Method for evaluating vitality of plant, and measurement system and evaluation system

Patent metadata

Field	Value
Publication number	US-10024832-B2
Application number	US-201414277209-A
Country	US
Kind code	B2
Filing date	May 14, 2014
Priority date	May 17, 2013
Publication date	Jul 17, 2018
Grant date	Jul 17, 2018

Abstract

The present invention discloses a method for evaluating vitality of a plant including (a) a step of measuring a delayed luminescence of a leaf of each plant of a group of plants subject to evaluation to obtain data of delayed luminescence amount, and (b) a step of processing data of a plurality of delayed luminescence amounts thus obtained to evaluate a plant exhibiting a delayed luminescence amount not less than a preset upper limit threshold as an individual of poor growth or evaluate a plant exhibiting a delayed luminescence amount not more than a preset lower limit threshold as an individual of good growth, and a measurement system and an evaluation system used for the method.

First claim

What is claimed is:

1. A method for evaluating vitality of a plant in management of roadside trees, park trees, and garden trees, and in production of agricultural plants, comprising:
measuring delayed luminescence amounts of a leaf of a plant subject to evaluation at x seconds and y seconds after excitation light irradiation, where x and y are x≠y, to obtain two data items D x1 and D x2 of delayed luminescence amount, wherein the delayed luminescence amounts are measured noninvasively, wherein x and y are 0.8 to 5 when the evaluating vitality is based on a vitality index that reflects acute stress, and x and y are 10 to 300 when the evaluating vitality is based on a vitality index that reflects chronic stress, wherein the vitality index that reflects acute stress is a sudden variation of water potential or xylem pressure potential, and wherein the vitality index that reflects chronic stress is a decrease of branch growth increment and/or trunk growth increment, and wherein the plant is selected from the group consisting of a roadside tree, a park tree, a garden tree, and an agricultural plant;
obtaining an operated value by any of the following formulae (1), (2), and (3) using D x1 and D x2 :
O=D x1 /D x2   (1)

O=D x1 −D x2   (2)

O= ( D x1 −D x2 )/( D x1 +D x2 )  (3)

wherein D x1 represents the data item of delayed luminescence amount at x seconds after excitation light irradiation, D x2 represents the data item of delayed luminescence amount at y seconds after excitation light irradiation, and O represents the operated value, wherein the data is processed by any of the following (i), (ii), and (iii):
(i) ranking the data items based on the obtained operated value or a coefficient value;
(ii) assuming a normal distribution to calculate a prediction interval corresponding to the preset upper limit threshold or the preset lower limit threshold, and classifying the data items based on the prediction interval; and
(iii) calculating, by a bootstrap method, a confidence interval of percentile value corresponding to the preset upper limit threshold or the preset lower limit threshold, and classifying the data items based on the confidence interval;

comparing the obtained operated value with a predetermined threshold;
determining a vitality state of the plant based upon the comparison of the operated value with the predetermined threshold,
wherein an individual plant having the operated value not less than a preset upper limit threshold is determined as an individual of good growth, and/or an individual plant having the operated value not more than a preset lower limit threshold is determined as an individual of poor growth, if the vitality index correlates positively with the operated value, and
wherein the individual plant having the operated value not less than the preset upper limit threshold is determined as the individual of poor growth, and/or the individual plant having the operated value not more than a preset lower limit threshold is determined as the individual of good growth, if the vitality index correlates negatively with the operated value; and
identifying and selecting the plant that is determined as an individual of good growth or poor growth.

2. The method for evaluating vitality according to claim 1 , wherein x and y are included in a time domain of 0.2 to 300 seconds after excitation light irradiation.

3. The method for evaluating vitality according to claim 1 , further comprising:
measuring a chlorophyll amount in the plant leaf to obtain chlorophyll amount data; and
calculating data of corrected delayed luminescence amount by correcting the obtained data of delayed luminescence amount by the chlorophyll amount per predetermined area;
wherein the data items of corrected delayed luminescence amount are used in place of the data items of delayed luminescence amount in the obtaining of the operated value or the coefficient value.

Assignees

• Univ Kyoto
• Hamamatsu Photonics Kk

Inventors

• Imanishi Junichi
• Katsumata Masakazu
• Kobayashi Yuko

Classifications

• G01N2021/635

  Photosynthetic material analysis, e.g. chrorophyll · CPC title

• G01N2201/0221

  Portable; cableless; compact; hand-held · CPC title

• G01N33/0098 Primary

  Plants or trees (wood G01N33/46) · CPC title

• G01N2021/6484

  Optical fibres · CPC title

• G01N21/6408

  with measurement of decay time, time resolved fluorescence · CPC title