ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] By salicylic acid (SA). Belongs to the protein kinase superfamily. Ser/Thr protein kinase family. CRK subfamily. Possesses one additional DUF26 domain, as compared to other members of the CRK subfamily.