E xisting photosynthetic rate m easurem ent system can not be applied to the m ulti-point and rem otely real-tim e m onitoring. T o solve such a problem , a rem ote crop photosynthetic rate m easurem ent system based on Z igB ee is proposed in this study. T he system consists of tw o parts, and they are the data acquisition nodes and the data receiving nodes. D ata acquisition nodes pass data to the data receiving nodes by a Z igB ee netw ork, and then the data receiving nodescompletethedataprocessinganddisplaying.TheZigBeeprotocolischosentonetworkthedifferentnodesinour m easurem entsystem to achieve the rem ote data m onitoring.The experim entsofcalibrating and validating the sensorsare carried out,and the m easurem entdata ofthe sensorsare proved accurate.There existsslightm easurem enterrorsbetw een our system and L I-6400. T he average errors of carbon dioxide concentration, tem perature and hum idity are-1.09% ,-7. 68% and 0.64%,respectively.T he errors are in the perm itted range,indicating thatthe sensors perform w ellin m easuring m ajor param eters of crop photosynthetic rate. It is show ed that our m easurem ent system can apply to those situations wherephotosyntheticrateislessthan5μmol/(s·m2).Anapproximatelylinearrelationshipexistsbetweenthemeasurements ofthesystem andLI-6400 (y=0.8783x+0.3164),whichindicatesthatthepatternsofvariationsofthetwomeasurement system sare com parable.Therefore,the system m eetsthe need form easuring the crop photosynthetic rate.Furtherm ore, the current system has a num ber of advantages, such as low pow er consum ption, low running cost, and flexible node expansion.%现有成熟光合速率测量系统，不能多点采样及远程实时监控。针对该不足，提出了一种基于ZigBee技术的作物光合速率远程测量系统。该系统主要由数据采集节点和接收节点两部分构成，数据采集节点通过ZigBee网络将数据传给接收节点，在数据接收端完成数据的处理和显示，选用ZigBee协议对本测量系统的节点进行组网编程，实现数据远程监测。进行传感器测量值准确性验证实验，得出本系统二氧化碳浓度、温度和湿度测量值与LI-6400平均测量偏差依次为-1.09%、-7.68%和0.64%，均在误差允许范围内，表明传感器能有效测量光合速率重要参数。进行光合速率测量实验，数据显示本系统适合光合速率低于5μmol/(s·m2)的应用场合，且与LI-6400测量值存在近似线性关系（y=0.87827x+0.31641），说明测量值变化规律一致，满足光合速率测量要求。同时本系统具有低功耗，低成本，节点扩展灵活等优点，方便扩展应用。
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