Skip to main content

Relationship Between Foliage Temperature and Water Stress in Potatoes

Stark, J.C. and Wright, J.L. (1985) Relationship Between Foliage Temperature and Water Stress in Potatoes. American Potato Journal. 62:57-68.

[img] PDF

Download (595kB)


Field studies were conducted in southern Idaho to evaluate the
possibility of using thermal infrared measurements of potato foliage to
detect soil water deficits. Concurrent measurements of foliage-air temperature
differences (Tf-Ta), leaf water potential (Ψleaf) and vapor pressure
deficit (VPD) were obtained from differentially-irrigated Russet Burbank
and Kennebec potatoes during the 1982 and 1983 growing seasons. Foliage-air
temperature differences for well-watered potatoes were linearly related
to VPD. Differences in Tf-Ta values between stressed and well-watered
potatoes were relatively small in the early morning when evaporative demand
was low. However, severe soil water deficits caused afternoon Tf-Ta
values to rise as much as 8.0 C above non-stressed levels under conditions of
high VPD.

Foliage-air temperature differences and VPD data were used to construct
a plant water stress index (PWSI) which reflected the rise in Tf-Ta,
above non-stressed levels at a given VPD. The PWSI was linearly related to
depressions in Ψleaf caused by moderate to severe soil water deficits.
However, the PWSI did not increase significantly above non-stressed values
unless the soil matric potential Ψsoil fell below – 70 kPa (centibars). Since
potatoes are normally irrigated before Ψsoil falls below – 60 kPa, it appears
that foliage temperature measurements cannot be used to effectively
schedule irrigation for this crop.

Item Type: Article
NWISRL Publication Number: 0538
Subjects: Irrigated crops > Potato
Mass Import - autoclassified (may be erroneous)
Depositing User: Dan Stieneke
Date Deposited: 20 Nov 2010 21:52
Last Modified: 13 Jan 2017 23:04
Item ID: 427