القابلية التنافسية لبعض أصناف الذرة البيضاء للأدغال المرافقة

الملخص EN

To investigate the competitive ability of some sorghum cultivars to weeds , a field experiment was conducted in the fall season of 2008 at the Agricultural Fields of Missan, province.

A split-plot in RCBD arrangement was used with three replications.

The main plots included weed control treatments ,weedy check, weed free, herbicide application and mechanical control treatment whereas the sub-plots treatment included sorghum cultivars namely Milo, Tabt, Hamam.

The results showed that weed competition caused significant reduction in grain yield of all cultivars by 56.85% in comparison with the weed free treatments .The plant height of sorghum plant were reduced by 29.51% , sorghum dry wight ,number of grain/ear and weight of 1000 grains were reduced by 40.13, 30.45, 47.67% respectively.

Application of atrazine and mechanical weed control treatments caused significant increases in grain yield and its components by 1.08 and 2.12 t/h ,340.23 and 148.57 grain/ear and 5.4 and 11.76 g/1000 grains respectively.

The results also showed that various sorghum cultivars response differently to different weed treatment.

Milo cultivar caused greater reduction in weed density 10.92 plant/m2 and weed dry wights 72.4g/m2, Therefore Milo cultivar gave heighest grain yield 6.03 t/h ,Bilogical yield 16.03 t/h and greater plant hight 179.32cm.Various cultivars showed greater deterances in competitive ability to weeds, cultivars caused least reduction in grain yield , grain / ear and weight of 1000 grains in weedy treatment in comparison to free weed treatment considered as greater cultivar competitive ability to weeds.

This was observed with Milo cultivar 30.21% grain yield,17.03% grain/ear and 31.64% weight of 1000 grain.

It was concluded that this cultivar have more competitive ability to associated weeds.