Effects of the Biofertilizers Vermicompost and Azotobacter on Qualitative and Quantitative Characteristics of Petunia hybrida

Petunia belongs to the genus Petunia and family Solanaceae and is a native of South America. An experiment laid out in the factorial arrangement using the completely randomized design with 2 factors and 4 replications was conducted to study the effects of Vermicompost and Azotobacter biofertilizers on qualitative and quantitative characteristics of two cultivars: Persian petunia and Petunia hybrida. The treatments were various application rates of vermicompost (12.5, 23, 37.5, and 50 g/m2) and the various rates of Azotobacter (0, 25, 50, 75, and 100 %). The variety in this experiment was Petunia hybrida. Results of ANOVA indicated the effects of Vermicompost on plant height, stem diameter, number of flowers, fresh and dry weight per plant, dry weight of aerial organs, dry weight of roots, and flower diameter, and the effects of Azotobacter on dry weight of aerial organs were significant at the 1% level. However, Vermicompost had no significant effects on number of leaves. In the Persian cultivar, the effects of Vermicompost on fresh weight per plant and number of leaves were significant at the 1% level. The mutual effects of Vermicompost and Azotobacter were not significant on any of the characteristics, and Vermicompost with 37.5 g/m2 had the maximum effect on flowering in Petunia hybrida (which was significantly greater than that of the control).