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アイテム
立体栽培スイカの果実生産特性に関する研究
https://doi.org/10.24514/00001753
https://doi.org/10.24514/000017533c1bc3fd-f6f6-4a4d-ada9-32b9a4b4f25e
| 名前 / ファイル | ライセンス | アクション |
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nivts_report_No12p7-60p.pdf (4.7 MB)
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| Item type | 紀要論文01 / Departmental Bulletin Original Article(1) | |||||
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| 公開日 | 2019-03-22 | |||||
| タイトル | ||||||
| タイトル | 立体栽培スイカの果実生産特性に関する研究 | |||||
| タイトル | ||||||
| タイトル | Fruit Productivity of Vertically Trained Watermelon [Citrullus lanatus (Thunb.) Matsum. et Nakai] | |||||
| 言語 | en | |||||
| 言語 | ||||||
| 言語 | jpn | |||||
| 資源タイプ | ||||||
| 資源タイプ識別子 | http://purl.org/coar/resource_type/c_6501 | |||||
| 資源タイプ | departmental bulletin paper | |||||
| ID登録 | ||||||
| ID登録 | 10.24514/00001753 | |||||
| ID登録タイプ | JaLC | |||||
| 著者 |
渡辺, 慎一
× 渡辺, 慎一 |
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| 抄録 | ||||||
| 内容記述タイプ | Abstract | |||||
| 内容記述 | Watermelon [Citrullus lanatus (Thunb.) Matsum. et Nakai] is a major, high-production fruit vegetable in Japan ; its yearly production follows that of cucumbers and tomatoes. It is grown all over Japan, mainly in open fields. Production of watermelon is declining gradually, mainly because of the labor involved in managing conventional crops, whereby shoots are trained horizontally on the ground surface. Recently, vertical training has received attention as an alternative system because of the reduced crop management labor involved. We examined the fruit productivity of vertically trained watermelon plants, with a focus on leaf area, light reception, and field photosynthesis characteristics. We also examined the source–sink relationships of photosynthates during fruit development so as to characterize fruit productivity in vertical training. We compared the working posture required with vertical training systems with that with conventional, horizontal training systems. Chapter II investigates the characteristics of fruit enlargement on vertically trained plants. Initially, we examined the effects of fruit set position on total leaf area per plant and final fruit weight in vertically trained plants. Two primary lateral shoots were allowed to grow on each plant, and one fruit was set per plant. As the fruit set position increased, the fruit weight increased. Total leaf area per plant during fruit development increased as fruit set position increased. Fruit weight at harvest was closely related to total leaf area per plant at 5, 20, and 40 days (harvest) after pollination. We concluded that decreased photosynthetic production due to small leaf area and competitive growth between the fruit and vegetative organs during fruit development caused smaller fruits to develop when fruiting occurred at a lower node position. Next, we investigated the effect of the pattern of vertical training on fruit weight in relation to total leaf area per plant. In-June-harvest and November-harvest crops, one to three shoots were allowed to grow and one fruit was set per plant. In both growing crops, fruit weight was closely related to total leaf area per plant, irrespective of the training pattern. However, the regression lines between fruit weight and total leaf area per plant differed between the growing seasons. There is therefore a need to further investigate light reception to analyze the characteristics of fruit enlargement in vertical training. We investigated the effect of planting density on fruit weight of vertically trained plants in terms of light reception among expanded leaves and photosynthetic production. Two shoots per plant were allowed to grow and were trained vertically, and one fruit was set. Solar radiation on individual leaves was measured during fruit development with an integrated solarimeter film. The photosynthetic rates of these leaves were measured with a portable photosynthesis system. Fruit weight decreased significantly as planting density increased and was closely related to the total leaf area per plant at each planting density. However, the regression lines between fruit weight and total leaf area per plant differed among planting densities. Fruit weight was obviously proportional to both total solar radiation received and photosynthetic production per plant. The change in fruit weight with planting density was attributed to changes in the photosynthetic productivity of the whole plant ; this in turn was a main function of the total solar radiation. The results in chapter II indicate that total leaf area per plant could determine differences in fruit weight in vertically trained plants within a certain range of planting densities or training patterns in the same growing season. However, over a wider range of planting densities or training patterns, or in a different growing season, the total solar radiation received and photosynthetic production per plant are likely to be more appropriate factors than the total leaf area per plant in investigations of the characteristics of fruit enlargement. In chapter III , we use the 13^C-tracer method to investigate the translocation and distribution of photosynthates during fruit development in vertically trained plants with one or two shoots and one fruit. The percentage