Measuring phosphorus deficiency in plants can provide an accurate
picture for adjusting fertilization administration for maximum yields.
Traditional methods for estimating the available phosphorus for
growing crops include soil sampling or in-season plant sampling
which are costly and labor intensive. Measuring phosphorus with a
field spectroradiometer is faster, easier, more cost-effective and non-
Plants that exhibit phosphorus deficiency show purple discoloration
in the leaf margins due to increased anthocyanin production.
Prediction of plant phosphorus is possible by noting increased
reflectance at 440 and 445nm a result of increased anthocyanin which
absorbs in the green region of the VIS and reflects in the blue or red
region of the spectrum. Additional wavelength features to identify
phosphorus occur in the NIR at 730 and 930nm.
The PSR+ field spectroradiometer is lightweight, rugged and reliable
and runs on lithium ion batteries for a full day in the field. Spectra
can be collected with a direct attached lens or handheld pistol grip
with FOV lens. For single leaf measurements our unique leaf clip
utilizes a light source that is rail mounted to the instrument to keep
the heat away from damaging your samples. This allows researchers
to measure the exact same leaf all season long. The leaf clip with its
built-in white reference and trigger makes single handed
measurements very easy. The PSR+ can also be ordered with our six
inch Integration Sphere for leaf and needle measurements.
The PSR+ delivers the highest resolution and sensitivity available in
a field spectroradiometer across the full 350—2500nm spectral range.
In addition to phosphorus, the PSR+ can identify total nitrogen and
potassium—all from a single sample and its spectra.
The PSR+ runs under our DARWin SP Data Acquisition software with
immediate access to 19 vegetation indices. All data is saved as ASCII
files for use with other analysis software such as R2,chemometrics,
and statistical analysis programs. It is also available with the EZ-ID
sample identification software. EZ-ID compares a target sample
against a library of known samples. In addition, EZ-ID has a Custom
Library Builder module that allows you to build your own crop library
for use in the field.
Every Spectral Evolution instrument
includes DARWin SP Data
Acquisition software. Scans can be
compared using multiple scans in a
Measuring phosphorus in vegetation
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Tel: 978 687-1833 ◊ Fax: 978 945-0372
Copyright © 2012 Spectral Evolution, Inc
The leaf clip includes a built-in white reference and is designed to keep the heat from the illumination away
from your sample so that measurements can be accurate and non-destructive.
PSR+ works with our unique leaf clip for vegetation research in the field.