Isolated polypeptides and polynucleotides useful for increasing nitrogen use efficiency, abiotic stress tolerance, yield and biomass in plants

Abstract

Provided are methods of increasing nitrogen use efficiency, fertilizer use efficiency, yield, growth rate, vigor, biomass, oil content and/or abiotic stress tolerance of a plant by expressing within the plant an exogenous polynucleotide comprising a nucleic acid sequence encoding a polypeptide at least 80% identical to SEQ ID NO: 2560, 2557, 184, 238, 188, 154-156, 158-161, 163-183, 185-187, 189-197, 200-237, 239-264, 266-269, 1351, 1365-1425, 1429-1457, 1459, 1461-1730, 1735, 1739-2397, 2533-2541, 2544-2556, 2558, 2559, 2561-2562 or 2563. Also provided are isolated polynucleotides and polypeptides which can be used to increase nitrogen use efficiency, fertilizer use efficiency, yield, growth rate, vigor, biomass, oil content and/or abiotic stress tolerance of a plant of a plant.

What is claimed is: 
     
         1 . A method of increasing nitrogen use efficiency, fertilizer use efficiency, yield, growth rate, vigor, biomass, oil content, abiotic stress tolerance, and/or reducing time to flowering and/or time to inflorescence emergence of a plant, as compared to a native plant of the same species, which is grown under the same growth conditions, the method comprising over-expressing within the plant a polypeptide comprising an amino acid sequence at least 80% identical to the full-length amino acid sequence set forth by SEQ ID NO: 175 as compared to a native plant which is grown under the same growth conditions, thereby increasing the nitrogen use efficiency, fertilizer use efficiency, yield, growth rate, vigor, biomass, oil content, abiotic stress tolerance, and/or reducing the time to flowering or the time to inflorescence emergence of the plant as compared to the native plant of the same species, which is grown under the same growth conditions. 
     
     
         2 . The method of  claim 1 , further comprising selecting a plant over-expressing said polypeptide for an increased nitrogen use efficiency, an increased fertilizer use efficiency, an increased yield, an increased growth rate, an increased vigor, an increased biomass, an increased oil content, and/or an increased abiotic stress tolerance as compared to the native plant of the same species, which is grown under the same growth conditions. 
     
     
         3 . The method of  claim 2 , further comprising:
 (a) isolating a regenerable portion from plants selected according to the method of  claim 2 , to thereby obtain an isolated regenerable portion, and   (b) regenerating plants from said isolated regenerable portion.   
     
     
         4 . The method of  claim 1 , further comprising selecting a plant over-expressing said polypeptide for a reduced time to flowering and/or a reduced time to inflorescence emergence as compared to the native plant of the same species, which is grown under the same growth conditions. 
     
     
         5 . The method of  claim 4 , further comprising:
 (a) isolating a regenerable portion from plants selected according to the method of  claim 4 , to thereby obtain an isolated regenerable portion, and   (b) regenerating plants from said isolated regenerable portion.   
     
     
         6 . The method of  claim 1 , wherein said polypeptide comprises an amino acid sequence at least 95% identical to the full-length amino acid sequence set forth by SEQ ID NO: 175. 
     
     
         7 . The method of  claim 1 , wherein said polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 175 and 1457. 
     
     
         8 . The method of  claim 1 , wherein said polypeptide is expressed from a nucleic acid sequence at least 80% identical to SEQ ID NO: 2433. 
     
     
         9 . The method of  claim 1 , wherein said polypeptide is expressed from a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 2433, 38 and 393. 
     
     
         10 . The method of  claim 1 , further comprising growing the plant over-expressing said polypeptide under the abiotic stress. 
     
     
         11 . The method of  claim 1 , further comprising growing the plant over-expressing said polypeptide under nitrogen deficiency. 
     
     
         12 . The method of  claim 1 , wherein said abiotic stress is selected from the group consisting of salinity, drought, water deprivation, flood, etiolation, low temperature, high temperature, heavy metal toxicity, anaerobiosis, nutrient deficiency, nutrient excess, atmospheric pollution and UV irradiation. 
     
     
         13 . The method of  claim 12 , wherein said nutrient comprises nitrogen. 
     
     
         14 . A method of growing a crop, comprising growing a crop plant over-expressing a polypeptide comprising an amino acid sequence at least 80% identical to the full-length amino acid sequence set forth by SEQ ID NO: 175 as compared to a native plant of the same species which is grown under the same growth conditions, wherein said crop plant is derived from parent plants that over-express said polypeptide and that have been selected for at least one trait selected from the group consisting of: an increased nitrogen use efficiency, an increased fertilizer use efficiency, an increased yield, an increased growth rate, an increased vigor, an increased biomass, an increased oil content, an increased abiotic stress tolerance, a reduced time to flowering and a reduced time to inflorescence emergence, as compared to the native plant of the same species, which is grown under the same growth conditions, and said crop plant over-expressing said polypeptide has said increased nitrogen use efficiency, said increased fertilizer use efficiency, said increased yield, said increased growth rate, said increased vigor, said increased biomass, said increased oil content, said increased abiotic stress tolerance, said reduced time to flowering and/or said reduced time to inflorescence emergence, thereby growing the crop. 
     
     
         15 . The method of  claim 14 , wherein said polypeptide is selected from the group consisting of SEQ ID NOs: 175 and 1457. 
     
     
         16 . A nucleic acid construct comprising an isolated polynucleotide comprising a nucleic acid sequence encoding a polypeptide which comprises an amino acid sequence at least 80% identical to the full-length amino acid sequence set forth in SEQ ID NO: 175, and a heterologous promoter for directing transcription of said nucleic acid sequence in a host cell, wherein said amino acid sequence is capable of increasing nitrogen use efficiency, fertilizer use efficiency, yield, growth rate, vigor, biomass, oil content, abiotic stress tolerance, and/or reducing time to flowering or time to inflorescence emergence of a plant. 
     
     
         17 . The nucleic acid construct of  claim 16 , wherein said polypeptide comprises the amino acid sequence selected from the group consisting of SEQ ID NOs: 175 and 1457. 
     
     
         18 . The nucleic acid construct of  claim 16 , wherein said nucleic acid sequence is selected from the group consisting of SEQ ID NOs: 2433, 38 and 393. 
     
     
         19 . A plant cell comprising the nucleic acid construct of  claim 16 . 
     
     
         20 . A transgenic plant comprising the nucleic acid construct of  claim 16 .