The allelopathic effects of some common weeds on paddy rice (Tarom variety) in Iran

摘要

Allelopathic effects of aqueous whole plant leachates of dominance weed (Cyperus difformis and Echinochloa crusgalli) and non dominance weed (Paspalum paspaloides and Sagittaria trifolia) on biochemical, physiological, growth and yield parameters of paddy rice (Tarom variety) of northern Iran were examined by foliar application of whole plant leachates of above said weeds. Spraying aqueous whole plants leachates (5%) showed that the content of phenols in flag leaf of treated crop was significantly increased by whole leachates of Cyperus difformis and Echinochloa crusgalli at P=0.05 by ANOVA. The content of total chlorophyll in flag leaf of test crop was significantly decreased by whole leachates of Cyperus difformis and Sagittaria trifolia. This study also showed that whole plant leachates of selected weeds did not show much inhibitory effect on growth parameters (number of total tillers per pot, plant height and elongation of flag leaf). On the contrary elongation of panicle and total filled grainper panicle was inhibited by foliar application of whole leachates of selected weeds. In case of number of effective tillers per pot, Cyperus difformis along Sagittaria trifolia significantly hampered on the number of effective tillers per pot only while 1000 grain weight and the number of grain per panicle were not affected by whole leachates of all treatments. However, whole plant leachates of Cyperus difformis and Sagitta trifolia strongly hampered on grain yield of Tarom variety as compared with control about 30.40 and 29.63 % respectively.