This disclosure concerns the use of endogenous plant RNAi machinery to preferentially or specifically reduce transgene expression. In some embodiments, the disclosure concerns specific reduction of transgene expression in seed tissues of a dicot plant.

The invention relates to transgenic plants comprising an inverted-repeat construct which triggers post-transcriptional gene silencing of an endogenous visual reporter gene driven by a tissue-specific promoter wherein said tissue is relevant for pathogen entry, propagation or replication and their uses for screening natural or synthetic molecules, microorganisms or extracts from micro- or macro-organisms for their potential ability to inhibit pathogen entry, propagation or replication in plants by enhancing PTGS or for characterizing the mode of action of natural or synthetic molecules that are known to enhance plant disease resistance through an ill-defined mode of action.

The present invention provides constructs comprising a transgene operable linked to a novel tissue-specific maize promoter. Methods of using the constructs to drive tissue-specific transgene expression in a maize plant and maize plants comprising the constructs are also provided.

The present invention provides novel DNA molecules and constructs, including their nucleotide sequences, useful for modulating gene expression in plants and plant cells. The invention also provides transgenic plants, plant cells, plant parts, seeds, and commodity products comprising the DNA molecules operably linked to heterologous transcribable polynucleotides, along with methods of their use.

Provided herein are methods for using RNAi molecules targeting a proteasome beta 5 (PSMB5) gene for controlling Coleopteran insects, methods for producing RNAi molecules targeting PSMB5, and compositions comprising RNAi molecules targeting PSMB5.

Compositions and methods for improving plant growth are provided herein. Compositions comprise promoter sequences that direct expression of an operably linked nucleotide in a developmentally regulated manner. Polynucleotides, polypeptides, and expression constructs for expressing genes of interest whose expression may improve agronomic properties including but not limited to crop yield, biotic and abiotic stress tolerance, and early vigor, plants comprising the polynucleotides, polypeptides, and expression constructs, and methods of producing transgenic plants are also provided.

Polynucleotides and polypeptides incorporated into expression vectors are introduced into plants and were ectopically expressed. These polypeptides may confer at least one regulatory activity and increased yield, increased resource use efficiency, increased water use efficiency, increased light use efficiency, increased photosynthetic capacity, increased photosynthetic rate, increased photosynthetic resource use efficiency, greater vigor, and/or greater biomass as compared to a control plant.

Compositions and methods for reducing the level of nornicotine and N-nitrosonornicotine (NNN) in tobacco plants and plant parts thereof are provided. The compositions comprise isolated polynucleotides and polypeptides for a root-specific nicotine demethylases, CYP82E10, and variants thereof, that are involved in the metabolic conversion of nicotine to nornicotine in these plants. Compositions of the invention also include tobacco plants, or plant parts thereof, comprising a mutation in a gene encoding a CYP82E10 nicotine demethylase, wherein the mutation results in reduced expression or function of the CYP82E10 nicotine demethylase. Seed of these tobacco plants, or progeny thereof, and tobacco products prepared from the tobacco plants of the invention, or from plant parts or progeny thereof, are also provided. Methods for reducing the level of nornicotine, or reducing the rate of conversion of nicotine to nornicotine, in a tobacco plant, or plant part thereof are also provided. The methods comprise introducing into the genome of a tobacco plant a mutation within at least one allele of each of at least three nicotine demethylase genes, wherein the mutation reduces expression of the nicotine demethylase gene, and wherein a first of these nicotine demethylase genes encodes a root-specific nicotine demethylase involved in the metabolic conversion of nicotine to nornicotine in a tobacco plant or a plant part thereof. The methods find use in the production of tobacco products that have reduced levels of nornicotine and its carcinogenic metabolite, NNN, and thus reduced carcinogenic potential for individuals consuming these tobacco products or exposed to secondary smoke derived from these products.

The present disclosure identifies new genes which have the potential to increase broad acre yield in crops. This disclosure is based upon our fundamental knowledge of light signal transduction and our understanding of the roles these genes play in regulating plant growth and development in response to light. Transgenic plants with gain- or loss-of-function of one of these genes, or in combination, are expected to show significant improvements in broad acre yield and stress tolerance.

This invention discloses a constitutive promoter from the Taro bacilliform virus (TaBV) for expression of foreign or endogenous coding sequences in plants, including dicotyledonous and monocotyledonous plants. The invention also discloses a chimeric nucleic acid construct comprising the promoter of the invention operably linked to a foreign or endogenous polynucleotide that codes for a protein of interest or a transcript capable of modulating expression of a target gene. The invention further discloses transformed plant cells, as well as differentiated plants and plant parts, containing the construct. Methods for diagnosis and treatment of viral infections, especially badnaviral infections, are also disclosed.