EARS miniPPM-100 Plant Photosynthesis Meter

The EARS miniPPM is the third generation of the Plant Photosynthesis Meter developed by EARS Plant Photosynthesis Monitoring B.V. (EARS-P2M), AgroCares’ sister company in Wageningen. It is a handheld, modulated saturation-pulse fluorometer: it uses the chlorophyll fluorescence signal of a leaf to measure how efficiently the plant is photosynthesising.

The instrument is simple to operate: press the button and a photosynthesis measurement is completed within a second. Laboratory tests show stable, reproducible measurements. Innovations in optics and electronics made the device much smaller and lighter than earlier versions without compromising on accuracy: it weighs 250 grams and does about 3,000 measurements on a full battery.

What the miniPPM-100 measures

Fluorescence in ambient light (F), maximum fluorescence (Fm) and photosynthesis yield (Y), at all light levels. Results are shown on the LCD display with various read-out options. The 100 is the entry model of the range; the 150, 200 and 300 add on-board storage, PAR measurement, photosynthesis rate and light-photosynthesis curves.

Application areas

The miniPPM is used in research, education and horticultural practice: herbicide efficacy and damage assessment, quality of plants, vegetables and fruit, seedling screening for breeding and monitoring of plant photosynthesis yield. Growers use it to see when light screening is needed: as a rule of thumb, screening is necessary when the photosynthesis yield drops below 40%.