Solutions for sustainable agriculture often start from the perspective of industrial agriculture. However a large portion of the worlds food is produced by smallholders farmers who have a different perspective than large industrial growers/farmers. They work closer to nature, with restricted external inputs and limited access to knowledge, information and capital. Diversified, agroecological farming may be a good step to increase income in a way that is sustainable on the long run. Smallholder farmers need technical guidance to perform such a transition, but it is equally important to do this in a participatory way. Technical guidance should take a holistic approach: select resistant varieties, take preventive/hygiene measures, apply minimum tillage, find optimal plant spacing, mixed cropping, adjust plant nutrition, etc. And if any pests or diseases appear, apply biological control where feasible, and if needed use selective pesticides with minimal impact on the environment. The human approach needs work on knowledge, attitude and skills. In order to change the farmers’ behavior, one should understand the drivers (such as higher/more reliable production; lower input costs, matching market requirements, pests/diseases’ resistance against agrochemicals) that help farmers overcome barriers to change to whatever holistic approach (knowledge, availability of external inputs and credit, traditional practices, …). The big challenge is how to reach the millions of small holder farmers and enable them to partner with nature leading to better (quality) production and increased income. This panel will host people with hands-on experience in working on this challenge, with focus on the human component, but a strong foundation in proven possibilities of partnering with nature.

Monitoring the health and stress level of crop and energy plants is of fundamental importance for the optimization of growth and quality conditions in all areas of precision agriculture, energy crop production, as well as in advanced forestry. In greenhouse crop cultures all growth parameters should be monitored, optimized and controlled in order to achieve optimal results. Chlorophyll fluorescence in general is a very sensitive early reporter of various kinds of abiotic as well as biotic stresses on plants that adversely affect their optimal growth conditions. So far the JIP test, and - for remote sensing - various reflectance ratios are the most widely used methods to characterize photosynthetic status and stress conditions. This is because Chl fluorescence is a highly sensitive and specific reporter of almost all kinds of variations in the photosynthetic apparatus and the underlying stress factors. However, it is also clear that these so far widely used parameters are not fully sufficient to distinguish unequivocally between different types of stress and they also have substantial shortcomings in precisely defining the degree and severity of such stress factors. Thus the development of further advanced methods for non-invasive stress detection on crop plants growing under a variety of different conditions are in great need. The discussion panel is devoted to present and discuss new developments in the field of advanced non-invasive stress detection methods on plants in greenhouse cultures and precision agriculture. New detection methods as well as new signal analysis methods, including artificial intelligence and machine learning methods will be covered. Planned participants: Discussion Chair: Prof. dr. Roberta Croce, Head of Biophysics of Photosynthesis/Energy department at Vrije Universiteit Amsterdam, The Netherlands. Prof. Croce is a specialist in both the biochemistry as well as the biophysics of photosynthetic organisms, including plants as well as algae as energy producers. She is in particular specialized also on all kinds of optical spectroscopy and methods for plant stress characterization. Discussion panel members: - Prof. Dr. Alfred R. Holzwarth, Max-Planck-Institute für chemische Energiekonversion, Mülheim a.d. Ruhr, Germany. Prof. Holzwarth is a biophysicist with broad background in photosynthesis and the characterization of plant tissue employing all kinds of spectroscopic methods. Prof. Holzwarth is in particular specialized also on the development of novel non-invasive stress detection methods for plants as well as on the development of advanced data analysis methods. He will present both novel spectroscopy methods for stress detection as well as novel data analysis methods. - Dr. Jeremy Harbinson, University docent, Department of Agrotechnology and Food Sciences, Wageningen University, Wageningen, The Netherlands. Dr. Harbinson is specialist on Botany, Plant physiology, Optical spectroscopy and Biophysics, Adaptation physiology and Crop physiology. Dr. Harbinson will present novel developments in the improvement of crop yields using both physiological as well as spectroscopic methods. - Prof. Dr. Laurent Urban, University Professor University of Avignon and director of TERSYS network, France. TERSYS is a large research network comprising many laboratories in France directed towards the development and characterization of natural products from plants and the study of environmental effects on plants as well as on water management in agriculture. Advanced methods for characterization of stress factors are an important focus in that network.