This study was conducted as a first step in the development of the robotic harvesting system for eggplants. The robotic harvesting system with hand-eye structure was fabricated and the visual feedback fuzzy control model to operate the manipulator was developed. The control model was examined in terms of manipulator guidance to the fruit, estimation of the fruit maximal diameter for selective harvesting and estimation of the fruit angle for the picking movement. From the results of the approach experiment, the control model enabled the manipulator end to reach a fruit 300 mm away with 6 to 10 feedback signals. The manipulator trajectory varied in vertical direction with fruit location and the control model actuated the manipulator end slightly upward than the target region. The control model could estimate the fruit maximal diameter with an accuracy of 29.0±17.9%. However, it still has a low standard of performance as a visual sensor for selective harvesting. Moreover, it could estimate the fruit angle in row direction with an error of 3.6±2.60. The visual feedback guidance ot the manipulator was confirmed to be an effective method for a robotic eggplant harvesting.

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Development of an effective, high-power, low-cost, artificial light source for use in plant-growing facilities would be very beneficial for plant production.
Recently, the laser-diode lamp has been proposed as a new type of light source for plant production. The advantages of the laser-diode lamp over conventional light sources are its high electrical-to-optical power conversion efficiency, low thermal radiation, easy set-up for high power and pulse irradiation, small weight and small volume for mounting, and selectivity for proper wavelength.
Because laser light itself differs from the light sources presently used in plant growing, we confirmed the possibility of growing plants under the laser-diode light by growing lettuce
(Lactuca sativa L.) plants.Lettuce seedlings with 5-6 leaves were grown under a laser-diode lamp panel with 30 pieces of high-power and high-efficiency AlGaInP laser-diodes. The power of each laser-diode lamp was 500 mW, and the wavelength was 680 nm, which was efficient for photosynthesis.
The lettuce plants were able to grow under the laser-diode light. However, the weight of the lettuce plants grown under the laser-diode lamps was light, and their leaves were long and thin compared to those of lettuce plants grown under high-pressure sodium lamps.

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The LISA (Low-Input Sustainable Agriculture) program was launched to reduce the use of off-farm inputs with the greatest potential to harm the environment or the health of farmers and consumers. This is one of the operational definitions of sustainable agriculture. However, LISA has not gained appreciable support from the agricultural sector, since the nature of LISA decreases profits. On the other hand, the implementation of Precision Agriculture (PA) has been embraced. The difference between PA and LISA is that PA requires technological innovation, whereas LISA always involves revising or improving traditional practices. The extensive application of information technology, including GPS and GIS, to agriculture, and the development of agricultural machinery for PA are major factors for the difference between PA and LISA. The machinery includes equipment to implement variable rate technologies, and vehicles specifically designed to gather the information required to generate yield and soil maps.
There are quite a few plant factories operating commercially in Japan. PA is nothing but integrated technology, designed to optimize the cultivation process. The fully controlled environment of a plant factory can be considered as an ideal cultivation system in terms of alternative agriculture. Most of the environmental factors in a fully controlled plant factory are observable and controllable; a plant factory can be optimized more easily than an open field. Microprecision agriculture can be attained by using plant factories to realize profitable alternative agriculture. This article reviews the scientific and technological achievements of plant factories as alternative agriculture, and introduces a hardware system developed to implement microprecision agriculture in a plug seedling production factory.

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キュウリの生育にともなう蒸散量の変化に応じて給液量を制御する閉鎖型ロックウール養液栽培において, キュウリ水耕栽培の汎用処方 (リン, カリウム, カルシウムおよびマグネシウムはそれぞれ3, 6, 7および4me・liter^-1) を用い, 培養液の窒素濃度を4, 13, 22me・liter^-1の3区に分けて栽培を行い, キュウリの生育, 培養液の栄養成分変化および葉中の無機成分含有率について調査した.
低N区は, キュウリの生育が極めて貧弱であり, 主枝葉中の各無機成分含量が少なかった.標準N区に比べ, 高N区は茎, 葉の新鮮重, 収量および培養液の供給量とも少なかった.
培地の窒素は高N区では結果中期から著しく集積したが, 標準N区では結果後期にやや集積した.リン濃度は結果初期以降各区ともほぼ無で推移した.標準N区と高N区ではカリウムは結果後期に, カルシウムおよびマグネシウムは結果前期から多く集積した.
主枝節位別の葉中の窒素含有率は, 標準N区では上位葉, 高N区では中, 上位葉が高く, リン含有率は培養液の窒素レベルに正比例し, 下位葉ほど低かった.一方, カルシウムとマグネシウム含有率は培地の塩分集積につれて生育段階が遅い上位葉ほど, また高N区で低かった.カリウムは中, 上位葉でこの傾向がみられた.これらの結果から, 閉鎖型養液栽培には生育に応じた栄養成分の均衡を保つ必要が明らかとなった.

