Hypocotyl elongation in Chrysanthemum paludosum ‘North Pole’ at three different day/night temperature combinations (15/25°C, 20/20°C, 25/15°C) were measured and analyzed using an image processing technique. Experiments were conducted in growth chambers where photosynthetic photon flux (PPF) of 150μmol m^-2 s^-1 on the canopy level with a 12h photoperiod was provided by fluorescent lamps. Images of ten plants were acquired and stored every 10 minutes for 5 days. The stored images were analyzed using a software developed in-house applying a subpixel estimation with an area-based pattern-matching algorithm. It was clear that daily hypocotyl elongation was 0.5mm at +10 DIF, 0.42mm at 0 DIF, 0.2 mm at -10 DIF on the second day of the experiment which was the tenth day after sowing, and daily hypocotyl elongation was enhanced as DIF increased. Analyzing the elongation profiles using image processing, remarkable elongation was observed three hours after the light period started under the +10 DIF condition. The elongation pattern under the 0 DIF condition closely resembled that under +10 DIF, and elongation increased remarkably five hours after the light period started. However, clear elongation was not observed in either the light or dark period under the -10 DIF condition, although some upward tendency was demonstrated 8 hours after the light period started. It was also found that the temporal duration of remarkable elongation under +10 and 0 DIF conditions became longer as DIF increased.
It was demonstrated that daily elongation of Chrysanthemum paludosum ‘North Pole’was mainly influenced by elongation during the light period.

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Stem elongation in Chrysanthemum morifolium Ramat. ‘Reagan’ subjected to various DIF conditions (+10 DIF(day temperature:25°C/night temperature:15°C), 0 DIF (20/20) -10 DIF(15/25)) was analyzed using an image processing system. Fluorescent lamps provided photosynthetic photon flux (PPF) of 150μmolm^-2 s^-1 on the canopy level with a 9h photoperiod. Images of five plants were captured and stored every 10 minutes for 6 days. The stored images were analyzed using subpixel estimation with area based pattern matching. It was observed that daily stem elongation in C. morifolium Ramat. ‘Reagan’ responded well to DIF, and that stem elongation rapidly increased shortly after night began under all DIF conditions. This steep rise continued for approximately 60 minutes, and then the slope of the stem elongation decreased slightly. Stem elongation during the day was 0.5 to 1mm under each DIF condition. However, stem elongation was 3mm or more under +DIF condition, while it was only 1.5mm under a -DIF condition during the dark period. It was found that the tendency toward extension growth was almost determined by the tendency of stem elongation during the night.Another interesting phenomenon was that stem elongation was greater under the lower temperature of 15°C at night under a +DIF condition to a high temperature of 25°C at night under a -DIF condition.

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The objective of this study is to examine the dielectric characteristics of rough rice during the drying process by using time domain reflectometry (TDR) to monitor the wetness of rough rice. Highly moistened rough rice (33.9%-36.8% w.b.) was gradually air-dried, and the TDR waveform during the drying process was monitored by using conventional two-wire and short-ended TDR probes. In the drying process, the moisture content (m) of rough rice decreased gradually with the passage of time and finally attained a value of 11.9% w.b. accompanied by 5% volume shrinkage. Although the TDR waveforms obtained with each probe clearly revealed different traces, the relative permittivity (ε) evaluated from these waveforms generally increased with the moisture content. The high correlation between m and ε (R²=0.95) demonstrates that the m value can be estimated from ε obtained from TDR with sufficient accuracy. To achieve greater accuracy of measurement, a short-ended probe would be more appropriate than a conventional two-wire probe because the former has high sensitivity to changes in ε.

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Effect of DIF (Difference between day and night temperature) on hypocotyl elongation of Brassica oleracea var. acephala. was analyzed by image processing. Experiments were conducted under three DIF conditions,namely 15/25°C, 20/20°C and 25/15°C in growth chambers where photosynthetic photon flux (PPF) of 150μmol s^-1 m^-2 on the canopy level with a 12 h photoperiod was provided by fluorescent lamps. Images of ten plants were acquired every 10 minutes for 5 days and stored for later evaluation.
It was clear that hypocotyl elongation was enhanced as DIF increased and that DIF was effective in Brassica oleracea var. acephala. A characteristic elongation pattern was not observed for each DIF conditions during the light period. However, there were characteristic elongation patterns during the dark period, and remarkable elongation was found during the three hours immediately after the beginning of the dark period under the -10 DIF condition. In 0 and +10 DIF conditions,remarkable elongation occurred for four and nine hours starting one hour after on set of the dark period, respectively. These findings showed that the difference of hypocotyl elongation under DIF conditions occurred during the dark period, and it was found that elongation was particularly remarkable when the temperature during the dark period was low.

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Hypocotyl elongation of French marigold (Tagetes patula, ‘Bonanza Yellow’) under three DIF (difference between day and night temperature) conditions (day temperature(DT): 25°C/night tempereature (NT):15°C, 20/20, 15/25) was analyzed using image processing. Experiments were conducted in growth chambers with a photosynthetic photon flux (PPF) of 150μmol s^-1 m^-2 on the canopy level and a 12 h photoperiod provided by fluorescent lamps. Images of ten plants were acquired every 10 minutes for 7 days and stored for later evaluation. The stored images were analyzed using software developed in-house and applied subpixel estimation to an area-based pattern-matching algorithm. Hypocotyl elongation over 7 days under three DIF conditions (25/15, 20/20, 15/25) ranged from 5.7 to 6.1 mm. There were no significant differences among the conditions, clearly indicating that DIF was not effective for enhancing marigold culture. ANOVA test on hypoctyl elongation during the light period of the second and third day demonstrated a significant difference. However, in the dark period, ANOVA test did not show a significant difference under DIF treatments. Then multiple comparison tests were performed on hypocotyl elongation during the light period,and that under the -10 DIF condition was significantly lower than that during the light period under other DIF conditions. However, since elongation during the dark period of -10 DIF was relatively higher, the daily elongation under the -10 DIF condition was similar to that under the other DIF conditions. It was clearly shown that the cause of not reacting to DIF was almost constant elongation through a single day under 0 and +10 DIF conditions,while under the -10 DIF condition, elongation was decreased during the light period but increased during the dark. Therefore, the daily elongation was almost the same under all DIF conditions.

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The present study was undertaken to develop an effective preservation system for sweet corn kernels by taking advantage of the properties of dim LED light and cool temperature. Dehusked sweet corns (Zea mays L. var. saccharata f. Peter corn) were stored at 5°C for 4 d under a photosynthetic photon flux density (PPFD) of 1μmol m^-2 s^-1 using red and blue LEDs. During storage, the Brix scale was measured daily, and an amino acid analysis was carried out after 4 d storage. The Brix scales were kept high under the blue LED irradiation and cool conditions (5°C) compared to those under dark-cool conditions.Similarly, sweet corn umami was enhanced by storage under the blue LED-cool conditions, which was in good agreement with the observed increase of aspartic acid and glutamic acid, a predominant amino acid, under the same conditions. Red LED-cool conditions had also a preserving effect on sweet corn kernels but not as pronounced as the blue LED-cool conditions. However it was much better than that of dark-room temperature conditions. These results suggest that light quality during storage determines the quality of sweet corn kernel and its umami constituents. The authors propose the blue LED-cool preservation as a practical and useful technique.

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