Abstract:
Water stress is known as the
major threat to reduced growth and yield of
plants in arid and semi-arid regions.
Potassium is one of the indicators of plant
responses to water stress. To evaluate the
impact of water stress and levels of
potassium on yield and yield components of
two varieties of mung bean (Vigna radiata)
(promising lines VC6172 and Indian), an
experiment in the form of split factorial,
based on randomized complete block design
with three replicates was conducted in 2011,
at the research farm of Safi-Abad Dezfool,
Iran (latitude 32016’ N, longitude 48026’ E
and altitude 82.9 m above sea level) .Water
stress in three levels: irrigation at 120 (no
stress), 180 (moderate stress) and 240
(severe stress) mm evaporation from pan,
were allocated to the main plots and
potassium fertilizer at three levels (0, 90,
180 kg /ha) and two varieties of mung bean
(promising line VC6172 and Indian) were
allotted to the sub-plots. Results showed
that water stress and potassium fertilizer
significantly affect all traits. The highest
grain yield (2093 kg /ha) was obtained from
no stress treatment in the case of 180 kg /ha
potassium. Total dry matter, number of pods
and grain yield, were significantly different
between the two varieties. The interaction
between fertilizer and variety, on dry matter
and grain yield and the interaction between
irrigation and variety, on dry matter were
significant. We conclude that use of
potassium fertilizer can reduce the adverse
effects of water stress.