translocation of 13^C from 13^CO_2-fed leaves exceeded 70% during fruit development, irrespective of the position of the 13^CO_2-fed leaves (except for the lower leaves in the plants with two shoots and one fruit at the late stage of fruit development ; the percentage was approximately 50%). Therefore, most of the photosynthates in the whole plant were transported to the fruit. In plants with two shoots and one fruit, all leaves on the plant were sources of photosynthates translocated to the fruit, whereas leaves on the non-fruiting shoots were also sources of photosynthates translocated to the roots. In plants with one shoot and one fruit, all leaves on the plant were sources of photosynthates translocated to the fruits, whereas a limited number of lower leaves on the main shoot or leaves on the extra lateral shoot ("asobi-zuru" in Japanese) growing from the cotyledonary node were sources of photosynthates to roots. We concluded that fruit weight could be determined by total leaf area, total solar radiation received, and photosynthetic production per plant, because most photosynthates of vertically trained watermelon plants during fruit development were concentrated in the fruit. Chapter IV compares fruit productivity and labor load-especially working posture-between vertically and horizontally trained watermelon planting systems. Initially, we compared shoot growth, fruit enlargement, light-reception characteristics, and field photosynthetic rate between vertically and horizontally trained plants, each with two shoots and one fruit ; a higher planting density was used for vertical training. The training method had little or no influence on shoot growth. Fruit weight was significantly lower in vertically trained plants than in horizontally trained ones, even when the total leaf area was similar. The amount of solar radiation received by, and the photosynthetic rates of, the middle and lower leaves of vertically trained plants decreased gradually with decreasing leaf position and were lower in vertically trained plants than in horizontally trained ones. We concluded that the main reason for the production of smaller fruits on vertically trained plants at the respective planting densities was the lower light reception by the middle and lower leaves on vertical plants than on horizontal ones. We then compared fruit productivity in vertically and horizontally trained plants with two shoots and one fruit in July-harvest and November–December-harvest crops. Fruit weight per the amount of solar radiation receivedby a plant in vertically trained plants was equal to, or greater than, that in horizontally trained plants. As planting density increased, fruit yield per unit land area with vertical training increased and exceeded that with horizontal training. We used a working posture analysis system to evaluate the labor load in disbudding and topping work with vertical and horizontal training systems. Vertical training improved the working posture by decreasing the bending angles of the trunk and thighs ; this was accompanied by a decreased "pain index" (Nagamachi, 1986). The time needed for disbudding work was shorter in the vertical training system than in the horizontal one. From the results in chapter IV, we concluded that vertical training of watermelon plants could improve working posture and increase fruit yield per unit land area under higher planting density than with horizontal training, without loss of light-use efficiency. The finding that most of the photosynthates were distributed to the fruits throughout fruit development suggested that fruit weight or fruit yield per unit land area, or both, could be predicted from estimated solar radiation. It also suggested that fruit weight could be controlled by adjusting planting density or leaf area per plant, or both. We also found that the amount of solar radiation received per plant was likely to be a more useful index than leaf area per plant for estimating fruit production with different training methods, especially when light-interception characteristics differed widely (e.g. between the vertical and horizontal training systems studied here). Use of solar radiation received per plant as an index should help in the development of productive training systems for fruit vegetables in the field. In conclusion, vertical training of watermelon plants increased fruit yield per unit land area under higher planting density than with horizontal training, without loss of light-use efficiency. The vertical training method is favorable for meeting the recent marketing trend for small, high-quality fruit and has the potential to increases the areas under production in Japan, especially in protected cultivation. | |||||
| 書誌情報 |
野菜茶業研究所研究報告 en : Bulletin of the National Institute of Vegetable and Tea Science 巻 12, p. 7-60, 発行日 2013-04-02 |
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| 出版者 | ||||||
| 出版者 | 独立行政法人 農業・食品産業技術総合研究機構 | |||||
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| 収録物識別子タイプ | ISSN | |||||
| 収録物識別子 | 1346-6984 | |||||
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| 関連タイプ | isIdenticalTo | |||||
| 識別子タイプ | DOI | |||||
| 関連識別子 | 10.24514/00001753 | |||||
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| 出版タイプ | VoR | |||||
| 出版タイプResource | http://purl.org/coar/version/c_970fb48d4fbd8a85 | |||||
