最近，来自以色列的科学家利用Plantarray系统发表根腐烂导致植物光谱叶片反射变化的文章，文章题为Pepper Plants Leaf Spectral Reflectance Changes as a Result of Root Rot Damage，文章发表在知名期刊Remote Sens. 2021,13(5), 980;https://doi.org/10.3390/rs13050980上。

摘要

根部胁迫症状变化很难通过无损工具进行检测。本研究揭示了植被指数（通常用于感知冠层状态）检测根部胁迫的能力以及性能状态。辣椒植物在可控温室条件下，在不同钾和盐胁迫处理下种植。在实验最后一天测量植物光谱反射，其时，超过多半的植物已经自然感染了根病。利用光谱测量计算的植被指数用于检测健康以及根部损伤植物。尽管在叶片没有检测到可视症状，植被指数和红边位置显示出了健康与根感染植物的清晰的差别。结果在生长32天后获得，揭示可利用早期生长阶段叶片反射率来检测根部损伤。 

The pots’weight was logged every three minutes by computerized weighing lysimeters, using PlantArray 3.0 (www.plantditech.com). The  system was used to calculate the daily plant weight and daily transpiration [32]. The plant weight was calculated by reducing the pot and growing medium weight from the fifinal

weight. The pots were covered with a custom cap that only allowed the shoot stem through it, which enabled us to determine the daily transpiration. The irrigation was only applied at night. Thus, the daily transpiration was calculated as the weight difference between the early morning weight and the evening weight; no irrigation was applied during that time. PlantArray 3.0 was also used for logging daily photosynthetic active radiation (PAR) and vapor pressure defificit (VPD)

Pepper Plants Leaf Spectral Reflectance Changes as a Result of Root Rot Damage

by Shahar Weksler 1,2,*,Offer Rozenstein 2,Nadav Haish 3,Menachem Moshelion 3,Rony Wallach

 4andEyal Ben-Dor 1

1 Porter School of Environment and Earth Sciences, Faculty of Exact Sciences, Tel Aviv University (TAU), Tel Aviv 6997801, Israel

2Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Rishon LeZion 7528809, Israel

3The Robert H Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot 7610001, Israel

4Department of Soil and Water Sciences, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel

Author to whom correspondence should be addressed.

Academic Editor: Arturo Sanchez-Azofeifa

Remote Sens. 2021, 13(5), 980; https://doi.org/10.3390/rs13050980

Abstract

Symptoms of root stress are hard to detect using non-invasive tools. This study reveals proof of concept for vegetation indices’ ability, usually used to sense canopy status, to detect root stress, and performance status. Pepper plants were grown under controlled greenhouse conditions under different potassium and salinity treatments. The plants’ spectral reflectance was measured on the last day of the experiment when more than half of the plants were already naturally infected by root disease. Vegetation indices were calculated for testing the capability to distinguish between healthy and root-damaged plants using spectral measurements. While no visible symptoms were observed in the leaves, the vegetation indices and red-edge position showed clear differences between the healthy and the root-infected plants. These results were achieved after a growth period of 32 days, indicating the ability to monitor root damage at an early growing stage using leaf spectral reflectance. 

Keywords: reflectance; root rot; transpiration; red-edge