This disclosure provides tobacco plants containing a PMT RNAi and tobacco plants having a mutation in PMT, and methods of making and using such plants.

Provided are isolated polynucleotides comprising a nucleic acid sequence encoding a polypeptide at least 80% identical to SEQ ID NO: 422, 362-421, 423-601, 2429-4085 and 4086, such as a polynucleotide which is at least 80% identical to SEQ ID NO: 260, 1-259, 261-361, 602-2427 and 2428, nucleic acid constructs comprising same, plant cells comprising same, transgenic plants expressing same, and methods of generating thereof for increasing the yield, biomass, growth rate, vigor, oil content, fiber yield, fiber quality, nitrogen use efficiency and/or abiotic stress tolerance of a plant.

Provided here are methods of using a mutated patatin-like phospholipase IIα (“pPLAIIα,” renamed here MATRILINEAL) to induce haploid induction in plants, cloning a pPLAIIα to induce haploid induction in plants, and genetically engineering a plant to contain a mutated pPLAIIα. Also provided are methods of applying topical and spray chemicals, lipids, and RNAi molecules to plants during pollination in order to induce haploid production. Further provided are methods of chemically treating plants during pollination to induce haploids while also reducing embryo abortion and increasing seed set.

The invention relates to methods of producing a desired phenotype in a plant by manipulation of gene expression within the plant. The method relates to means which inhibit the level of PK220 gene expression or activity, wherein a desired phenotype such as increased water use efficiency relative to a wild type control plant. The invention also relates to nucleic acid sequences and constructs useful such methods and methods of generating and isolating plants having decreased PK220 expression or activity.

The invention relates to methods of producing a desired phenotype in a plant by manipulation of gene expression within the plant. The method relates to means which inhibit the level of PK220 gene expression or activity, wherein a desired phenotype such as increased water use efficiency relative to a wild type control plant. The invention also relates to nucleic acid sequences and constructs useful such methods and methods of generating and isolating plants having decreased PK220 expression or activity.

Provided are isolated polynucleotides and nucleic acid constructs which comprise a nucleic acid sequence at least 80% identical to a nucleic acid sequence selected form the group consisting of SEQ ID NOs: 1-219, 367-5628, 9688-9700, and 9709-9752; and isolated polypeptides which comprise an amino acid sequence at least 80% homologous to an amino acid sequence selected from the group consisting of SEQ ID NOs: 220-366, 5629-9400, 9701-9708, and 9753-9796. Also provided are transgenic cells and plants expressing same and methods of using same for increasing yield, growth rate, biomass, vigor, oil content, seed yield, fiber yield, fiber quality, nitrogen use efficiency, and/or abiotic stress of a plant.

Provided are methods of increasing nitrogen use efficiency, yield, biomass, growth rate, vigor, oil content, fiber yield, fiber quality and/or abiotic stress tolerance of a plant by expressing within the plant an exogenous polynucleotide comprising a nucleic acid sequence at least 80% identical to SEQ ID NO:1-467, 785-3047; or an exogenous polynucleotide encoding a polypeptide at least 80% identical to SEQ ID NO:468-784, 3048-4333, 4335-4682. Also provided isolated polynucleotide comprising a nucleic acid sequence selected from the group consisting of SEQ ID NOs:1-467, 785-3047, which can be used to increase nitrogen use efficiency, yield, biomass, growth rate, vigor, oil content, fiber yield, fiber quality and/or abiotic stress tolerance of a plant.

Transgenic seed for crops with enhanced agronomic traits are provided by trait-improving recombinant DNA in the nucleus of cells of the seed where plants grown from such transgenic seed exhibit one or more enhanced traits as compared to a control plant. Of particular interest are transgenic plants that have increased yield. The present invention also provides recombinant DNA molecules for expression of a protein, and recombinant DNA molecules for suppression of a protein.

Provided are isolated polynucleotides at least 80% identical to SEQ ID NOs: 1-479, 813-5173, 8511, 8513, 8515, 8517, 8519, 8521, 8523, 9096-9141 and 9142; and isolated polypeptides at least 80% homologous to an amino acid sequence selected from the group consisting of SEQ ID NOs: 624, 480-623, 625-812, 5174-7015, 7017-7021, 7024, 7026-8510, 8512, 8514, 8516, 8518, 8520, 8522, 8524, 9143-9177, such as the polypeptides set forth in SEQ ID NO:480-812, 5174-8510, 8512, 8514, 8516, 8518, 8520, 8522, 8524, and 9143-9177, nucleic acid constructs comprising same, transgenic cells and plants expressing same and methods of using same for increasing yield, biomass, growth rate, vigor, oil content, fiber yield, fiber quality, nitrogen use efficiency, and/or abiotic stress tolerance of a plant.

Methods and materials for modulating biomass composition in plants are disclosed. For example, nucleic acids encoding biomass composition-modulating polypeptides are disclosed as well as methods for using such nucleic acids to transform plant cells. Also disclosed are plants having altered biomass composition and plant products produced from plants having altered biomass composition.