Transgenic plants expressing type 2C protein phosphatase abscisic acid (PP2CABA) proteins and uses thereof

A method of improving growth, stress tolerance and root architecture of a plant, comprising:

• (a) transforming plant cells with a DNA construct comprising an exogenous nucleic acid operably linked to a heterologous promoter, wherein the exogenous nucleic acid encodes short form type 2C protein phosphatase abscisic acid (PP2CABA) protein consisting of the amino acid sequence as set forth in SEQ ID NO:
• 4, to obtain transformed plant cells overexpressing said short form PP2CABA protein, and wherein said DNA construct and said exogenous nucleic acid do not encode long form PP2CABA protein having the amino acid sequence set forth in SEQ ID NO:
• 2;
• (b) growing said transformed plant cells obtained in step (a) to regenerate a plurality of transgenic plants overexpressing said short form PP2CABA protein;
• and
• (c) selecting a transgenic plant from said plurality of transgenic plants regenerated in step (b) that exhibits a lower lateral roots (LR) to primary roots (PR) ratio and a higher tolerance to abiotic osmotic or drought stress, as compared to (i) a control plant of the same species lacking said DNA construct and grown under identical growth conditions, and (ii) a transgenic plant overexpressing said long form PP2CABA protein and grown under identical growth conditions.