Biology subjects

Verdonk, J. C.

Publications and source records attributed to Verdonk, J. C..

3 recordsLinked to original sources

bioRxiv2025

Fragaria ananassa DAM4 expression correlates with vegetative growth during endodormancy breaking

Dormancy-Associated MADS-BOX (DAM)3 and DAM4 have been described as potential regulators of winter dormancy in cultivated strawberry (Fragaria x ananassa Duch.). These genes are upregulated under short day conditions and downregulated under chilling conditions. The aim of the current work is to test the hypothesis that the expression of DAM3 and DAM4 correlates negatively with vegetative growth during dormancy induction and breaking. The expression of DAM3 and DAM4 as well as plant morphology and physiology were analyzed during a period of semi-dormancy induction and breaking. Furthermore, DAM3 and DAM4 expression was compared between cultivars with different chill requirements. Lastly, the DAM1, DAM2, DAM3, and DAM4 expression of concurrently growing summer and winter leaves was compared at multiple stages of dormancy-breaking. DAM3 and DAM4 expression negatively correlated with leaf area and petiole length. We conclude that DAM3 and DAM4 expression patterns are consistent with that of regulators of semi-dormancy. DAM4 expression in particular correlates strongly with vegetative growth during semi-dormancy breaking. DAM3 or DAM4 expression were not found to correlate with the cultivar-specific chill requirements. Lastly, no relevant differences in DAM expression were found between summer and winter leaves.

plant biology↗

bioRxiv2025

Photoperiodic effects on early plant development in everbearing and seasonal flowering strawberry

In recent years, interest in vertical farming systems for strawberry cultivation has increased. Because of the increased costs associated with these systems, optimal use of resources, such as cultivation space and light, is a requirement. This necessitates a detailed understanding of plant development in different light conditions. The aim of this experiment was to analyze the effect of photoperiod on the early development of seasonal flowering and everbearing strawberry plants, and to compare the expression of genes known or suspected to be involved in the regulation of plant development between the two flowering types. Young, runner-propagated seasonal flowering and everbearing strawberry plants were grown under 10, 12, 14, or 16 h photoperiod in a climate-controlled vertical farm. Runners and flowers were removed throughout the experiment to limit their effects on assimilate balance. Morphological and physiological measurements were made weekly. Leaf material was collected for gene expression analysis. There were not many differences in plant growth and development between the short day conditions (10 and 12 h photoperiods), or long day conditions (14 and 16 h photoperiods). Short day conditions had a repressive effect on vegetative growth in all cultivars, but this effect was reduced in everbearing cultivars compared to seasonal flowering cultivars. No notable differences were found in gene expression between the two flowering types.

plant biology↗

bioRxiv2025

Blue Light Sonata: Dynamic variation of red:blue ratio during the photoperiod differentially affects leaf photosynthesis, pigments, and growth in lettuce

Vertical farming (VF) has unparalleled capacity to highly customize plant growth environments. In VF, red and blue LED lights are predominantly used as the two main wavelengths for photosynthesis. For many plants, red light increases biomass, and blue light can increase nutritional content. Because red light is more cost-and energy-efficient to produce than blue light, refined growth recipes are imperative to mutualistically improve efficiency with crop yield and quality. This studys aim was to balance lighting energy-use with growth and nutritional quality by using "dynamic lighting" recipes to reduce durations of high-intensity blue light. Lettuce (Lactuca sativa L.) was grown for 21 days at 220 mol m-2 s-1, receiving one of five R:B ratios (R:B100:0, R:B95:5, R:B89:11, R:B50:50, and R:B0:100) for either the whole 18-hour photoperiod (Whole Day), the first six hours of the photoperiod (Morning), or the last six hours of the photoperiod (Evening). Morning and Evening treatments received low blue (R:B89:11) for the remaining 12 hours of the day. The Morning and Evening high blue treatments had greater fresh weight and leaf area than their respective Whole Day treatments, attributed to reduced instantaneous leaf photosynthesis under high blue. High blue reduced photosynthesis during only the six hours of Morning and Evening treatments, compared to the full impact of static high blue for 18-hour Whole Day treatments. Intriguingly, with only six hours of R:B0:100, Morning and Evening treatments had the same high anthocyanin content as lettuce grown for 18 hours under R:B0:100. Therefore, daily blue light fraction can be reduced by using dynamic treatments to more efficiently promote growth and nutritional quality.

plant biology↗