The synergistic benefits of β-aminobutyric acid and γ-aminobutyrate on salt and drought tolerance in cassava

beta-Aminobutyric acid (BABA) and gamma-aminobutyrate (GABA) had a positive role in alleviating the damage when plants were exposed to abiotic and biotic stresses. However, it is not known whether exogenous of GABA and BABA could improve the tolerance of cassava plants, and their synergistic benefits. In the current study, we found that the cassava seedling improved the tolerance by exogenous of BABA and GABA under salt and drought stress condition, as reflected by reducing the accumulation of hydrogen peroxide and increasing the activities of antioxidant enzymes. Meanwhile, the expression of genes encoding antioxidant enzymes was significantly unregulated by salt or drought stress after application of BABA and GABA, separately. Moreover, the transcript levels of DREB2A and SOS2 were significantly unregulated by salt after application of BABA and GABA, separately, and expression of DREB2A, NCED3, and CBF3 was significantly unregulated by drought stress after application of BABA and GABA, separately. Interestingly, there was a synergistic benefit on improving the plant stress tolerance by combining the application of BABA and GABA. Therefore, our study provides new insights into maintaining the high yield by combining use of the chemical compounds in cassava which is relatively hard to be genetically modified.