Foliar-applied KPhi alleviates UV-B stress in potato (Solanum tuberosum) independent of the UVR8 photoreceptor pathway

DALEO, GUSTAVO RAÚL; OLIVIERI, FLORENCIA PÍA; OYARBURO, NATALIA SOLEDAD; MACHINANDIARENA, MILAGROS FLORENCIA

Puerto Vallarta

Congreso; XVII National Congress on Plant Biochemistry and Molecular Biology. X Joint Mexico- U. S. Symposium; 2017

Foliar-applied KPhi alleviates UV-B stress in potato (Solanum tuberosum) independent of the UVR8 photoreceptor pathway Phosphites (Phi), inorganic salts of phosphorous acid, have been described that enhance plant defense through Induced Resistance (IR). The use of these compounds is an innovative strategy to improve the yield and quality of crops. Phi, similar to other plant inductors, are thought to be effective against different types of biotic and abiotic stress, and it is assumed that the underlying signaling pathways probably overlap and interact. Part of the signaling pathways triggered by UV-B radiation, for instance, is known to crosstalk with other signaling routes that respond at biotic stress. In contrast, UV-B-specific signaling, controlled by the receptor UVR8, is of major importance in mediating photomorphogenic acclimation responses. In our previous work, potassium phosphite (KPhi) pre-treatment prevented the oxidative stress caused by UV-B in potato. These s results suggest that KPhi-induced tolerance to UV-B could be explained by an increase of the antioxidant ability of potato leafs exposed to enhanced UV-B radiation.The aim of this work was to study the effects of foliar applied KPhi on the UVR8?mediated response to UV-B in potato plants. For this, the expression of key genes of the UVR8 specific pathway were analyzed by qPCR, in potato leaves of KPhi- pretreated plant exposed to UV-B radiation. In addition, flavonoid accumulation was also determined in these plants. Our results suggest that KPhi-mediated tolerance to UV-B stress appear to be independent to plant-specific UVR8-COP1-HY5 pathway