Abstract:
Rose, as one of the oldest flowers in cultivation and the mos
t popular of all cut flowers
throughout the world, is susceptible to several diseases. Powdery mildew and gray mold
are two of the most common diseases in the greenhouse cultivation of roses. Changes in
plant leaf temperature mainly resulting from changes
in transpiration in response to such
stresses as pathogen infection, water stress, or physiological changes can be monitored
instantly and remotely by thermographic imaging. In this research, a smart detection and
spraying system was designed and developed
to recognize rose powdery mildew and gray
mold diseases using a combination of thermal and visible images. The system consists of a
thermal camera and a visual camera both mounted on a C
-
shaped carriage. The carriage
is capable of moving along plant rows
and rotating around each rose shrub. In addition, a
site
-
specific sprayer was designed that consisted of an electrically
-
actuated pneumatic
directional valve, a pneumatically
-
actuated directional valve, a pressure regulator, a
pressure tank, a compressor,
a manual flow control valve, and a nozzle. Droplets volume
median diameter, percent of coverage, and system performance in spraying the specified
positions were evaluated.
Analysis of the pre
-
and post
-
spray thermal images showed that
such index as tempera
ture median can be successfully exploited to determine spray
coverage and uniformity.
Keywords:
Image registration, Percent of coverage, Thermal histogram, Volume median
diameter.
