Our research philosophy is to look at interactions in addition to effects of single variables. We mainly work with whole plants, either indoors or in the field. We do manipulative experiments, both in the field and in controlled environments. When using controlled environments we use plants growing conditions as close as possible to natural conditions, except the factors under study. We also study the characteristics of the natural habitat of plants, to relate it to plant ‘behaviour’ in acclimation and adaptation. Our research is problem centred and most frequently spans different levels of organization and scientific disciplines. We are very careful about experimental design and statistics as a way of obtaining reliable data even in the outdoor environment that is subject to more random variation than a controlled environment. Sometimes we develop simulation models to study the coherence and implications of the results we obtain from our experiments, and to generate new testable hypotheses. In many cases, our experiments have been made possible by the novel instrumentation and software that we have developed for studying the different research questions.
Interactions in stomatal function: the modulation of the light sensitivity of stomata by other environmental factors. Physiological bases and ecological role.
How stomatal responsiveness is modulated by past growing conditions is a subject related to research that P. J. Aphalo did at the start of his career. Some of the hypotheses could not be then tested with the depth now possible. The photoreceptors involved in light sensing had not been characterized at the molecular level. Our most recent studies have looked at the changing role of different photoreceptors through the course of the day.
Light mediated plant-plant interactions: mechanisms, ecological implications and practical applications
P. J. Aphalo started doing research on this subject before arriving in Finland. This was the first research subject of the group and it has continued to be one of its focuses. Some of our papers on this subject have been seminal for later research of the role of information acquisition and use by plants through their sensory systems.
Perception and responses of plants to solar ultraviolet radiation by plants
We have been studying for about 25 years the effects of UVB and UVA radiation on the growth and secondary metabolism of woody and herbaceous plants. Initially we focused on direct effects and herbivory. Later we studied effects on leaf litter decomposition and soil fauna. We also did an assessment of the suitability of different action spectra for describing different responses measured outdoors in mature trees and tree seedlings. In the 1990’s our research focused on simulating ozone depletion and enhancing UV with lamps. Since 2001 we have been studying solar UV using filters to attenuate or it remove different regions of the daylight spectrum. Recently we have been studying the responses at the molecular level in sunlight and simulated sunlight, as well as using factorial experiments to characterize different interactions.
Development and validation of instruments and methods
We put considerable effort in the development of methods. Four aspects have been important: 1) development and testing of hardware for measurement of plant properties and behaviour, 2) development of hardware and software for measurement of environmental variables, and validation of quantification methods, 3) development of hardware and software for environmental control and visible and ultraviolet radiation treatments application, and 4) statistics, in relation to design of experiments and data analysis. We have published open-source software, including 13 R packages, edited and contributed to a handbook on research methods.