Soil bacterial community is associated with high potato production and minimal water use

In agriculture, water
consumption for crop production represents 69% of all water use. Precision
irrigation systems based on available soil water have been developed to improve
crop production, reducing water use. Besides the improvements in irrigation
management, a better resolution of the optimal water level is required, and
revealing the impact of soil matric potential on the soil microbial community
may help. Here, the effect of four soil matric potential treatments (-15 kPa, -25
kPa, -30 kPa, and -45 kPa) was evaluated on the soil microbial community across
three potato cultivars and two soil types (silt and sand). The results
confirmed the soil matric potential with -25 kPa as the optimal irrigation
level, which promoted high potato production using the minimal water use. The
irrigation levels affected the composition, predicted functionality, and ecological
network of soil bacterial community. Water excess (-15 kPa) and deficit (-30
kPa, and -45 kPa) promoted an increase in microbial interaction and
alpha-diversity. The results suggested higher Positive/Negative ratio for phyla
Proteobacteria, Actinobacteria, and
Acidobacteria in optimal irrigation level (-25 kPa)
than other irrigation levels. Also, correlation analyses revealed an
interesting association between the irrigation levels, potato production, and
bacterial functionality, especially in carbon cycle (fixation and emission).
Therefore, this study proposed important associations between the soil
bacterial community and water management, focusing on high potato production
and minimal water use. The advancement of this knowledge may lead to a more
comprehensive assessment of the optimal irrigation levels of others crop
production systems. Furthermore, the
inclusion of biological mechanisms, especially microbial interactions, in
agriculture studies has the potential to contribute to the development of water
management practices conducive to both increasing crop yield and maintaining a
sustainable soil environment.