پديد آورندگان :
غلامعلي‌پور علمداري، ابراهيم دانشگاه گنبدكاووس - دانشكده كشاورزي و منابع طبيعي - گروه توليدات گياهي، گنبدكاووس , پور نمازي، رشيد دانشگاه گنبدكاووس - دانشكده كشاورزي و منابع طبيعي - گروه توليدات گياهي، گنبدكاووس , بياباني، عباس دانشگاه گنبدكاووس - دانشكده كشاورزي و منابع طبيعي - گروه توليدات گياهي، گنبدكاووس , طليعي، فاختك دانشگاه گنبدكاووس - دانشكده كشاورزي و منابع طبيعي - گروه توليدات گياهي، گنبدكاووس
كليدواژه :
خرفه , رنگيزه كلروفيل , زيست‌سنجي , قياق , گل گندم
چكيده لاتين :
Introduction: Interference includes competition for environmental potentials and allelopathy. By releasing
chemical compounds, usually of secondary metabolites, in various ways such as root exudation, decomposition,
leaching and volatilization, allelopathic weeds may have positive, negative or even neutral effects on crops.
Therefore, the purpose of this experiment was to evaluate the hetrotoxic potential of Sorghum halepense, Portulaca
oleracea and Centurea depressa in characteristics of germination, chlorophyll content and carotenoid pigments of
cress under laboratory conditions.
Materials and methods: For bioassay experiments, various concentrations of 0, 20, 40, 60, 80 and 100% of
the weeds such as S. halepense, P. oleracea and C. depressa were prepared with the help of distilled water and
were subsequently separately applied on 50 certified seeds of cress. In this experiment, characteristics such as rate
and germination percentage, content of chlorophyll a, b, total chlorophyll content and carotenoids were measured
based on the chilled acetone method.
Results: Regression model showed that rate and germination percentage of cress significantly decreased at
concentrations higher than 80% of S.halepense only. For every unit increase in the concentration, radicle length,
seed vigor, content of total chlorophyll and carotenoids of cress decreased about 0.08 cm, 8.68, 0.007 mg/g and
0.007 mg/g, respectively. According to the results, there was an exponential relationship between different
concentrations of the P. leracea extract with germination characteristics and photosynthesis pigments of cress so
that in most cases, these characteristics up to concentration of 40% had moderate decline, but beyond this
concentration, they showed a steep decline. In case of C. depressa, rate and germination percentage, as well as the
shoot length of cress decreased about 14.67, 14.67 and 29.81% respectively, using only a concentration of 100%.
However, radicle length and seed vigor of cress decreased with increased concentrations of aqueous extract of C.
depressa. The most reductive effects were obtained in the treatment of 100%, which were about 52.38 and 55.44%
respectively. Amount of total chlorophyll of cress decreased about 14.37, 27.59 and 25.29% respectively in
concentrations of 60, 80 and 100% of C. depressa extract, as compared with the control. On the other hand,
concentrations of 20 and 40% of C. depressa had no significant effect on the pigment studied. The result of
carotenoids content was the same as total chlorophyll.
Conclusions: Based on the results, the weeds studied, especially P. oleracea, with high concentrations, had
strong hetrotoxic effect on germination characteristics and photosynthesis pigments. This requires further
investigation in a natural environment where targeted plants grow in close proximity.
