彦坂 晶子

The effect of the ratio of red and blue light on fruit biomass radiation-use efficiency (FBRUE) in dwarf tomatoes has not been well studied. Additionally, whether white light offers a greater advantage in improving radiation-use efficiency (RUE) and FBRUE over red and blue light under LED light remains unknown. In this study, two dwarf tomato cultivars (‘Micro-Tom’ and ‘Rejina’) were cultivated in three red-blue light treatments (monochromatic red light, red/blue light ratio = 9, and red/blue light ratio = 3) and a white light treatment at the same photosynthetic photon flux density of 300 μmol m^–2 s^–1. The results evidently demonstrated that the red and blue light had an effect on FBRUE by affecting RUE rather than the fraction of dry mass partitioned into fruits (F_fruits). The monochromatic red light increased specific leaf area, reflectance, and transmittance of leaves but decreased the absorptance and photosynthetic rate, ultimately resulting in the lowest RUE, which induced the lowest FBRUE among all treatments. A higher proportion of blue light (up to 25%) led to a higher photosynthetic rate, resulting in a higher RUE and FBRUE in the three red-blue light treatments. Compared with red and blue light, white light increased RUE by 0.09–0.38 g mol⁻¹ and FBRUE by 0.14–0.25 g mol⁻¹. Moreover, white light improved the F_fruits in ‘Rejina’ and Brix of fruits in ‘Micro-Tom’ and both effects were cultivar-specific. In conclusion, white light may have greater potential than mixed red and blue light for enhancing the dwarf tomato FBRUE during their reproductive growth stage.

We propose a platform called “LCA-Multidimensional Map (LAMP)” to support companies and individuals aiming for CO2 zero emissions (CZEs) by efficiently conducting life cycle assessments (LCAs) of their products and activities, collecting information necessary for CZEs, and developing CO2 reduction plans. LAMP is a multidimensional platform that supports the development of CZEs targets in cyberspace without temporal or spatial constraints. Using this software, LCAs can be conducted using existing database groups constructed in two and three dimensions in various sectors as well as data groups with temporal information, such as evolving and continuous records, and spatial information in a cross-sectional manner. Furthermore, based on the LCA results, CO2-emission-reduction plans can be formulated (extraction of alternatives), and their effectiveness can be confirmed through LCA again. As an example of how to use LAMP, we introduce the characteristics of LCA in horticulture, the second-largest source of CO2 emissions after livestock in the agricultural sector, along with examples of alternative plans for greenhouses, collaboration plans with other sectors, and basic methods for promoting CZEs in horticulture. Although this concept needs to be tested and validated in the future, it might encourage individuals or companies to cooperate in LAMP development or inspire them to advocate for more progressive ideas.

type:text [ABSTRACT] In 2021, we started the new project for viticulture by plant factory with artificial light. However, there are various technical issues, which specified to the woody species, should be overcome for the achievement of viticulture in plant factory with artificial light. Here, we first review the current practice and several technologies for viticulture in plant factories with sunlight and find out the technical issues that need to be overcome to establish viticulture by plant factory with artificial light. Next, we discussed １) the state-of-the-art knowledge about plant monitoring using remote sensing, and ２) the technologies applied to various horticultural crops in plant factory with artificial light practical. These relevant research observations indicate the future breakthrough technologies, which we should develop throughout our new project, for viticulture in plant factory with artificial light. [抄録] 人工光植物工場を活用したブドウ生産の実現には，木本植物である果樹に特有の技術的に検討すべき課題が多く存在する．そこで本稿では，まず太陽光利用を含めた植物工場におけるブドウを中心とした果樹生産の現状を俯瞰することで，人工光植物工場でのブドウ生産の実現に向けてブレークスルーすべき技術的な課題を提示する．次にリモートセンシングを利用した植物モニタリングの最先端の知見を解説するとともに，様々な園芸作物における人工光植物工場における技術を議論することで，2021年度園芸フロンティア研究プロジェクトにおいて推進中の「植物工場でのブドウ栽培を実現する先進的果樹栽培技術の確立」において開発を目指す技術の一端について紹介をする．