Effect of carbohydrates on the growth of bacteria in liquid culture
Due to the raw data sets naturally fit a non normal model (Figure1 & Figure 4), it is necessary to remove the outliers (values greater than 0.75) and do log transformation. After transformation, the distribution of data set is nearly normal (Figure2 & Figure5). The boxplot present the correlations among optical density and carbohydrates, plant growth promoting rhizobacteria, time (Figure3).
Growth of bacteria in soil amended with different carbohydrates:
After the transformation, the data set is nearly normal (Figure5), the boxplots show the correlation between the transformed data
(population of bacteria) and different carbohydrates, plant growth promoting rhizobacteria (Figure 6). At the same time, the correlation coefficient is 0.38 between the incubation time and the population of PGPRs, while the correlation coefficient is 0.16 between the concentration of carbohydrates and the population of PGPRs (Figure7).