【Abstract】 A new type of home-made computer-controlled non-modulated chlorophyll a fluorometer, the Plant Productivity Fluorometer PFM-101, is introduced including its main features, design and some applications. By using a latest highly integrated PIN-photodiode and FET linear amplifier in the PFM-101 the fluorescence kinetics curves and various fluorescence parameters can be measured and calculated automatically. It has superiority over the commercialized foreign ones in its versatile functions, super-low power consumption, high accuracy, low zero drift, low background noise and high stability etc. The errors produced in the measuring process are reduced to minimum by a unique data processing. Especially, the constant (Fo) and the inflection fluorescence (FI) can be determined with great precision and the inactive PS II reaction center can be calculated automatically. The instrument can be widely used in the field of agriculture, forestry, plant physiology and plant ecology, etc.更多还原