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In order to determine the effects of plant density (30, 45, 60 plant perm) on physiological characteristics of common bean (Talash, Shaad and
Daneshjoo), two sets of experiments were conducted in the Karaj Agricultural
Research Station of Tehran University during 1993-1994. A split plot design
with 4 replications was used. Cultivars were considered as main plots and randomized in complete blocks. Densities were considered as sub plots and
randomized in each main plot. Planting date was 11th and 12th May in 1993 and 1994, respectively. Samples for evaluation the growth indexes were
obtained weekly and also data were collected for determining grain yield and biological yield at maturity stage in every year. Grain yield was calculated in
hectar according to 13 percent of humidity. The number of abnormal seeds were counted in samples that obtained in 1994 and determined their
percentages. The number of sub branches, pods, seeds per pod and 100-seeds weight were obtained in every sample consists of twenty plants in every plot.
DM, CGR and RGR parameters were estimated according to regression method. Variablities of CGR and RGR were illustrated by graphs according to
estimated data during the growth season. Statistical analysis showed that there were no significat differences among cultivars for grain and biological yield.
However, when the density increased, average grain and biological yield increased. According to the obtained results, the effect of year was only
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significant on 1 DO-seeds weight. Generally, there were no significant differences in grain yield among Talash, Shaad and Daneshjoo varieties in
Karaj. Maximum CGR during the growing season is also proposed as suitable
physiological index.