Fig 1.
Characterization of Brachypodium growth pattern under two different conditions.
(A) Brachypodium grown under more commonly used growth chamber conditions (20-hour light, 24°C; 4-hour dark, 18°C; 150 μE). (B,C) Brachypodium grown under stem-elongating conditions (16-hour light, 20°C; 8-hour dark, 21°C; 220 μE).
Fig 2.
Characterization of Brachypodium growth pattern under stem-elongating conditions.
(A) Number of tillers and length of main stem as a function of plant age. Measurements were performed on three independent batches of plants with similar results whereof one is shown. Standard deviation is shown (n = 16). (B) Diagram showing all stems of a single plant and location of four internodes sampled along the stem, S-01 to S-04. Senescent leaves were removed. The senescent leaves for the main stem are placed at the left.
Table 1.
Biomass accumulation in aerial vegetative organs of 12-week-old plants.
Fig 3.
Carbon storage in the Brachypodium stem.
(A) Quantification of starch and sucrose levels in leaf, middle part of stem, and bottom part of stem, with and without dark-treatment. (B-G) Iodine staining of Brachypodium stem cross-sections. Progressive stem stages from bottom towards the top of the stem are shown (B, S-04; C, S-03; D, S-02; E and F, S-01). E is from within while F is from above the leaf sheath. More starch is accumulated in the cortex parenchyma in F compared to E (arrow) while the starch levels in the pith parenchyma appear equal in the two samples. G shows iodine staining of starch granules in parenchyma cells in the vascular bundle (arrows).
Fig 4.
Plastid development in the Brachypodium stem.
(A) Decrease of stem chlorophyll in stem from 9- to 12-week-old plants. (B) Chloroplast auto-fluorescence by confocal laser scanning microscopy. Cross-section is equivalent to section in Fig 3F (S-01 internode, above leaf sheath, 12-week-old plant). (C) Merged image of auto-fluorescence in (B) with the bright field channel showing that the strong auto-fluorescence originates from cortex parenchyma cells. (D) TEM analysis of thylakoid membrane stacks in internodes of plants of different age and at different locations within the stem cross-section.
Table 2.
Expression of starch related genes in stem and leaf.