It may not be advisable to directly compare the growth of organisms on each plate to each other for several reasons:
Variability in conditions: Each plate may have different conditions that affect organism growth, such as variations in temperature, pH, nutrient availability, or exposure to antibiotics. These differences can lead to growth rate variations, making direct comparisons unreliable.
Different organisms, different growth requirements: Organisms have diverse growth requirements, and comparing their growth directly may not provide meaningful insights. Some organisms may require specific nutrients or environmental conditions not present in all plates. Comparing growth between organisms with distinct growth requirements can lead to inaccurate conclusions.
Interference and competition: Some organisms interact with each other on the plate, through cooperation or competition. This can impact their growth rates and make direct comparisons challenging. For example, one organism may inhibit another's growth, resulting in apparent differences in growth rates that are not reflective of their individual capacities.
Statistical considerations: To draw reliable conclusions, consider data analyses when comparing growth. Simply observing growth visually may not provide a comprehensive understanding of the data. Statistical tests can help determine if observed differences are significant or simply due to random chance.
Instead of comparing growth directly between plates, it is often more advisable to analyze growth patterns within each plate individually. This allows for a better understanding of the specific conditions and interactions on each plate. This can provide valuable insights into individual organism growth characteristics.