Production of IAA-like compounds is common in Bacillus strains
and this bacterial trait may improve root growth during the early
plant growth stage. In addition, stomatal closure and transpiration
reduction in response to water deficiency in plants may be induced
by auxins. The participation of bacterial auxins in the responses to
water stress was also observed by Havlova et al. (2008). Drought
significantly increased IAA production in B. megaterium, as
previously reported by Dobra et al. (2010), corroborating that
IAA also plays an important role in the stress responses. In fact, this
bacterium decreases stomatal conductance in L. dentata (with
fermented agrowaste) and in S. officinalis (with and without
fermented agrowaste).