Investigation of relationship between rapid canopy closure and grain yield in Wheat

In order to investigate the relationship between rapid canopy closure and grain yield in wheat and determination of traits that affect rapid canopy closure, a study was conducted using five wheat cultivars (Atrak, Tajan, Zagros, Golestan and Viniak). Laboratoral tests (Germination, seed deterioration and seedling growth tests)and field experiment using randomized complete blocks carried out at Gorgan University of Agricultural Science and Natural Resources, in 2003 – 2004. The results showed that the correlation of seed vigor (rapid, uniformity and germination percentage) with rapid canopy closure and grain yield was not significant when there was optimum plant density in field. Rapid canopy closure had significant effect on grain yield; cultivars with faster canopy closure produced more grain yield. Leaf area index and seedling dry matter at beginning of exponential growth phase and relative leaf area development rate and relative growth rate during the exponential phase, the average of individual leaf area and leaf area ratio were detected as effective traits in rapid canopy closure.