چكيده لاتين :
Introduction: Strangle wort (Cynanchum acutum) is a perennial weed that could be propagated by seeds
and vegetative organs. This brings about harvesting problems for some crops such as cotton, sugar beet,
wheat and maize. In recent years, this weed has caused huge losses in sugar cane fields. The role of
environmental conditions in weed management is highly important. Given this, the present study seeks to
investigate the effects of environmental conditions (salinity and drought stress) on germination characteristics
of strangle wort weed.
Materials and Methods: In order to investe the effect of different salinity and drought levels on strangle
wort (Cynanchum acutum), two seperate experiments were conducted at Hakim Farabi Khuzestan Sugar
Cane Research Institute in 2014-2015. The experimental design was completely randomized, with four
replications. The treatments were different salinity levels at 8 levels (0, 2.5, 4.5, 6.5, 8.5, 12.5, 16.5 and
20.5ds/m) and the second experiment involved different drought stresses (osmotic potential) at 7 levels (0, -1,
-3, -6, -9, -12 and -15 bar).
Results: The results of salinity stress experiment showed that with increases in salinity levels from 0 to
20.5 ds/m, germination, radicle length, plumule length and seedling weight decreased by 61, 80, 91 and 99%,
respectively. The results of drought stress experiment showed that with increases in salinity levels from 0 to -
15 bar, all studied traits, i.e., germination, radicle length, plumule length and seedling weight all decreased by
100%.
The analysis of variance results showed that in all the traits, there were significant differences between
salinity and drought stress in 1% probability level. In this research, in the salinity experiment, in most of
traits, especially radicle length quickly decreased after 8.5 ds/m salinity to higher levels and in drought stress
experiment, after -3 bar to higher levels.
Conclusion: On the whole, it seems that sufficient information about this weed is vital for the adoption of
the best control method, and gaining insights into how strangle wort responds to environmental stress,
especially salinity stress, could help us to come up with new control approaches for this invasive weed. This
can present a proper ecological approach that could be adopted in sustainable agriculture programs, which is
environmentally sound as it decreases the use of chemical inputs. In addition, in order to lower the tolerance
of this weed to salinity and especially drought stress, it is suggested that it be used for weed management
programs. According to the results of this study, soil salinity higher than 8.5 ds/m and drought tension above
than -3 bar can cause sizeable reduction in most traits (growth parameters) especially in root length. In most
of the traits scrutinized, the tolerance of the weed to salinity and drought stress was 12.5 ds/m and -6 bar,
respectively.
