Parallel, Continuous Monitoring and Quantification of Programmed Cell Death in Plant Tissue

Abstract

The accurate quantification of hypersensitive response (HR) programmed cell death is imperative for understanding plant defense mechanisms and developing disease-resistant crop varieties. In this study, we report an accelerated phenotyping platform for the continuous-time, rapid and quantitative assessment of HR: Parallel Automated Spectroscopy Tool for Electrolyte Leakage (PASTEL). Compared to traditional HR assays, PASTEL significantly improves temporal resolution and has high sensitivity, facilitating the detection of microscopic levels of cell death. We validated PASTEL by transiently expressing the effector protein AVRblb2 in transgenic lines of the model plant Nicotiana benthamiana (expressing the corresponding resistance protein Rpi-blb2) to reliably induce HR. We were able to detect cell death at microscopic intensities, where leaf tissue appeared healthy to the naked eye one week after infiltration. PASTEL produces large amounts of frequency domain impedance data captured continuously (sub-seconds to minutes). Using this data, we developed a supervised machine learning models for classification of HR. We were able to classify input data (inclusive of our entire tested concentration range) as HR-positive or negative with 84.1% mean accuracy (F 1 score = 0.75) at 1 hour and with 87.8% mean accuracy (F 1 score = 0.81) at 22 hours. With PASTEL and the ML models produced in this work, it is possible to phenotype disease resistance in plants in hours instead of days to weeks.

Plant phenotyping relevance

植物組織の過敏感反応による細胞死を連続的・定量的に測定する分光計測プラットフォームと機械学習分類モデルを開発・検証しており、植物表現型取得が研究の中心である。

Code and data availability

The supplied blocks describe the PASTEL phenotyping platform, impedance datasets, and machine learning models, but contain no public data or code availability statement, no repository name, and no author-provided public URL. Data processing is described only as being done locally in MATLAB/sklearn/tsfresh, with no de-

No evidence-backed public reproduction asset is currently recorded.