What percentage of saturation is considered optimal for the survival of pathogens in soil?

The optimal percentage of soil saturation for the survival of pathogens is indeed in the range of 30% to 45%. This is because pathogens require a certain moisture level to remain viable and to facilitate their movement in soil. At this saturation range, sufficient moisture helps to support microbial activity and nutrient transport, which are crucial for pathogens.

Soils that are too dry may not provide the needed moisture for survival, as pathogens become less active or may die off. Conversely, soils that are overly saturated (approaching the higher end of the saturation range) may create anaerobic conditions, which can inhibit the survival of many aerobic pathogens and could lead to increased competition from other microorganisms. Therefore, maintaining the soil moisture in the 30% to 45% saturation range supports a favorable environment for the survival and potential growth of pathogens.