EXPRESSION OF THE ARABIDOPSIS ABF4 GENE IN POTATO ENHANCES DROUGHT AND SALT TOLERANCE AND INCREASES TUBER YIELD

CORTELEZZI JUAN IGNACIO; MUÑIZ GARCÍA MARÍA NOELIA; FUMAGALLI MARINA; CAPIATI DANIELA

Buenos Aires

Congreso; REUNIÓN CONJUNTA DE SOCIEDADES DE BIOCIENCIAS-LIII REUNIÓN ANUAL DE LA SOCIEDAD ARGENTINA DE INVESTIGACIÓN BIOQUÍMICA Y BIOLOGÍA MOLECULAR; 2017

LIII REUNIÓN ANUAL DE LA SOCIEDAD ARGENTINA DE INVESTIGACIÓN BIOQUÍMICA Y BIOLOGÍA MOLECULAR, entre otras

ABF/AREB (ABRE-binding factor/ABA-response element bindingfactor) proteins are bZIP transcription factors (TF) that play key rolesas regulators of abscisic acid-dependent gene expression duringabiotic stress. It has been shown that StABF1, an ABF transcriptionfactor of cultivated potato, not only regulates the responses toabiotic stress, but may also act as a positive regulator of tuberization.We developed transgenic potato plants (Solanum tuberosumcv. Spunta) expressing the Arabidopsis ABF4 gene (35S::ABF4).35S::ABF4 plants exhibited an enhanced tuberization inductionin vitro, suggesting that ABF genes might be good candidates forcrop improvement. The aim of the present study was to assess theperformance of the 35S::ABF4 plants in soil, determining the tuberyield and the tolerance to drought and salt stress. 35S::ABF4 plantsshowed normal vegetative growth and exhibited an increased tuberyield (grams of tuber obtained per plant) with respect to wildtype plants under normal conditions; the number of tubers producedper plant was higher in 35S::ABF4 lines. The leaves of 35S::ABF4plants showed reduced water loss, and higher relative water content(RWC) after exposure to dehydration or 250 mM NaCl. Transgenicplants presented higher proline content than wild type plants undernormal conditions or after exposure to stress, and higher chlorophyllcontent after salt stress. 35S::ABF4 plants showed higher tuberyield under drought or salt stress. The results obtained indicate thatthe Arabidopsis ABF4 gene is a good tool to improve abiotic stress tolerance and tuber yield in potato plants.