Allometric relationship between some morpho-physiological characteristics of corn under different tillage systems and sowing dates

 Field experiments were conducted to determine the relationship between plant leaf area as the dependent variable with leaves number, leaf dry weight, and total vegetative components dry weight and plant height as the independent variables. Treatments were two tillage systems (conventional and no-tillage) as main plots, and seven sowing dates (11 May, 18 May, 25 May, 1 June, 8 June, 15 June and 22 June) as sub plots. This research was carried out at the Research Farm of Shiraz University during 2014 and 2015 growing seasons.  The interaction between sowing date and tillage system was significant. The highest leaf area, leaf number, leaf dry weight, total dry weight and plant height were obtained in earlier sowing dates (11 May, 18 May, 25-May and 1-Jun) in both tillage systems and the lowest were obtained in the latest sowing date (22 Jun) in no-tillage in both years. Using polynomial equation for determining algometric relationship between leaf area and vegetative characteristics showed a significant relationship between leaf area with leaf number (R2=0.96 and R2=0.98), leaf dry weight (R2=0.98 and R2=0.98), total vegetative components dry weight (R2=0.96 and R2=0.96) and finally plant height (R2=0.98 and R2=0.95). These allometric relationships contribute to a better understanding of plant growth and development in corn, which is necessary for optimal management of the crop and for genetic improvement.