Crosstalk between SA-mediated and ABA-mediated signaling pathways in tomato plants.    
M. KUSAJIMA (1), Y. Okumura (1), H. Nakashita (1) (1) Fukui Prefectural University, Japan

Systemic acquired resistance (SAR), one of plant defense systems, is induced by pathogen infection through salicylic acid (SA) accumulation.  The SA-mediated signaling pathway for SAR development has an antagonistic interaction with ABA-mediated signaling pathway for environmental stress responses, which was clarified in Arbidopsis, tobacco and rice. However, this mechanism have not been clarifed in many crops.   It is reported that ABA-deficient tomato mutant is more resistant against Botrytis cinerea and the suppressive effect of ABA treatment on disease resitance in tomato is not so clear.  To clarify the crosstalk between SA- and ABA-mediated signaling pathways in tomato (Solanum lycopersicum cv. Momotaro), we anlyzed SA-meditaed signaling pathway for SAR by using ABA and ABA biosynthesis inhibitor.  SAR was induced by treatment with plant activator  1,2-benzisothiazole-3(2H)-one1,1-dioxide (BIT) and benzo(1,2,3)thiadiazole-7-carbothioic acid S-methyle ester (BTH) and was estimated by the diseae resistance asssay using Pseudomoans syringae pv. tomato.  Disease resistance assay, gene expreesion analysis, and horomal biosynthesis, indicated that SAR was suppressed by ABA also in tomato.  

Abstract Number: P18-678
Session Type: Poster