EVALUATION OF IRANIAN CULTIVARS OF BREAD WHEAT (TRITICUM AESTIVUM L.) FOR COMPETITIVE ABILITY AGAINST RYE (SECALE CEREALE)

Rye is one of the troublesome weeds of wheat in Iran. To study the competitive ability of Iranian bread wheat cultivars agains rye, an experiment was conducted using factorial experiment based on randomized complete block design with four replications in Varamin and with three replications in Meshkindasht during 2002-2003 growin season. Treatments included eight Iranian winter wheat cultivars (Azadi, Mahdavi, Roshan, Tabasi, Pishtaz, Shiraz, Karaj2 and Nicknejad) with to levels of rye (with and without rye). Results indicated that Mahdavi cultivar had the most competitive ability againt rye with lowest percent of garin yield loss (7.32%) in presence of rye, highest grain yield (6.12 tha-1) and highest competitive index (2.16). Karaj 2 with the highest percent of garin yield loss (46.96%) in presence of rye, lowest grain yield (2.6 tha-1) and lowest competitive index (0.35) was the least competitive cultivar. Rye produced the highest and lowest number of spikes in presence of Mahdavi and Karaj 2 cultivars, respectively. Based on these results Mahdavi cultivar can be recommended for control of rye in a IWM program .