The drainage effect of connecting open ditches and mole drains in upland fields converted from paddy fields, and the drainage and irrigation effects of open ditches during dry weather on soil moisture and yield of soybean were examined. Using this method irrigation during dry conditions reduced soil pF values. Therefore, soil moisture could be controlled within the effective range for reducing drought damage. In the case of rainfall of 60 mm/day or more, the minimum value of pF was higher with the installation of connecting open ditches and mole drains than without. In 2017, the effect of drainage measures ensured growth volume from the first half of the growing season. In 2018, the first half of the growing season was extremely dry, and multiple irrigations during the dry period with a pF of 2.5 or higher resulted in a higher number of nodes, whole grains, heavier one-hundred-grain weights, and higher yields compared to no installation.

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We investigated the applicability of joint V-shaped trellis (JV) to Japanese persimmon ‘Soshu’ and ‘Fuyu’, to achieve early high yield and labor-effective. The joint V-shaped trellis were planted with one m space between the plants and four m space between the rows. The major branches were joined at a height of 60 cm at the same time as planting, and the side branches were arranged at an elevation angle of 60°. The cumulative yield for the four years from the third to sixth year after planting in the JV were 8.5 and 6.0 tons per 10a for ‘Soshu’ and ‘Fuyu’, respectively, which were 8.3 and 6.0 times higher than those in the conventional open center natural form. The working time per 10a for the major tasks of persimmon cultivation, such as bud thinning, fruit thinning, harvesting, and pruning, also reduced to 49.0% and 30.5% in the open centered natural form of ‘Soshu’ and ‘Fuyu’, respectively. These results suggested that JV is a cultivation method that can achieve early high yield, and labor saving in ‘Soshu’, which has a challenge of early fruit drop, and in ‘Fuyu’, which has the largest cultivated area in Japan.

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The effects of harvesting time and girdling methods on fruit quality of kiwifruit ‘Amawi’ (Actinidia chinensis (Planch.) var. chinensis) were analyzed. Four independent harvest surveys in the five orchards showed soluble solids concentration at harvest reached around 9% from October 28 to November 4 in 2021, and after ripening it also tended to increase as the harvest period was delayed. The h-value of flesh color after ripening tended to decrease as the harvest period was delayed, and the h-value was below 100 in October 28, and the fruit color improved from green to yellow. There was a negative correlation between the accumulated temperature under the trellis from the day of full bloom to the harvest date and post-ripening flesh color, with the flesh color h value reaching 100 when the accumulated temperature reached approximately 3,800°C. In addition, when a one cm-wide girdling method was applied to the base of major or lateral branches at the beginning of September, the post-ripening flesh color tended to turn yellow compared to the non-treated area. These results suggested that harvesting after sixth half of October and applying girdling methods are effective in improving fruit quality of ‘Amawi’.

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In order to elucidate the status of carcass fatty acids in ‘Hakata Wagyu Beef’, we investigated the fatty acid composition of carcass intermuscular fat of 514 steers and 89 heifers. Compared to steers, heifers had significantly higher rate of oleic acid and monounsaturated fatty acids (MUFAs). Regarding the relationship with slaughtering time, the ratio of MUFAs in steers slaughtered in October to November was significantly higher than March to May. Regarding the relationship with slaughtering age of month, there was no significant difference in oleic acid and MUFA ratios in both steers and heifers. Regarding the relationship with blood fatty acid composition, a positive correlation was observed between carcass oleic acid and MUFA with blood palmitic acid and oleic acid. On the other hand, carcass oleic acid and MUFA showed a negative correlation with blood linoleic acid. This study clarified the actual fatty acid composition of carcass of ‘Hakata Wagyu Beef’ and the effects of slaughtering age in month and slaughtering time on carcass fatty acid composition. We also found a certain correlation between carcass fatty acid composition and blood fatty acid composition.

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The aim of this study was to examine the effect of controlling nutritional status (i.e., low to high nutrition) on the following outcomes in Japanese Black cows: 1) the number of small and medium follicles in the ovaries, 2) the response to superovulation, and 3) the number of normal fertilized oocytes. Specifically, nine Japanese Black cows were fed a low nutritional diet for two weeks (TDN:90%, CP:100%) and then they were subjected to a high nutritional diet (TDN:115%, CP:140%). Finally, after one week, CIDR was inserted. In addition, superovulation treatment, periodic artificial insemination, and uterus flashes were performed. Moreover, the control group was fed the standard nutrients (TDN:106%, CP:110%) for the same period as the test group. Throughout the study, the test and control groups did not differ in terms of their body weight. Although the number of small and medium follicles did not change during the low-nutrition period, this number significantly increased when a high-nutrition diet was implemented. However, the number of large follicles (i.e., as driven by superovulation) was not different between the two groups. Regarding the uterus flash results, there was no difference in the number of oocytes obtained during embryo collection, but the number of normal fertilized embryos was significantly higher in test group (P<0.05). We also found that the number of non-fertilized oocytes was significantly lower in the test group. Overall, we found that pre-superovulatory nutritional control in Japanese Black cows contributes toward the small-medium follicle, but this approach does not affect follicular development responsiveness after superovulation. We also found that pre-superovulatory nutritional control may reduce the rate of non-fertilization and increase the number of normal fertilized embryos.

