Expression profiling of starch degradation-related genes (A) and starch biosynthesis-related genes (B) in the growing kernels after 24 h of dry wind treatment.

<p>Inset in A is an expansion of the figure showing the expression of four α-amylase-encoding genes. Black and white bars indicate dry wind and control treatments, respectively. Data are the mean ± SE (<i>n</i> = 3) of four inferior kernels pooled at the position in the panicles where the in situ Ψ_p assay was conducted. Significance at the 0.05 and 0.01 probability levels is indicated by * and **, respectively.</p

Percentage of filled kernels, final kernel weight, and rice appearance of tertiary pedicels attached at the middle primary rachis branches, where an in situ turgor assay was conducted, in a panicle grown under 24, 48, or 72 h dry wind treatment in growth chambers.

a<p>PR = perfect rice; MWR = milky white rice (ring-shaped chalky kernels); OR = other rice appearance.</p><p>Values in each treatment are means ± SE of four biological replications of panicles.</p><p>Means within a column followed by different letters are significantly different (<i>P</i><0.05) (Tukey’s Honestly Significant Difference [HSD] test).</p><p>Percentage of filled kernels, final kernel weight, and rice appearance of tertiary pedicels attached at the middle primary rachis branches, where an in situ turgor assay was conducted, in a panicle grown under 24, 48, or 72 h dry wind treatment in growth chambers.</p

Time course of changes in kernel growth score (A) visually observed through hull; definition of kernel growth scores, 0 through 1.0 (B); and changes in leaf water potential (LWP) (C), photosynthesis rate (D), and kernel weight (E) under 24 h dry wind conditions, starting at 13 days after heading (DAH).

<p>Open and closed circles indicate control and dry wind treatments, respectively. Gray area indicates the 24-h dry wind treatment. For A, each point is the mean ± SD of at least 20 kernels from 4 different plants; for C–E, each point is the mean ± SE of 3–6 samples from different plants.</p

Changes in panicle water potential (PWP) (A), stem water potential (SWP) (B), endosperm cell turgor (C), and the weight-averaged calculated endosperm osmotic potential (D) in developing rice kernels under dry wind conditions.

<p>Open and closed circles indicate control and dry wind treatments, respectively. In D, the inset indicates kernel water potential measured with an isopiestic psychrometer as a function of panicle water potential measured with a pressure chamber in both the control and dry wind treatments, collected at 13 days after heading (DAH) (open squares) and 14 DAH (closed squares). The gray zone indicates the duration of dry wind treatment, corresponding to 13 DAH. In the inset in panel D, the slanted dotted line labeled ‘1∶1’ indicates an equipotential line. The solid line indicates the regression line at 13 DAH. For A and B, each point is the mean ± SE of 3–19 samples from different plants. For C, data are means ± SE of 4–22 cells measured in 2–8 inferior grains in the same location on a panicle.</p

Time course of changes in ¹³C distribution in kernels located in the same position where an in situ turgor assay was conducted (A); in the panicle excluding the kernels (B); in the flag leaf (C); and in culms and leaf sheaths (determined as pooled organs with flag leaf sheath, uppermost internode, and other tissues) (D), corresponding to the sampled locations shown in the schematic potted plant to the right of the figure panels.

<p>‘M’ on <i>x</i>-axis indicates maturation. The plants were labeled with ¹³CO₂ for 20 min from the flag leaf at 13 DAH, just before the dry wind treatment was initiated, as indicated by the arrow. Open and closed circles indicate the control and dry wind treatments, respectively. Gray areas indicate the dry wind treatment. Each point is the mean ± SE of three samples from different plants. Significance at the 0.05, 0.001 and 0.0001 probability levels is indicated by *, **, and ***, respectively.</p

Isotopic ratio of ¹³C-labeled sodiated glucose, (<i>m/z</i> = 204 to <i>m/z</i> = 203) detected in the ethanol-insoluble fraction in kernels sampled at 24 h after the initiation of dry wind treatment.

<p>The plants were labeled with ¹³CO₂ at 12 days after heading (DAH) from the flag leaf to pre-fix ¹³C in the kernels prior to initiation of the dry wind treatment at 13 DAH.</p><p>Values indicate the mean ± SE of three biological replications of two pooled kernels.</p><p>Isotopic ratio of ¹³C-labeled sodiated glucose, (<i>m/z</i> = 204 to <i>m/z</i> = 203) detected in the ethanol-insoluble fraction in kernels sampled at 24 h after the initiation of dry wind treatment.</p

Transverse sections of a typical ring-shaped chalky kernel (A); and expanded SEM images taken at the three zones (B–D) shown in A.

<p>B, C, and D indicate the border between the inner translucent and chalky region (chalky cell in the left corner cell), the chalky region with loosely packed starch granules, and the translucent zone, respectively. The distance (<i>r</i>) from the endosperm center along the semi-minor axis in ring-shaped chalky kernels as a putative function of the duration of dry wind conditions (E). In E, the inner and outer borders of translucence and chalkiness correspond to the initiation of the dry wind treatment and the recovery point observed at 52 h in Fig. 2A, respectively; B, C, and D are indicated by arrows. ‘Epi’ indicates epidermis. In B–D, note that fissured fractures in each figure correspond to the cell wall. Bars in A and in B–D indicate 1 mm and 10 µm, respectively.</p

Development of Sheath-Flow Probe Electrospray Ionization Mass Spectrometry and Its Application to Real Time Pesticide Analysis

For the real time and direct analysis of chemical constituents from living beings and dry sample, sheath-flow probe electrospray ionization mass spectrometry (SF-PESI-MS) has been newly developed. The components from dry or semidry biological tissues can be extracted using the solvent and picked up by the needle for electrospray. This technique was applied to real-time pesticide analysis of living plants. The results have been validated with that of a well-known system, liquid extraction surface analysis mass spectrometry (LESA-MS). It is demonstrated that SF-PESI-MS can produce reasonable ionization efficiency, which is confirmed by LESA-MS

Schematic diagrams of possible turgor-induced nuclear gene expression.

<p>In a, RNA polymerase II binds to the promoter region, together with transcription factors, and the complex interacts with an activator attached to the enhancer to initiate gene expression. When Δ<i>P</i> is applied, it is speculated that Δ<i>P</i> might be perceived by both the promoter region of <i>GWD1</i> gene and the enhancer region, resulting in the promotion of multiple protein-DNA complexes binding (RNA polymerase II-transcription factors complex and the activating regulatory protein assembly) to increase gene expression (b). It is possible that these responses may occur reversibly in accordance with the changes in turgor pressure.</p

Yield and yield components of Hokuriku193 (H193) and Momiroman (MOMI) in 2012–2014.

<p>Sink capacity was calculated as single grain weight multiplied by the number of spikelets per area. Sink-filling rate was calculated as the hulled grain yield divided by sink capacity. Values for ripened grains and sink filling were transformed by using Box-Cox procedure prior to the analysis. ns indicates not significant by ANOVA.</p