Claim 1 A transgenic plant transformed with a polynucleotide comprising a nucleotide sequence; wherein the nucleotide sequence encodes a polypeptide having at least 90% amino acid sequence identity to SEQ ID NO: 162, the polypeptide is a member of the Myb protein family, and the polypeptide comprises a Myb domain;wherein the polypeptide regulates expression of at least one gene;and wherein when the polypeptide is expressed in the transgenic plant, said expression results in the transgenic plant having greater tolerance to heat as compared to a wild-type plant of the same species.
