源 ,以烟草 NC89为材料 ,采取光合指标和超微结构相结合的研究方法 ,对感染 PVY烟草的叶绿素含量、光合速率等生理指标以及叶绿体结构变化的规律进行了研究 .结果表明 :在光照、温度、湿度、CO2 浓度和土壤水分都相对恒定的条件下 ,烟草 NC89感染马铃薯 Y病毒 ( PVY)后 ,烟草的叶绿素含量、光合速率、气孔导度、蒸腾速率都出现了不同程度的降低 ,而细胞间CO2 浓度有所升高 ,Hill反应的活性却明显下降 ,叶绿体超微结构受到明显的破坏 . Taking PVY as a source of poison and tobacco NC89 as materials, the photosynthetic indexes and ultrastructure were used to study the changes of chlorophyll content, photosynthetic rate and chloroplast structure of PVY-infected tobacco plants The results showed that the chlorophyll content, photosynthetic rate, stomatal conductance and transpiration rate of tobacco after NC89 infection with PVY were significantly increased under the conditions of relatively constant light, temperature, humidity, CO2 concentration and soil moisture, All decreased to a certain extent, while the intercellular CO2 concentration increased, the activity of Hill reaction decreased obviously, and the ultrastructure of chloroplast was obviously destroyed.