Current State. Future Prospects.

The Heinz Walz GmbH has been serving science for more than 40 years with sophisticated measuring devices for plant research. Further on, the course is set for innovations and developments. Technical progress in LED technology and other electronic components enables us to design instruments with unprecedented analytical potential. These novel devices again drive progress in science.

Vice versa, scientific issues reveal the demand for new instrumentation and, thus, stimulate analytical and technical progress. This kind of fruitful mutual stimulation is based on extensive exchange of information and ideas between researchers and instrument developers.

In this context, we are well prepared for the future by having employed several full-time plant scientists within the company. They are closely associated with a group of external scientists, who are mainly responsible for instrument development (Ulrich Schreiber, Jörg Kolbowski, Rolf Gademann and Christof Klughammer).

Being experienced in basic and applied plant research, these scientists are well aware of the needs of investigators and able to communicate with other scientists on special demands and applications.

The introduction of the first open gas exchange measuring systems in 1977 and the first PAM fluorometers in 1985, triggered a wave of research activities, with the range of new applications steadily growing until today. So far, PAM fluorometry has been used primarily for assessment of PS II activity. Now, the DUAL-PAM-100 system has spurred research on properties of PS I electron transport, thylakoid membrane energization and NADPH formation.

The successful combination of DUAL-PAM technology with gas analysis is expected to stimulate investigations on relationships between photosynthetic electron transport and CO2 fixation. Also, we look ahead to seeing how our new MULTI-COLOR-PAM will help to answer long-standing question on wavelength-dependent aspects of photosynthesis.

Another milestone, which is currently available as prototype, is the KLAS-100 Kinetic LED-Array Spectrophotometer. This very innovative device will allow the deconvolution of 9 different, simultaneously measured absorbance changes (Cyt f, Cyt b-559, Cyt b-563, C550, P515, light scattering peaking at 535 nm, zeaxanthin peaking at 506 nm, P700, plastocyanin) and, thus, may be expected to give new impulses for basic and applied photosynthesis research.

Specifically for investigations of PS I function, another prototype has been completed: the DUAL/KLAS-NIR Spectrophotometer. The device measures chlorophyll fluorescence and fast absorbance changes in the NIR. The absorption measurements permit detailed analysis at high time resolution of the redox states of the PS I reaction center (P700), its electron donor, plastocyanin, and its electron acceptor, ferredoxin. Certainly, the new device will provide novel insights into the reaction dynamic of PS I and its interaction with PS II photochemistry.