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To establish a labor-saving cultivation method, we investigated the effect of espalier-training on tree growth and the improvement of working posture of grape rootstock mother trees. The trunk of ‘Kober 5BB’ grown by espalier were 55cm, compared to those grown by trellis training of 172cm. The result showed that the working time did not differ between trees grown by espalier and trees grown by trellis training. In shoot management, the forward bending work time in espalier section was 6 minutes 6 seconds longer than trellis training section, while raising arm work time in espalier section was 60 minutes 33 seconds shorter than in trellis training. The total time of the forward bending and raising arms above the shoulders in espalier was 13 minutes 29 seconds, which was 67 minutes 56 seconds shorter than in trellis training. There was no difference in the number of scions per the tree. However, the scions per ground area covered by tree canopy in espalier were 72.5, which was more than 7.3 in trellis training. A similar trend was observed for tree growth and other factors on ‘Hybrid franc’. These results suggest that espalier for scion-producing mother trees of grapevine rootstock is a method that reduce the work burden.

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We were able to grow the nursery stock of Japanese pear ‘Gyokusui’ grafted on Pyrus calleryana for a tree joint V-shaped trellis system in one year, which normally takes two years to grow. First, we investigated the optimal sowing time and planting interval for P. calleryana No.6 and No.8. We showed that it was possible to produce rootstocks that could be grafted for 1 year by following the steps P. calleryana No.6 and No.8were sowed in January or February and in June seedlings of P. calleryana No.6 and No.8 were planted at 10 or 20cm intervals in nursery garden. Second, we investigated that shorten training period of‘Gyokusui’ grafted on P. calleryana for a tree joint V-shaped trellis system from 2 years to 1 year by growing in M StAR containers. The nursery stock for a tree joint V-shaped trellis system were made by transplanting one-year-old rootstocks to 4L or 6L M StAR containers in February and grafting them with ‘Gyokusui’ in March.

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When exporting garden tree seedlings overseas, plant-parasitic nematode removal through root washing and chemical treatment (hereafter, referred to as nematode control) is imperative. This study focused on Camellia sasanqua, Ilex crenata, and Pinus thunbergii, examining the impact of irrigation methods and mist intervals on their quality during nematode control in September, when it is considered highly effective for plant-parasitic nematode management. We aimed to identify the optimal irrigation method for garden tree seedlings. If nematode control in September significantly reduces the number of exportable individuals, alternative control periods must be considered, regardless of the September period’s efficacy against plant-parasitic nematodes. Therefore, we investigated quality deterioration occurrences during nematode control in April, August, October, and December, determining the optimal period for nematode control in garden tree seedlings. The results showed that during September control, both hand irrigation and mist irrigation were suitable for C. sasanqua and I. crenata, whereas hand irrigation alone was suitable for P. thunbergii. Considering the peak effectiveness of nematode control during their breeding season from September to October, the optimal control period was September–October for C. sasanqua, October for I. crenata when quality decline was less likely to occur, and September–October for P. thunbergii, despite a 20%–30% quality decline.

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This study aimed to develop methods to maintain quality of greening nursery stock during container transportation for export to East and Southeast Asia, Storage tests were conducted to explore the impact of container type, transpiration control agent application, and packing methods. Post-delivery analysis revealed that Camellia ‘Ikkyu’ exhibited a decrease in percentage of healthy plants when transported in dry containers with transpiration control treatment and plastic bag packing. However, all plants in reefer containers were healthy. Kurume azalea ‘Chikushibeni’ showed a decline in healthy plants in dry containers, whereas the number of healthy plants in reefer containers with plastic bag packing was higher. Sasanqua camellia ‘Kanjiro’, Japanese holly, and Japanese black pine exhibited no wilted or dead plants. These findings indicate that the optimal transportation method varies by species in greening nursery stock. Reefer containers are recommended for camellias and Kurume azaleas, whereas sasanqua camellia, Japanese holly, and Japanese black pine can be cost-effectively transported in dry containers at room temperature.

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We investigated the graft compatibility, ceratocystis canker resistance, and cultivation characteristics in continuous cropping fig fields of by grafting ‘Toyomitsuhime’ fig onto ‘Reikodai 1 go’ (BC1 from interspecific hybridization of Ficus carica L. and F. erecta Thunb.) with true resistance to ceratocystis canker, and clarified the potential using ‘Reikodai 1 go’ as a rootstock. The survival rate of the scion was high when ‘Toyomitsuhime’ fig was grafted onto ‘Reikodai 1 go’ rootstock and was comparable to that of the scion when ‘Toyomitsuhime’ fig was grafted onto ‘Kibaru’ rootstock. The growth of ‘Reikodai 1 go’ seedlings was either comparable to or higher than that of ‘Kibaru’ seedlings, and the graft compatibility was high. ‘Reikodai 1 go’ seedlings of ‘Toyomitsuhime’ fig were not infected and had a higher ceratocystis canker resistance than ‘Kibaru’ seedlings when a suspension of ceratocystis canker spores was poured three times a year for three years into the soil of the cutting grafted seedlings planted in pots. The growth amount of the current shoots, yield, and fruit quality of ‘Reikodai 1 go’ grafted rootstock of ‘Toyomitsuhime’ fig planted in continuous cropping fig fields were higher than those of the own-root trees and comparable to those of the ‘Kibaru’ grafted rootstock. The grafting of ‘Toyomitsuhime’ fig onto ‘Reikodai 1 go’ rootstock is unlikely to cause problems in growth and fruit production, and has proven to be an effective means of avoiding Ceratocystis canker which is the most important disease in fig cultivation.

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