Abstract:
In many areas of Iran, the
reproductive growth stage of sunflower is
exposed to the drought stress. Therefore, the
investigation of irrigation management in
the farm was necessary for increasing
irrigation efficiency and decreasing water
loss. The objective of the present study was
to investigate the effect of different amounts
of super absorbent polymer (A200) and
levels of drought stress on morphological
characteristics, such as: head diameter, stem
diameter, plant height, 100-seed weight,
seed yield and physiological characteristics,
such as: relative water content (RWC),
chlorophyll concentration of sunflower (cv.
Master) under farm conditions. The
experiment was carried out as a split plot
based on randomized complete block design
with three replicates. Three irrigation levels
(irrigation after 6, 10 and 14 days) and five
amounts of super absorbent polymer (0, 75,
150, 225 and 300 kg/ha) were set as main
and sub-factors, respectively. Polymer was
added at the fourteen leaf stage of sunflower
to soil in deepness of root development. At
this same stage, drought stress was applied.
Polynomial models of each traits based on
the ANOVA were fitted. The results
indicated that drought stress has decreased
significantly all the measured traits. In this
study, seed yield has shown a significant
decrease. After 6 days, irrigation has
resulted in higher yields than other irrigation
intervals. The highest seed yield was related
to 300 kg/ha polymer application and the
lowest one was related to irrigation after 14
days with no application of polymer.
Regarding the limitation of water resources,
super absorbent polymer could be a useful
strategy for the sustainability of yield under
drought stress in sunflower.
