The present invention is directed to a transgenic maize plant or a part thereof comprising as transgene a nucleic acid capable of expressing a cell wall invertase or a functional part thereof, preferably a Chenopodium rubrum cell wall invertase or a functional part thereof, wherein as a result of the expression of the cell wall invertase or a functional part thereof the transgenic maize plant exhibits an enhanced tolerance to abiotic stress and/or an increased yield, to a method of producing such transgenic maize plant, to method of enhancing the tolerance to abiotic stress of a maize plant and/or of increasing yield potential of a maize plant, to a nucleic acid capable of expressing a cell wall invertase or a functional part thereof, preferably a Chenopodium rubrum cell wall invertase or a functional part thereof, to a vector comrpsisng such nucleic acid, the use of the nucleic acid or vector for enhancing the tolerance to abiotic stress of a maize plant, for increasing yield potential of a maize plant and/or for protecting a maize plant against abiotic stress, and to a method for production of ethanol or methane from transgenic maize plant or a part thereof of the invention.