A novel ABA structural analogues enhanced plant resistance by inducing the plant immunity and inactivating ABA signaling pathway

Abscisic acid(ABA)is a phytohormone that not only important for plant growth,but also mediating the stress response.The roles of ABA in plant immunity are especially multifaceted.Recently,the ABA functional analogues are of great significance to promote its application.Here,we reported an ABA functional analogue named 167A.167A inhibits plant growth and seeds germinating of Arabidopsis.Meanwhile,the 167A enhanced the plant immunity,which is opposite of ABA.We further investigated the PTI-response after 167A treatment,and the results show that the ROS burst,callose deposition accumulate with 167A treatment.Moreover,167A also influence the degree of stomal closed.RNA-seq assays show that the 167A down-regulated the ABA associated genes and upregulated the JA/SA/ET associated genes.Through genetic analysis,the 167A modulating the plant resistance through the PYR/PYL Receptors.Together,these results demonstrate that a novel ABA analogue 167A positive regulated plant immunity and has great potential for agricultural applications.

Multiple forms of vitamin B_(6) regulate salt tolerance by balancing ROS and abscisic acid levels in maize root

Salt stress causes osmotic stress,ion toxicity and oxidative stress,inducing the accumulation of abscisic acid(ABA)and excessive reactive oxygen species(ROS)production,which further damage cell structure and inhibit the development of roots in plants.Previous study showed that vitamin B_(6)(VB_(6))plays a role in plant responses to salt stress,however,the regulatory relationship between ROS,VB_(6) and ABA under salt stress remains unclear yet in plants.In our study,we found that salt stress-induced ABA accumulation requires ROS production,in addition,salt stress also promoted VB_(6)(including pyridoxamine(PM),pyridoxal(PL),pyridoxine(PN),and pyridoxal 5′-phosphate(PLP))accumulation,which involved in ROS scavenging and ABA biosynthesis.Furthermore,VB_(6)-deficient maize mutant small kernel2(smk2)heterozygous is more susceptible to salt stress,and which failed to scavenge excessive ROS effectively or induce ABA accumulation in maize root under salt stress,interestingly,which can be restored by exogenous PN and PLP,respec-tively.According to these results,we proposed that PN and PLP play an essential role in balancing ROS and ABA levels under salt stress,respectively,it laid a foundation for VB_(6) to be better applied in crop salt resistance than ABA.