growth analysis of two cultivars of lentil using regression modeling

growth analysis is a valuable method in the study of quantitative of growth, development and crop production. in order to study the physiological growth indices of lentil plant under dry- farming conditions, an experiment was carried out as a randomized complete block design with three replications at the agricultural research station of lorestan university during 2010. in this experiment two cultivars were used including gachsaran and philip, that are appropriate and commonly in the area cultivating. in order to have more accurate study, growing degree day (gdd) index was used for fitting growth curves, and then appropriate model was selected for each growth index using non-linear regression models. the results of the growth indices showed that gachsaran cultivar has higher priority than philip cultivar in leaf area index, but philip cultivar had higher priority than gachsaran cultivar in crop growth rate, net assimilation rate and dry matter production. relative growth rate was similar in both cultivars. in total, growth characteristics of gachsaran cultivar leading to higher seed yield and growth characteristics of philip variety leading to produce more biological yield.