Summary: Secondary metabolites are involved in the plant stress response. Among these are scopolin and its active form scopoletin, which are coumarin derivatives associated with reactive oxygen species scavenging and pathogen defence. Here we show that scopolin accumulation can be induced in the root by osmotic stress and in the leaf by low‐temperature stress in Arabidopsis thaliana. A genetic screen for altered scopolin levels in A. thaliana revealed a mutant compromised in scopolin accumulation in response to stress; the lesion was present in a homologue of THO1 coding for a subunit of the THO/TREX complex. The THO/TREX complex contributes to RNA silencing, supposedly by trafficking precursors of small RNAs. Mutants defective in THO, AGO1, SDS3 and RDR6 were impaired with respect to scopolin accumulation in response to stress, suggesting a mechanism based on RNA silencing such as the trans‐acting small interfering RNA pathway, which requires THO/TREX function.

Published evidence indicates that nearly 60% of blueberry-producing countries experience yield instability. Yield is a complex trait determined by genetic and environmental factors. Here, using physiological and biochemical approaches, we tested the hypothesis that yield instability results from year-to-year environmental variation that limits carbon assimilation, storage and partitioning. The data indicate that fruit development depends primarily on the daily production of non-structural carbohydrates by leaves, and there is no accumulation of a starch buffer to allow continuous ripening under conditions limiting for photosynthesis. Photosynthesis was saturated at moderate light irradiance and this was mainly due to stomatal and biochemical limitations. In a dynamic light environment, photosynthesis was further limited by slow stomatal response to increasing light. Finally, labelling with ¹³CO₂ at specific stages of fruit development revealed a relatively even distribution of newly assimilated carbon between stems, roots and fruits, suggesting that the fruit is not a strong sink. We conclude that a significant component of yield variability results from limitations in photosynthetic efficiency that are compounded by an inability to accumulate starch reserves in blueberry storage tissues in a typical northern European environment. This work informs techniques for improving agronomic management and indicates key traits required for yield stability in such environments.

Producing food via vertical farming (VF) is an efficient method since it requires less space with increased yield per unit area. Such a system can assist in solving major food-shortage problems since it presents a higher crop yield per unit area compared to conventional farming. Thus, VF can be seen as a production method that can cope with the challenge of the constantly growing population, making it also possible to cultivate crops in regions with adverse climate conditions. However, the public might be concerned about the sustainability of VF systems since plants are produced in an unconventional setting. Therefore, there is a need to consider and evaluate the consumers’ acceptance of VF. The particular study attempts to both analyse consumer acceptance of VF in the Nordic areas and offer insights into VF acceptance among young customers in a comparative analysis. The results indicated that VF is not widely accepted by young Nordic consumers. The concept of sustainability is one of the principles driving forces behind consumer acceptance of vertical farms. The more cases of vertical farms in European cities, the better seems to be the level of acceptance among young customers and their willingness to purchase their products.