FMS 2 is a portable system for measuring modulated fluorescence. The whole system is integrated and extremely easy to use. Easily removable batteries let the use of this system for an all day of measurement. A multiple battery charger can recharge up to four batteries simultaneously.

Features

FMS 2 is a portable system for measuring the fluorescence with the technique of modulated pulses, and then can be used both to measure samples that are on the ambient light or in conjunction with other techniques such as analysis of gas exchange with IRGA.

The heart of the system is represented by the control unit which has limited dimensions (18 x 10 x 10 cm) and it is extremely lightweight (2.0 kg), in order to used for a whole day of measurement. The control unit contains all the necessary light sources and electronics controls to compensate for temperature variations. Light sources are:

• 594 nm modulated
• 470 nm blue LED (optional)
• Halogen actinic lamp / saturating
• 735 nm far-red LEDs for preferential excitation of PSI

The system is powered by 12 V batteries of 2.0 Ah, which can produce a one hour of full actinic light or about 800 saturating pulses. With the multi-charger can be charged up to 4 batteries simultaneously. The batteries are easily replaceable in the field.

The instrument is provided with an optical fibre that can transmit and receive signals from the instrument to the sample, that is supported by a leaf clip. There are two types of leaf clip:

• Clip PAR / Temperature. The clip has integrated a PAR sensor and a leaf thermocouple. Simultaneous measurements of fluorescence parameters, PAR and temperature are started by a button on the clip. PAR sensor can be used in two positions allowing the calibration of the light output from the FMS 2 towards the sample.
• Clips to adapt sample to the dark. Many leaves can be light adjusted simultaneously by these clips with blinds sliding window.

Check

The system is controlled either by a software in Windows ® on a PC connected via serial cable or directly working on the keyboard of the instrument.

Control PC

Modfluor32 software allows manual control of all light sources and measuring tasks using a graphical interface. The recorded data are displayed with a recorder emulator, and measured parameters and derived are numerically displayed in a separate window.

FMS 2 can be used in conjunction with other techniques for studying photosynthesis. Optional adapters are available to interface the fluorimeter with all line Hansatech oxygen electrodes to allow simultaneous measurements of oxygen evolution and fluorescence. FMS2 is also compatible with systems for measuring infrared gas exchange (Irga) and in particular it has created a dedicated interface for the analyzer PPSystems CIRAS.

Parameters measured

• Fo - fluorescence level when sample dark-adapted and Qa fully oxidised
• Fm - maximum fluorescence yield
• Fv - variable fluorescence level (Fm - Fo)
• Fv/Fm - maximum quantum efficiency of PS2
• Fs - steady state light-adapted fluorescence signal
• Fm' - signal when Qa fully-reduced during photosynthesis
• Fo' - signal when Qa fully-oxidised with far-red light during photosynthesis
• Fv'/Fm' - antennae efficiency of PS2
• PSII - quantum efficiency of PS2
• qP - photochemical quenching coefficient
• qNP - non-photochemical quenching coefficient
• NPQ - alternative expression of the extent of non-photochemical quenching
• ETR - estimate of the electron transport rate when used with PAR / Temp leaf-clip 

Datasheet