اثر تراكم و دوره هاي مختلف تداخل سورگوم بر فيلوكرون و سرعت ظهور برگ ذرت

Effects of Sorghum Densities and Interference Periods on Maize Phyllochron and Leaf Appearance Rate

In order to investigate the effects of sorghum densities and interference periods on maize phyllochron and leaf appearance rate, a factorial experiment based on randomized complete block design with three replications was conducted in 2002 at the Research Field of the Faculty of Agriculture, University of Tabriz, Iran. Factors were: sorghum plant densities (4, 8, 12 plants/m2) and interferences periods (0, 14, 28, 42 days after maize seedling emergence and also during plant life cycle). Optimum maize density was 7.8 plants/m-2. The results showed that the phyllochron and the time between appearance of successive leaves on a shoot was minimum in maize monoculture. With increased sorghum density and interference, the phyllochron increased, but rate of leaf appearance decreased. The vegetative growth period of maize significantly influenced by sorghum densities and interferences. The highest vegetative growth period of maize was obtained at maximum density and interference of sorghum, and the lowest vegetative growth period obtained in maize monoculture. .