Laboratory and field studies on aphid damage in wheat are described. Both direct and indirect effects of aphids on the behaviour of the crop were studied. In the laboratory a clear effect of honeydew and yeasts on photosynthesis was found. This effect could not be demonstrated under field conditions, since even at yield loss levels of 700 kg ha -1 the size of this effect may be undetectable with crop enclosures reaching an accuracy of 10o/o. The effect of honeydew on ageing, measured in the laboratory trials was also found in the field and may form a major cause of the yield losses found in the field. Yield losses under field conditions reached 700 kg ha -1 and were for 72o/o due to direct sucking damage of the 35 aphids, found maximally per culm, and direct and indirect honeydew effects. Saprophytic and possibly also some necrotrophic fungi caused 28% of the yield losses. The exact contribution of each of the damage factors was not revealed but it was demonstrated that direct and indirect effects contribute to the final yield losses.

Physical inactivity and exercise training result in opposite adaptations of vascular structure, but the molecular mechanisms behind these adaptations are not completely understood. Therefore, this study examined both vascular characteristics of the superficial femoral artery (using ultrasound) and gene expression levels (from a muscle biopsy). First, we compared able‐bodied controls (n=6) with spinal cord‐injured (SCI) individuals (n=8) to assess the effects of long‐term deconditioning. Able‐bodied controls were also examined before and after short‐term deconditioning using 3 weeks of unilateral limb suspension (ULLS). SCI individuals received 6 weeks functional electrical stimulation (FES) exercise training. Baseline diameter and hyperaemic flow were lower after deconditioning and improved after training, whilst intima‐media thickness/lumen ratio was higher after deconditioning and decreased by training. Gene clusters including the vascular endothelial growth factor (VEGF) pathway (Figure), transforming growth factor beta 1 (TGFB1), and extracellular matrix (ECM) components strongly related with these vascular adaptations. Thus, this approach resulted in the identification of genes that may be involved in structural vascular adaptations after physical (in)activity.GL was funded by Gelderland‐Overijssel‐EFRO, NTLvD by the Netherlands Heart Foundation, and JGH by the EURYI award.

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