Method for influencing pollen development by modifying sucrose metabolism

The recombinant nucleic acid molecule, comprising

• a) regulatory sequences of a promoter that is active in anthers, in the tapetum and/or in pollen;
• b) operatively linked thereto a DNA sequence which codes for a protein having the enzymatic activity of a sucrose isomerase;
• and
• c) operatively linked thereto regulatory sequences which can serve as transcription, termination and/or polyadenylation signals in plant cells.

A method for generating male fertile hybrid plants, comprising the following steps:

• a) producing a first transgenic male sterile parent plant, comprising a nucleic acid molecule which codes for a protein having the enzymatic activity of a sucrose isomerase,
• b) producing a second transgenic parent plant, comprising a nucleic acid molecule which codes for a protein having the enzymatic activity of a palatinase and/or a protein having the enzymatic activity of a trehalulase,
• c) crossing the first parent plant with the second parent plant to generate a hybrid plant,
• wherein the hybrid plant is male fertile.

A method for generating male fertile hybrid plants comprising the following steps:

• a) producing a first transgenic male sterile parent plant comprising a nucleic acid molecule which codes for a protein having the enzymatic activity of a sucrose isomerase,
• b) producing a second transgenic parent plant comprising a nucleic acid molecule which codes for a protein which has the biological activity of a sucrose isomerase inhibitor,
• c) crossing the first parent plant with the second parent plant for generating a hybrid plant,
• wherein the hybrid plant is male fertile.

A method for generating male fertile hybrid plants comprising the following steps:

• a) producing a first transgenic male sterile parent plant comprising a nucleic acid molecule which codes for a protein having the enzymatic activity of a sucrose isomerase,
• b) producing a second transgenic parent plant comprising a nucleic acid molecule which codes for a ribozyme which is directed against sucrose isomerase mRNA,
• c) crossing the first parent plant with the second parent plant for generating a hybrid plant,
• wherein the hybrid plant is male fertile.

A method for generating male fertile hybrid plants, comprising the following steps:

• a) producing a first transgenic male sterile parent plant comprising a nucleic acid molecule which codes for a protein having the enzymatic activity of a sucrose isomerase,
• b) producing a second transgenic parent plant comprising a nucleic acid molecule which codes for a sucrose isomerase antisense or sense RNA,
• c) crossing the first parent plant with the second parent plant to generate a hybrid plant,
• wherein the hybrid plant is male fertile.