Force-A Multiplex Operating instructions
Multiplex use
During measurements, you can
display these 4 usual signal/indices
on the touch screen :
Check Multiplex every day you measure with
the blue (and red for Mx 330) standard : use
the sheet ‘Multiplex checking’.
You must avoid saturation in single signals.
FRF_R, FRF_G, FRF_B, FRF_UV must not :
- exceed 4300
- be under 20
You have to adapt the « measurement range » to:
1/ diameter of the aperture of Multiplex.
2/ level of chlorophyll of the plant you are measuring
3/ in field or in greenhouse measurements
For more explanations, see MxUserGuide_Firmware.pptx.
Slide 6 : Cfg screen.
Mx 330: use black
glove to measure
Multiplex readings in fields
For both measurement mode (one shot and continuous), 3 principles to respect:
- measure leaves with the same physiological age
- try to be as close as possible to the leaves
- try to cover as much as possible the aperture of the Mx with leaves
Multiplex readings on fruits
To be sure of the quality of the signals, use the measurement
area well adapted to the plant you measure : 4 / 6 or 8 cm
aperture diameter.
NOOK
You must always keep the same distance from the fruit.
The good distance is : the fruit against the Multiplex.
OK NO
Be careful with the pedicel
of a fruit.
It is rich in chlorophyll, it
influences the reading.
Multiplex Use
OK
You can use Mx whatever the weather,
except under rain.
You must not measure with the
Multiplex turned towards the sun.
NO NO
NO
Avoid fluorescent light if you
measure in the laboratory.
Multiplex Use
Other things to check regularly :
- Wash the measurement area and the plastic protection upon optics with
alcohol or water as soon as these parts are dirty.
- Look at FRF_R during measurement. Be sure it is < 4300 and > 20.
- Compile measurements in the air and on the blue standard every day in a
dedicated file.
- Try to do the same plot at the same time every day, in case of measurement
of kinetics.
- User effect is possible. Try to always dedicate one Mx to the same user.
- Don’t exceed 100 files on the SD card. Transfer and delete files regularly .
- Use the 512 Mo SD card provided with the Multiplex.
Multiplex®firmware
Main screen
7
Del.
Cfg >
10:15
press
button
to measure
alt p s 1 0
1 AH
When you switch on the Multiplex, this screen is displayed.
Measurement can be performed by pressing one of the two trigger buttons on the handle.
Main screen
8
Del.
Cfg >
10:15
FRF_R ANTH_RG
SFR_R FLAV
0.2568
2.675
1523 0.2156
alt p s 1 1
1 AH
Access to « alt
screen »: to come
back on previous ‘p’
‘s’ or ‘file name’
Access to « Cfg
screen »: to settle
different settings
Access to « Del
screen »: to delete
last reading
=> 4 levels to classify your measurements
.csv file column: population sample reading .csv file name
Battery level Time
One signal with its value.
You can display all the signals saved by Multiplex, if you press
successively here.
When GPS is on, this
symbol is displayed.
‘population’ / ‘sample’ / ‘file name’ are long press buttons (2 sec) :
you can increment the rank by pressing the respective buttons.
Main screen
9
A file name is YYMMDDXX.csv, defined as :
- YY : year
- MM : month
- DD : day
- XX : two letters which correspond to the file name
(bottom-right edge of the main screen)
A new file is created each time you :
- switch on the Multiplex,
- press the file name button,
When a new file is created :
- there are incrementation of the 2nd letter of the file name
-‘p’ and ‘s’ rank are back to 1
-‘reading’ rank is back to 0.
The reading rank in each file is not limited.
Save regularly the files on a computer and delete them from the SD card.
All datas are saved on the sd card, into a .csv file.
Cfg screen
10
<--
GPS
Mode 1 Ext.
Int.
main -->
Off Internal GPS
(antenna provided
with Multiplex) : You
have to connect it
on Mx if you want to
use the GPS mode.
External GPS : if
you want to use
your own GPS
Another screen allow
you to set the Baud
rate (4800, 9600,…)
On / Off : Display if
the GPS is on or
off.
Mode 1 : To switch on GPS, press this button and wait few seconds (only outdoors).
For each measurement, GPS datas are saved on .csv file.
Mode 2 : it appears when ‘measurement mode’ is ‘contin.’
In this mode, only 2 GPS coordonnates are saved, at the beginning and
the end of the continuous measurement
Acquisition speed of ‘continuous’ mode : Mode 1 = 2 Hz / Mode 2 = 20 Hz.
Mode 2
If the GPS is connected, the
date and time are updated.
