CHARACTERIZATION OF VEGETATIVE AND GRAIN FILLING PERIODS OF WINTER WHEAT BY STEPWISE REGRESSION PROCEDURE. I. VEGETATIVE PERIOD

Przulj N., and V. Momcilovic (2011): Characterization of vegetative and grain filling periods of winter wheat by stepwise regression procedure. I. Vegetative period. - Genetika, Vol 43, No. 2, 349- 359. Modeling plant growth by mathematical functions is important for understanding plant development and growth. Most of the models of dry matter accumulation in small cereals simulated the period of grain filling while small attention has been devoted to mathematical simulation of vegetative period till anthesis. The aim of this research was to determine the most appropriate polynomial non-linear regression for dry matter accumulation till anthesis in winter wheat. Pobeda, a medium early variety, was used as model genotype for this research. A 5-year field data were analyzed by the forward procedure of stepwise regression. Although the procedure requires the maximum power of the polynomial regression to be used, we suggest using a lower power since it is easier for understanding and explanation and it is taking into account literature sources and biological laws. It can be accepted that quadratic regression model appropriately fits the process of dry matter accumulation till anthesis in winter wheat.