Determining the traits of drought tolerance in tomato seedlings using energy and water balance

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K15942
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 41040:Agricultural environmental engineering and agricultural information engineering-related
• Research Institution: Ehime University
• Principal Investigator: Fujiuchi Naomichi 愛媛大学, 大学院農学研究科, 助教 (90791210)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 細胞壁弾性率 / 蒸散モデル / 通水コンダクタンス / プレッシャーチャンバー / 水ポテンシャル

Outline of Final Research Achievements

I have tried to calculate the traits of drought tolerance by solving the equations of energy balance and water balance under unsteady state. However, we observed an energy balance error that was difficult to solve within the scope of this research. Therefore, we took a different approach: quantifying the trains of individual leaf and modeling the individual-leaf and whole-plant transpiration. We developed an equation of the time course of water efflux rate from the petiole of the leaf which lamina was pressurized quickly in a pressure chamber. The equation contained the hydraulic conductivity and the proportional constant for bulk modulus. These parameters can be calculated at the same time by applying the equation to the measured water efflux rate. Moreover, we developed a model with the parameters and a negative feedback loop of transpiration rate. These technique and model will contribute to the control of water and nutrient supply.

Free Research Field

農業環境・情報工学

Academic Significance and Societal Importance of the Research Achievements

植物の膨圧維持能力や気孔調節能力などの水保持・蒸散に関連する形質は，乾燥耐性向上のための育種のターゲットとなり得るのみならず，水ストレス付与による農産物高品質化においても付与すべきストレス強度を見積もる上で重要である。本研究では，ネガティブフィードバックループを備える個葉蒸散モデルを開発し，そこで定義されたパラメータのうち個葉の通水コンダクタンスと弾性率比例定数を同時に定量することができる回帰式と実験方法を開発した。個葉ごとにこれらの値を定量することで，変異体形質評価や植物体蒸散モデルの高精度化が可能となる。