Activation dynamics and assembly of root zone soil bacterial communities in response to stress-associated phytohormones

We evaluated the dormancy resuscitation dynamics of rhizosphere soil associated with common bean and switchgrass in response to stress-associated phytohormones. We conducted a 2-week laboratory incubation study using soil mesocosms wherein we induced soil dormancy and then treated soils with abscisic acid and salicylic acid to assess reactivation of microbial members. We also set up relevant control mesocosms with methanol and water. We sequenced the active bacterial community by targeting both 16SrRNA and 16SrRNA gene and obtained RNA:DNA ratios to designate active taxa. Resuscitation was assessed by screening taxa that were active in the immediate aftermath of exposure to stress signals (within 24 hrs) as well as over 7 and 14 days. Taxa that move from dormancy to resuscitated state, post stress-associated phytohormone exposure, can reveal important functions of dormant microbial communities and their role in soil management and plant resilience in response to stress.