مقارنة بعض المبيدات الانتقائية للأدغال في حقول حنطة الخبز

الملخص EN

Field experiment was conducted wilh three replicates according to RCBD at the experimental field of Dept.

of Field Crop Sciences College of Agriculture University of Baghdad during the season 2009 2008 to compare the efficiency of the selectivety for the herbicides pendimethalin , Pyroxsulam , Chevalier and Harmony extra to control weeds and their consequence effects on grain yield and yield components of wheat .

Pendimethalin was sprayed as pre emergence at rate of 1.6 L / ha , whereas herbicicdes Pyroxsulam , Chevalier and Harmony extra were sprayed as post emergence at 0.3 L / ha , 0.3 kg / ha and 25 gm / ha respectively .

Results showed that all herbicides were significantly efficienct in studied characteristics compared to check treatmeant .

A Significant reduction in weed dry weight was observed with all herbicides treatmeants as compared to check treatmeant .

A posative effects were recorded for yield and yield components .

However the use of Pendimethalin as pre emergence treatmeant caused high reduction of weed dry weight ( 0.5 g / m2 ) and at the same time a significant increases were obtained in number of spikes , number of grain / spike , weight of 1000 grain and wheat yield reached 446.6 spike / m2 , 46.6 seed , 41.7 g and 6.9 t / ha respectively .

Pyroxsulam , Chevalier and Harmony extra gave weed dry weight ranged from 2.5 to 12.4 g , number of spikes 433.5 to 445.5 spikes / m2 , number of grain / spike 42.0 to 45.9 seed , weight of 1000 grain 39.5 to 43.8 g and grain yield 5.8 to 5.9 t / ha compared to 116.0 g , 289.1 spike / m2 , 37.0 seed , 37.0 g and 4.3 t / ha respectively in weedy treatmeant .

Therefore it can be concluded that the application of Pendimethalin as pre emergence treatmeant was the most efficient herbicide in term of weed control and the positive consequences on grain yield and yield components of wheat compard with other treatmeants .