Sorghum alpha-amylase and coding gene and application thereof

The invention relates to sorghum alpha-amylase and a coding gene and application thereof. The amino acid sequence of the sorghum alpha-amylase is as shown in SEQID No.6, or is an amino acid sequence which is obtained through replacement, deletion or addition of one or more amino acids in the sequence as shown in the SEQID No.6 and has the same functions as that as shown in the SEQID No.6, and thenucleotide sequence coded by the gene is as shown in SEQID No.1 or is as shown in a sequence having 80% homology with the sequence. When the sorghum alpha-amylase disclosed by the invention is expressed at the pollen development period under driving of a pollen specificity promoter, starch can be degraded in advance, energy cannot be provided for pollen germination, the pollen germination is restrained, and pollen abortion is caused. The sorghum alpha-amylase disclosed by the invention can effectively prevent transgenic pollen from escaping, and can also be used for maintaining the homozygosisrecessive state of male s