The susceptibility of Fukuoka-bred pear cultivar ‘Gyokusui’ to major diseases, such as Japanese pear scab, and pear anthracnose, was investigated. Leaf susceptibility of ‘Gyokusui’ to Japanese pear scab disease was as high in young leaves as in ‘Kosui’ and ‘Hosui’ but tended to become lower with increasing leaf age. Fruit susceptibility of ‘Gyokusui’ was similar to that of ‘Kosui’ and ‘Hosui’ from flowering to the young fruit stage but lower than that of ‘Kosui’ during the fruit set. ‘Gyokusui’ was slightly less susceptible to pear anthracnose than ‘Hosui’. The disease control system for this variety, therefore, can be adapted for both ‘Kosui’ and ‘Hosui’.

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We evaluated the efficacy of herbicide-based control systems against naturalized morning glory species such as three-lobe morning glory (Ipomoea triloba L.) and pitted morning glory (Ipomoea lacunosa L.), in soybean fields. Treatment with whole-surface, leaf-and stem-applied herbicides imazamox ammonium salt solution and bentazone solution were effective against both species from the emergent stage to the 2L stage, and treatment with fluthiacet-methyl emulsion was effective from the emergent stage to the 4L stage. In soybean fields infested with three-lobe morning glory and pitted morning glory, sowing methods and soil-mixed trifluralin emulsion treatments were effective against both species, although there was no difference between one-step sowing with partial shallow tilling and standard two-step sowing methods. However, the number of germinated plants and the residual amounts of both species were reduced to less than half of those in control systems that excluded soil-mixing. In addition, the control systems that included soil-mixed trifluralin emulsion, soil-applied herbicide, and two applications of a foliar herbicide reduced the residual weed volume of these two species of morning glory (three-lobe morning glory and pitted morning glory) by 1-16% compared to treatment with only soil-applied herbicide.

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A two-year experiment was conducted in a greenhouse to compare the effects of a single basal application (SBA) of coated urea fertilizer with that of conventional fertilization (CF) on the yield and fruit quality of tomatoes. The nitrate-nitrogen concentration in the soil under SBA was less than that under CF during the cultivation period. The total yield, rate of marketable fruit production, and average fruit weight were very similar. Although it was necessary to apply a basal fertilization and additional fertilization 5–8 times during the cultivation period under CF, a single basal fertilization only was applied before planting under SBA, reducing the working hours by 32 h/1,000 m2. In addition, the fertilization cost of SBA was lower than that of CF. Therefore, SBA could become a popular fertilization method for forced tomato cultivation.

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We investigated the effects of a joint V-shaped trellis training system (JV) on early tree growth, fruit productivity, and labor-saving effects of the new Japanese pear, ‘Gyokusui’, up to the fifth year after planting. JV resulted in more shoots per square meter and greater shoot length, indicating that lateral branches were secured at an early stage. The number of flower buds per square meter in the JV treatment was more than that in the two-branch treatment. Furthermore, the yield per 10a was 1.0 t in the third year after planting, and the total yield in the third to fifth years after planting was 4.4 t, which was 6.2 times higher than that of the two-branch training system. The time required per 1t/10a for pruning and pulling, the most time-consuming tasks in pear cultivation, was 29% of that for the two main branches in JV and 54% of that for managing shoots. Furthermore, the evaluation of work posture using the RULA method showed that the percentage of workers with a score of ≥5, which is a high physical load, was low in the JV group, indicating light work. These results indicate that the JV of ‘Gyokusui’ is an early, high-yielding, labor-saving, and light-working cultivation method compared to the conventional two-branch system.

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Selective sampling has been widely adopted for stand-volume estimation. However, the accuracy of this method is low, owing to the variability of the investigator’s experience and subjectivity. To address this limitation, we developed a new method for stand-volume estimation by correcting the selective sample method based on the data of the tree height and determining the spatial distribution of each tree in the forest stand by using unmanned aerial vehicle-structure from motion (UAV–SfM) images. We selected a Sugi plantation to test the effectiveness of the new method for stand-volume estimation. Furthermore, the stand-volume was calculated from the LiDAR data of the region. A 3D model was constructed based on UAV images; the mean tree height and stand-volume were also determined from these images. The stand-volume estimated using the selective sampling method was corrected using the data obtained from the UAV-SfM images. The improvement rate of the estimation accuracy was defined as the percentage of the interval of stand-volume estimation compared to the interval considered for the selective sample method; the estimations conducted using the selective sample method were corrected for the mean tree height and stand volume derived from UAV-SfM images. The new method improved the accuracy of the stand-volume estimations; notably, the accuracy of the estimations conducted using the data corrected based on the stand-volume was higher than that based on the mean tree height.

