The wine grapes of Tokachi wine are produced at Ikeda in eastern Hokkaido, where the daily minimum air temperature drops below -20℃ during winter. In this study, we investigated the impact of the previous and current year’s climate conditions (air temperature, precipitations, and sunshine hours) on the fruit quality (Brix, acidity), yield of grapes and Tokachi wine’s vintage evaluation using three varieties ‘Kiyomi’, ‘Kiyomai’, and ‘Yamasachi’ from 1995 to 2016. ‘Kiyomi’ is a clonal selection of the French-derived ‘Seibel 13053’, while ‘Kiyomai’ and ‘Yamasachi’ are cold hardy hybrids derived from crosses of ‘Kiyomi’ and Vitis amurensis. The mean temperature from April to September and rainfall from August to September showed significant positive and negative correlations with the vintage evaluation in Ikeda, respectively, as well as in Bordeaux, France. Brix value of “Kiyomi” was positively correlated with sunshine hours in August and September of the growing year, while its acidity was negatively correlated with the average daily maximum temperature of June and average high temperature of September of the growing year. On the other hand, the Brix value and acidity of ‘Kiyomai’ and ‘Yamasachi’ were strongly influenced by the climatic conditions of the previous year as well as the growing year. Acidity of ‘Kiyomai’ was negatively correlated with the average temperature in June and November of the previous year, while Brix value of ‘Yamasachi’ was positively correlated with the sunshine hours in July of the previous year. In cold regions such as Ikeda, recent global warming has been considered to have a positive effect on agricultural production. However, this study shows that not all conditions associated with warming are positive for Ikeda’s grapes and Tokachi wine.

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　In this study, in order to predict leaf blast occurrence using a leaf wetness sensor, we examined the optimal sensor installation angle and location for the measurement of leaf wetness period in rice plant, the relationship between the wetness period and the occurrence of leaf blast severity, and the optimal threshold of the permittivity of a leaf wetness sensor to determine wetness in rice. The wetness period measured at an installation angle of 0 ° was significantly longer than the wetness period measured at 0 ° to 60 ° angles. Therefore, the optimal setting angle of the leaf wetness sensor was 0 °. There was no significant difference between the wetness period measured in the paddy field and the wet period measured in the plowed field. Therefore, it was considered that it was more practical to install the leaf wetness sensor outside the paddy field in consideration of the labor and maintenance required for the installation. The wetness period measured by the leaf wetting sensor was considered to be applicable to agriculture field sites because the estimation accuracy of the prediction of leaf blast occurrence was high. In rice, the wetting period evaluated at the threshold of 0.300V in permittivity was better than the threshold of 0.284V recommended by METER Group, Inc. to evaluate the occurrence of leaf blast.

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　To evaluate growth and develop a growth model of the medicinal plant Angelica acutiloba, we grew plants of one cultivar in one nursery at nine sites in Honshu and Shikoku, Japan, from 2016 to 2018. The collected data thus reflect differences in growing environment. The model estimates root dry weight and root head diameter from the number of days at the preferred growing temperature range between lower and upper limits based on the daily mean air temperature, and incorporates growth suppression by high temperatures in summer 2018. It was used to develop a program for estimating the optimum harvest date at any location in Honshu and Shikoku from Agro-Meteorological Grid Square Data of NARO.

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　To investigate the effect of heterosis between F1s (F1:First filial generation) and their parents, we investigated the differences of canopy surface temperature (T_c) among six sugar beet genotypes.
　Three of the genotypes: “NK195BR”, “NK235BR” and “NK388” were tested as parents, while the other three “NK235BR×NK195BR”, “NK195BR×NK388” and “NK235BR×NK388” were tested as F1s.
　The diurnal variation of T_c was maximal between 10:00 and 14:00. The maximum difference among genotypes was about 2.7 ℃ in daytime and the T_c of “NK195BR×NK388” showed the lowest among the other genotypes in 103 days after transplanting. The differences of T_c among genotypes increased with increasing vapor pressure deficit. Comparing the 6 hours mean T_c value of six genotypes from 10:00 to 16:00 and in descending order of its value, the results showed “NK388” > “NK235BR” > “NK195BR” > “NK235BR×NK195BR” > “NK235BR×NK388” > “NK195BR×NK388”. Although there was a trend that the yield of F1s was higher than that of their parents with high T_c, it is necessary to clarify the relationship between T_c and yield in the future.

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　The weather and climate of two mountains were estimated using the AMeDAS, aerological data, etc. A cold front passed over on the Sea of Japan on October 24, 2015, bringing fog with severe wind and soft rime on trees to Mount Kusatsu-Shirane (Mt. K) at 2171 m on October 25 and fine soft rime with strong winds to Mount Azumaya (Mt. A) at 2354 m on October 26. The minimum and maximum air temperatures were estimated to be -5.1°C and 1.9°C, respectively, on Mt. K on October 25 and -4.7°C and 8.3°C on Mt. A on October 26. The minimum relative humidity was estimated to be 18% at both locations, and was observed to be 3% on Mt. Fuji on October 25 and 26. The maximum wind speed and maximum instantaneous wind speed were estimated to be 16.5 m/s and 35.2 m/s, respectively, with northern winds on Mt. K on October 25, and 10.1 m/s and 21.9 m/s with north-western winds at Mt. A on October 26. On October 25 and 26, it was estimated that the airstream from the Sea of Japan converged at the Mikuni Mountains and that the wind primarily descended from mountain passes on the east side of the Mikuni Mountains, arriving as an isthmus wind in the Minakami-Numata valley, then passed through Maebashi to the Kanto Plains, arriving as a local wind Karrakaze. A higher-speed wind with the opposite south direction blew at Minakami, and a high-speed wind of the original north direction passed over the Mikuni Mountains. The air temperature of the wide stream from the Sea of Japan decreased with elevation at the Mikuni Mountains and, after the airstream passed over the mountains, it blew into the Kanto Plains as a typical bora wind with low air temperature.
　This paper introduces a simple estimation procedure based on an analysis of the alpine weather and climate at Mounts Kusatsu-Shirane and Azumaya.

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　This study aimed to propose an effective positions of CO₂ supply in tomato plants grown by high-wire system to reduce CO₂ leakage from a naturally ventilated greenhouse. CO₂ was supplied at two different positions within the tomato canopy, and CO₂ concentration was measured at different heights above the ground within or outside the canopy under ventilated or unventilated conditions in the greenhouse. CO₂ supply started below 400 µmol mol^-1 of the CO₂ concentration measured at 2.4 m above the ground and stopped at 450 µmol mol^-1. When CO₂ was supplied at the base of the canopy (0.6 m above the ground), the CO₂ concentration near the top of the canopy (2.4 m above the ground) was below 400 µmol mol^-1 in some cases. On the other hand, when CO₂ was supplied at the middle layer of the canopy (1.2 m above the ground), the CO₂ concentration within the canopy (1.2 to 2.4 m above the ground) was maintained around 450 µmol mol^-1 regardless of ventilated or unventilated conditions. The CO₂ concentration below the roof windows (4.2 m above the ground) was hardly increased by changing the position of CO₂ supply from 0.6 to 1.2 m above the ground. The CO₂ concentration at 4.2 m above the ground under unventilated condition was slightly above 400 µmol mol^-1, which was almost the same as that under ventilated condition. In summary, it was suggested that the CO₂ supply at the middle layer of the canopy was more appropriate than at the base of the canopy to elevate the CO₂ concentration within a canopy of tomato grown by high-wire system. In addition, the CO₂ supply at the middle layer of the canopy was seemed to have a low CO₂ leakage from the top windows even in the ventilated greenhouse.

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