Plant Protection Institute, BG-2230 Kostinbrod, Bulgaria
NAKOVA, R., 2004. Correlative dependencies between the density and growth parameters of Setaria viridis (L.) Beauv. Bulg. J. Agric. Sci., 10: 195–198
Pot trials were performed in glasshouse of Plant Protection Institute, Kostinbrod during 2000, 2001. The experiments include five variants with different density of Setaria viridis (1, 2, 4, 6 and 8 plants per pot) with four replicates. The weed height, fresh weight, dry weight and leaf area were determined on 10th, 20th, 30th, 40th days after germination of the seed. The dependence between the number of Setaria viridis and growth parameters her is summarized by the coefficient of determination (r2). It was established that the main parameters determining intraspecific competitive relations in the weed are: height, fresh weight, dry weight, leaf area. The growth parameters of Setaria virisis progressively decreased as the number of weed from 2 to 8 per pot increased. Results of investigation showed that between density of the weed and growth and development her correlative negative dependencies was found. The coefficients of determination (r2) were very high during the periodof studies 10–40 days after germination in all parameters. Marke dnegative correlations are significant. Height, fresh weight, dry weight, leaf area of weed plants significatly decreased with increasing density of Setaria viridis. The density of this weed is one of factors which govern his growth, development and seed production. Intraspecific competitive relations and correlative negative dependencies between the density of Setaria viridis and her growth parameters could be useful for examining the biological control of weeds and prediction of yield loss in crop.