Reducing cadmium accumulation in field grown tobacco plants

A non-naturally occurring and genetically modified plant or an artificially induced non-naturally occurring mutant plant or part thereof, having at least partially reduced expression or activity of at least two heavy metal ATPase (HMA) polypeptides encoded by at least two polynucleotide sequences, wherein said at least two polynucleotide sequences are selected from the group consisting of:

• (i) a polynucleotide sequences encoding a HMA polypeptides comprising an amino acid sequence having at least 95% amino acid sequence identity to the amino acid sequence as set forth in SEQ ID NO:
• 1, and a polynucleotide sequence encoding a HMA polypeptide comprising an amino acid sequence having at least 95% amino acid sequence identity to the amino acid sequence as set forth in SEQ ID NO:
• 2 and (ii) a polynucleotide sequences having at least 90% nucleotide sequence identity to the nucleotide sequence as set forth in SEQ ID NO:
• 3 and encoding a HMA polypeptide having at least 95% amino acid sequence identity to the amino acid sequence as set forth in SEQ ID NO:
• 1, and a polynucleotide sequence having at least 90% nucleotide sequence identity to the nucleotide sequence as set forth in SEQ ID NO:
• 4 and encoding a HMA polypeptide having at least 95% amino acid sequence identity to the amino acid sequence as set forth in SEQ ID NO:
• 2, and wherein said at least partially reduced expression or activity is by artificial mutagenesis or inhibitory RNAi construct mediated transformation of corresponding wild type plant or part thereof of the same species, wherein said non-naturally occurring and genetically modified plant or said artificially induced non-naturally occurring mutant plant or part thereof exhibits at least a 27% reduction in the accumulation of cadmium levels in leaf tissues of said non-naturally occurring and genetically modified plant or said artificially induced non-naturally occurring mutant plant or part thereof as compared to said corresponding wild type plant or part thereof of the same species and grown under identical growth conditions, wherein said non-naturally occurring and genetically modified plant or said artificially induced non-naturally occurring mutant plant or part thereof is grown under field conditions in the presence of cadmium, and wherein said non-naturally occurring and genetically modified plant or said artificially induced non-naturally occurring mutant plant or part thereof when grown under said field conditions in the presence of cadmium exhibits normal growth and development, and seed set which is identical and comparable to a wild type plant or part thereof of the same species grown under cadmium free conditions, and as compared to a hydroponically grown plant having said reduced expression or activity of said at least two heavy metal ATPase (HMA) polypeptides grown under said cadmium, and which shows stunted growth and does not produce seeds.