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In this study, we aimed to assess bamboo distribution via pixel-based image classification of aerial photographs. The study area was the Tachibana Town, Yame City, Fukuoka Prefecture. Aerial photographs taken in June, 2016 and October, 2021 were used for the analysis. A model was constructed to classify the images into “bamboo,” “forest,” and “others” categories using the random forest machine learning method. The overall accuracy of the model was 96% in June, 2016 and 91% in October, 2021. Feature importance analysis revealed visible blue light and red light bands from ortho-rectified aerial photographs processed with a 51×51 averaging filter as the most important features to determine bamboo distribution. The high accuracy observed in June, 2016 was possibly due to the photographs being taken during the bamboo leaf-shedding period. However, in October, 2021, many photographs in the “bamboo” and “forest” categories were misclassified. Overall, these findings suggest that aerial photographs taken during the leaf-shedding period are the most suitable to assess bamboo distribution. As the Fukuoka Prefecture conducts aerial photography of the same area every five years, long-term changes in bamboo distribution can be effectively monitored using aerial photographs.

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To reduce air-conditioning costs for Bunashimeji cultivation, we bred a thermotolerant and tasty strain. In the first stage, ‘Hm379-132’ was selected from 1973 progenies in six half-sib families of ‘Oki Oh-494’ (former strain of ‘Hakata Bunashimeji’) via cultivation tests exposed to higher temperature during spawn-running. In the second stage, ‘Fukuoki173’ was finally selected from 200 progenies in the cross between ‘Hm379-132’ and ‘Oki IB87’ (tasty strain), because ‘Fukuoki173’ met the criteria in the cultivation tests and showed significantly higher palatability with lower bitter taste than ‘Oki Oh-494’ in the organoleptic test. Compared to ‘Oki Oh-494’, the yield of fruit-body of ‘Fukuoki173’ was equivalent at 25°C and significantly higher at 30°C during spawn-running. The harvest period of ‘Fukuoki173’ that spawn-run at 20°C and 25°C was significantly shorter than that of ‘Oki Oh-494’. Furthermore, the warts on the pileus were hardly observed in ‘Fukuoki173’. The colors of pileus and stipe of ‘Fukuoki173’ were light grayish brown and dullness-free white, respectively. Eight bitter amino acid contents in ‘Fukuoki173’ were consistently lower than those of ‘Oki Oh-494’, which was consistent with the results of the organoleptic test. ‘Fukuoki173’ has been applied for variety registration and shipped to the domestic markets since September 2023.

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In greenhouse cultivation of fig 'Toyomitsuhime', low sugar content and abnormal mature fruit that occurs during the hot season on vigorous trees can be prevented by maintaining soil moisture tension below pF2.2 from 7 days before to the end of harvest, keeping the basal diameter between two and three nodes of the bearing branch less than 20 mm, girdling the basal portion of branches with a basal diameter greater than 20 mm in a circular pattern, and the fruit sugar content can be maintained at a higher level than that without treatment. In addition, the half-opening of the roof from the eaves side can lower the temperature inside the greenhouse to the same level as the outside temperature during sunny summer days, reducing the occurrence of abnormal fruit maturation.

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We investigated the ethylene sensitivity of the annual herbaceous flowers matricaria, nigella, and silene during winter and examined the effects of various preservatives on their vase life. Ethylene sensitivity was evaluated using ethylene concentrations of 1 and 10 μL·L−1 for 1 and 3 days. The vase life of matricaria ‘Single vegumo’ was unaffected by ethylene. For nigella ‘Miss jekyll’, ethylene had no impact after 1 day of treatment, but after 3 days, the sepals abscised and vase life was shortened, regardless of the concentration. For silene ‘Sakurakomachi’, vase life was shortened after a 1 day treatment with 1 μL·L−1. As preservatives, STS and Misaki Farm, a commercial preservative, were used for pretreatment, and GLA was applied as a posttreatment. Misaki Farm did not have any effect in three varieties. In matricaria, STS had no effect, whereas GLA extended vase life. In nigella, 0.2 mM STS extended vase life, while GLA had no effect. For silene, STS concentrations of ≥0.1 mM caused leaf phytotoxicity, whereas 0.05 mM STS applied for 6 h caused no phytotoxicity and extended vase life. GLA post-treatment was also suggested to further extend vase life.

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