Cfg screen
11
<--
Measurement mode
contin. USB
SD - card
main -->
One shot
One shot mode
(250 flashes per reading)
Continuous mode
(acquisition speed : 20 Hz)
Datas saved on
the sd card
Datas saved on a
PC with a USB
cable
Continuous mode : only raw single signals are saved in the file (to allow the acquisition speed = 20 Hz).
Indices need to be calculated separately.
You can use the file MxContinuousMode_Formula.xlsx to get the formulas directly.
Cfg screen
<--
Measurement range
Cfg 1 Cfg 2
main -->
Cfg 3
3 ‘measurement range’ depending on the power in LEDs: Cfg 1 < Cfg 2 < Cfg 3.
(Cfg 4 can appear for a few customers : usually Cfg 2 < Cfg 4 < Cfg 3)
The aim of these 3 ‘measurement range’ is to get enough fluorescence, but not too much.
FRF_R, FRF_G, FRF_B, FRF_UV (when UV LEDs present) must not exceed 4300 and be under 20.
You have to adapt the ‘measurement range’ to:
1/ diameter of the aperture of Multiplex.
2/ level of chlorophyll of the plant you are measuring
3/ in field or in greenhouse measurements
4/ motionless or in movement measurement
Usually, for the aperture diameter 6 / 8 cm, motionless :
Cfg 1 : plant in greenhouse
Cfg 2 : leaves, fruit unripe outdoors.
Cfg 3 : mature fruit with low level of chlorophyll
Usually, for the aperture diameter 4 cm, motionless :
Cfg 2 : plant in greenhouse
Cfg 3 : leaves, fruits
Cfg screen
13
<--
Settings
Factory
main -->
OK
4 signals On
Time zone + 2
Off
-
Reboot the firmware with factory settings.
Display one or
four signals on
the touch screen
Adjust time with your local time
(use this button if you don’t use the GPS)
One-signal-displayed mode speeds up a little bit measurements compared to the four-
signals-displayed mode.
Alt screen
16
Pop Sam file
10:15
FRF_R
SFR_
2.675
1523
alt
1
+
-
2
+
-
AH
+
-
Alt : To continue measurements on a previous file / sample / population.
You just have to adjust with ‘+’ or ‘–’ the level of classification you want to pursue.
Alt screen is very useful if you have to switch off the device (lunch time,…) during a
measurement session.
Measurement rank can not be changed.
Multiplex readings on leaves.
17
1 2 3 4
Leave Face
Plane Tree Ad
Plane Tree Ab
Hazel Ad
Hazel Ab
SFR_R FLAV ANTH_RG
2,11 0,40 -0,04
1,13 -0,05 -0,01
2,34 0,46 -0,01
0,97 -0,17 0,11
1
2
3
4
The Multiplex measurement area allow to integrate the leaf heterogeneity.
SFR_R: Chlorophyll index. Values are different between adaxial and abaxial side because chlorophyll content is higher in
adaxial side (palisade parenchyma) than in abaxial side (spongy parenchyma)
FLAV: Flavonols index. Values are higher in adaxial side compared to abaxial side (UV light induce flavonols).
Like here, FLAV can be < 0. FLAV = log (FRF_R / FRF_UV), when there is few flavonol in the leaf, FRF_UV > FRF_R.
ANTH_RG: Anthocyanins index (for red leaves, like in picture 4).
In the absence of anthocyanins, ANTH_RG is inversely correlated to chlorophyll content.
Index range values :
SFR_R : 0 to 3.
FLAV : - 0,5 to 2,5.
ANTH_RG : -0,2 to 1,5.
Values are relative values. They can’t be completely compared between species.
Multiplex always displays a value, whatever the support (air, table,…), and even if there is no chlorophyll, polyphenols,…
Multiplex can’t measure on liquid (the way to measure need to respect the scheme : epiderm / mesophyll).
18
A few examples of index values for apples.
We can see differences between :
- Cultivars
- Readings on sun-exposed or shaded side
Multiplex readings on fruits.
SFR_R, ANTH and FLAV are corrected by
the value of blue standard foil reference.
Multiplex NBI. Turf.
19
Pisa University. 2010.
6 treatments : 0 / 50 / 100 / 150 / 200 / 250
kg N / Ha. 28th of june.
4 replicates (1 * 1 m) per treatment.
Mx measurement. 12th of July.
Leaf N content.
Agati et al. EJA . 2013.
NBI®
NBI®= CHL / FLAV
20
1
2
3
4
5
6 7
Leaves heterogeneity on maïze.
Leaf per leaf.
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