اثر دوره هاي مختلف تداخل علف هاي هرز بر شاخص سطح برگ، عملكرد و اجزاي عملكرد هيبريدهاي ذرت دانه اي

The Effect of Different Interference Periods of Weeds on, Leaf Area Index, Yield and Yield Components of Corn Hybrid

Different interference periods of weed on leaf area index, yield and yield components of corn hybrids were investigated in a factorial experiment conducted of Research Station of Faculty of Agriculture, Islamic Azad University, Tabriz Brach, based on randomized complete block design in three replicates in 2007. The treatments consisted of weed interference periods (interference at 2 - 4 leaf Stage, 4-6 leaf, 6 -8 leaf stages, full season weed interference and weed free control plot) and three corn hybrids (504, 604 and 704). Results showed that the traits such as biological yield, leaf area index and number of grain per plant in a row were affected by weed interference treatments and maize hybrids significantly. While the grain yield, and harvest index were influenced by corn hybrids, significantly. But there was not significant difference in weed interference treatments. Biological yield and leaf area index in full season weed interference in comparison with weed free control plot reduced by 25%, 48%, respectively. In this study 504 hybrid with grain yield 5.8 tha"1, biological yield 11.6 t.ha"1 and harvest index 49% was found to be better than hybrids 604 and 704 hybrids.