Predicting Seedling Emergence of Different Wild Oat (Avena ludoviciana)

Wild oat is an economically important annual weed throughout small grains production areas. Timely and more accurate control of wild oat may be developed if there is a better understanding of its emergence patterns. Six wild oat populations, collected from different climate regions, were sown in agricultural reaserch field of University of Tehran located at Karaj, Iran during 2012-2013 growing season. The experimental design was a randomized complete blocks with factorial arrangement of treatments in three replications. Wild oat populations were collected from Ahvaz, Karaj, Kamyaran, Ghazvin, Shiraz and Isfahan. Seedling emergence pattern was surveyed under rain fed and irrigated conditions. Rusults indicated that seedlings emergence were started in 306 growing degrees day (GDD) Less GDD was needed for irrigated (461-482) compared with rain fed conditions (546-665 GDD) to reach 50% emergence. There was no difference of GDD to reach 50% emergence, in Ghazvin and Ahvaz populations under the two moisture conditions. Among wild oat populations, Ahvaz needed maximum growing degree days to reach 50% emergence, receiving 784 and 755 GDD under rainfed and irrigated conditions, respectively. Overall, the results showed that wild oat emergence could be predicted based on growing degree days from soil temperature. This approach can help to provide appropriate time of wild oat control.