Experiments for CB-839 mw leaf growth and carbohydrate analysis were started after 2 weeks

of cultivation under 50 μmol photons m−2 s−1; other experiments were started a week later, i.e., after 3 weeks of cultivation under 50 μmol photons m−2 s−1. Plants were watered daily or every other day throughout the cultivation and experiments. Light regimes In the first experiment, plants were exposed to different light regimes for 7 days without changing the other conditions in the climate chamber: constant daytime PAR of 50 μmol photons m−2 s−1 (C 50), “long sunflecks” (LSF, lasting 40 min) of 650 μmol photons m−2 s−1 once a day at around midday (LSF 650), “short sunflecks” (SSF, lasting 20 s) selleck chemicals llc of 650 μmol photons m−2 s−1 every 6 min during the daytime (SSF 650/6), and SSF of 1,250 μmol

photons m−2 s−1 every 12 (SSF 1250/12) or 6 min (SSF 1250/6) during the daytime. All sunfleck treatments were performed under the C 50 condition during the day. Additionally, some plants were transferred to constant daytime PAR of ca. 85 (C 85) or 120 (C 120) μmol photons m−2 s−1; the daily total PAR in these treatments was comparable with the values in the sunfleck treatments (ca. 3.6 mol photons m−2 day−1 in C 85, LSF 650, SSF 650/6 and SSF 1250/12; ca. 5.1 mol photons m−2 day−1 in C 120 and SSF 1250/6). The daily total PAR in C 50 was ca. 2.1 mol photons m−2 day−1. Light intensity was measured in a horizontal position at the height of the plants using a PAR meter (LI-250A; LI-COR, Lincoln, NE, USA). Constant illumination (C 50, C 85, and C 120) was provided by fluorescent lamps (Fluora L36 W/77;

Osram). Long sunflecks (LSF 650) were applied by placing plants under mercury-arc lamps (GW 84 463; GEWISS, Merenberg, Germany) installed in the same climate Edoxaban chamber. Treatments with short sunflecks (SSF 650/6, SSF 1250/12 and SSF 1250/6) were performed using Belinostat nmr halogen spotlight lamps (Haloline; Osram) aligned in a row. We note that these light sources had different spectral compositions, which could have had additional effects on plants. Under constant illumination (C 50, C 85 and C 120), leaf temperature was around 21~22 °C in the light, whereas it increased in the SSF conditions to reach 23~24 °C in the afternoon. The LSF raised the leaf temperature up to 27~28 °C during the 40-min treatment. A computer-assisted setup was built to control the duration and frequency of SSF. The halogen lamps were turned on shortly before each sunfleck event and moved over the plants in one direction (like a scanner); the velocity of the lamps’ movement was chosen such that each plant was exposed to the halogen spotlight for ca. 20 s. Upon reaching the end position, the lamps were turned off and brought back to the start position to wait until the next event.