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There are two methods of making a general nutritional diagnosis of plants. One is a visual diagnosis based on experience, and the other is a sap analysis of a stems and leaves. Many years of training and experience are needed to make a visual diagnosis, whereas the chemical analysis of a sap also takes a long time to obtain results.
Therefore, we have studied the relationship between leaf electric potential and the nutritional condition of plants. We found that the inorganic nutritional condition (N, P, Mg) of a tomato can be diagnosed by examining of the three dimensional distribution of three alternating current components (30.0, 13.0 and 20.0Hz) of leaf electric potential.

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In Akita prefecture, cherry bark is used for traditional industrial purposes (so-called kabazaiku). It is basically necessary to evaluate the bark of the tree for breeding and silviculture.
In the present study, we established a bark evaluation method that can be used with ease. From the observation of 3 mountains with cherry tree growth, it was seen that the cherry trees located on the ridge side were shorter and had smaller diameters and thiner bark compared to those on the valley side.
Using principal components analysis, the bark from 8 locations of 3 mountains could be classfied into 4 types. Moreover, the cherry tree height, bark thickness, and healthiness are correlated to the diameter of the tree. The height and the bark thickness can be estimaed by a single regression formula, using the tree diameter as the explanatory variable, but the bark healthiness cannot allow such estimation.
It was suggested that the cherry bark thickness and the healthiness are genetically and environmentally regulated.

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本報では, きのこの栽培調整や形状制御を可能とする環境制御のための適正な設備投資を目指し, これまでの研究成果にもとづき, 環境制御状態と空調機稼働状態を示すシミュレーションソフトを開発するとともに, 栽培瓶数15万本クラスの標準的規模のきのこ工場を例にとり, 栽培環境制御の実態を明らかにした.
1.現状のきのこ栽培室では, きのこから発生した炭酸ガスを外気で希釈してるので, 外気導入により, 夏季昼下がりはわずか1～2分, 冬季明け方は2～6分で室内環境が不適正になる.したがって, きのこと他の野菜類との同室栽培により炭酸ガス濃度の調整を行い, 設備投資を抑えることが重要な課題である.
2.夏季昼下がり, 栽培室は0.5m³/s換気扇, 21kW冷房機により, 炭酸ガス濃度 (4352, 4468, 4585) ppm, 温度 (21.7, 21.9, 22.0) ℃, 湿度 (98.0, 99.3,100.0) %に制御できた.このとき, 実際の幾多の工場で発生しているようなパワー過不足を生じなく適正環境となる.また加湿器は必要なかった.稼働率は換気扇89.2%, 冷房機96.2%であった.
冬季明け方, 冷房機を使用しないと温度が目標上限を若干越える (約0.2℃, 3～4min/h).0.5m³/s換気扇, 21kW冷房機, 6kW暖房機, 19kg/h加湿器を使用すれば, 湿度は (67.6, 68.6, 70.0) %になるが, 夏季と同様に適正に制御できた.稼働率は換気扇89.2%, 冷房機5.6%, 暖房機86.4%, 加湿器92.1%であった.

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ニンジンのカロテノイド色素をフォトダイオードアレイ検出器を用いた高速液体クロマトグラフィー (HPLC) により分析した.カロテノイドはフィトエン, フィトフルエン, ζ-カロテン, α-カロテン, β-カロテンおよびキサントフィル類が検出され, β-カロテンの占める割合が多かった.カロテノイド含量は心部より肉部で高い値を示した.肉部のβ-カロテン含量は'MK-D548'が最も多く, ついで'レッドプリンス', '陽州五寸', 'はまべに2号'の順であった.β-カロテン含量の多い品種はa値もやや高い傾向にあった.

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