Challenges and Opportunities Arising from Host- Interactions to Outline Novel and Sustainable Control Strategies: The Key Role of RNA Interference.

The necrotrophic plant pathogenic fungus (Pers., 1794), the causative agent of gray mold disease, causes significant losses in agricultural production. Control of this fungal pathogen is quite difficult due to its wide host range and environmental persistence.

Exploring the patterns of evolution: Core thoughts and focus on the saltational model.

The Modern Synthesis, a pillar in biological thought, united Darwin's species origin concepts with Mendel's laws of character heredity, providing a comprehensive understanding of evolution within species. Highlighting phenotypic variation and natural selection, it elucidated the environment's role as a selective force, shaping populations over time. This framework integrated additional mechanisms, including genetic drift, random mutations, and gene flow, predicting their cumulative effects on microevolution and the emergence of new species.

Future-Proofing Agriculture: De Novo Domestication for Sustainable and Resilient Crops.

The worldwide agricultural system confronts a significant challenge represented by the increasing demand for food in the face of a growing global population. This challenge is exacerbated by a reduction in cultivable land and the adverse effects of climate change on crop yield quantity and quality. Breeders actively embrace cutting-edge omics technologies to pursue resilient genotypes in response to these pressing issues.

Ep2.2 inhibits growth of through the emission of volatile organic compounds, restricts leaf infection and primes defense genes.

The bacterium is known to be beneficial for plants and has been frequently isolated from the rhizosphere of crops. In the present work, we isolated from the phyllosphere of an ornamental plant an epiphytic strain of that we named Ep2.2 and investigated its possible application in crop protection.

Embryo Rescue in Plant Breeding.

Embryo rescue (ER) techniques are among the oldest and most successful in vitro tissue culture protocols used with plant species. ER refers to a series of methods that promote the development of an immature or lethal embryo into a viable plant. Intraspecific, interspecific, or intergeneric crosses allow the introgression of important alleles of agricultural interest from wild species, such as resistance or tolerance to abiotic and biotic stresses or morphological traits in crops.

Knockdown of and Virulence Genes by Exogenous Application of RNAi-Inducing dsRNA in .

is a pathogen of wide agronomic and scientific importance partly due to its tendency to develop fungicide resistance. Recently, there has been great interest in the use of RNA interference as a control strategy against . In order to reduce the possible effects on non-target species, the sequence-dependent nature of RNAi can be used as an advantage to customize the design of dsRNA molecules.

Induction of Somatic Embryogenesis in Plants: Different Players and Focus on WUSCHEL and WUS-RELATED HOMEOBOX (WOX) Transcription Factors.

In plants, other cells can express totipotency in addition to the zygote, thus resulting in embryo differentiation; this appears evident in apomictic and epiphyllous plants. According to Haberlandt's theory, all plant cells can regenerate a complete plant if the nucleus and the membrane system are intact. In fact, under in vitro conditions, ectopic embryos and adventitious shoots can develop from many organs of the mature plant body.

Innovative Approaches for Crop Improvement and Sustainable Management of Plant Disease in the Post-Genomic Era.

Safeguarding food supply in a world environment subject to sudden climate change, reducing the use of anthropogenic sources of pollution as much as possible, and using crops that must necessarily be increasingly resilient to biotic and abiotic stresses is a mandatory and ambitious necessity for the foreseeable future [...

Impact of transposable elements on the evolution of complex living systems and their epigenetic control.

Transposable elements (TEs) contribute to genomic innovations, as well as genome instability, across a wide variety of species. Popular designations such as 'selfish DNA' and 'junk DNA,' common in the 1980s, may be either inaccurate or misleading, while a more enlightened view of the TE-host relationship covers a range from parasitism to mutualism. Both plant and animal hosts have evolved epigenetic mechanisms to reduce the impact of TEs, both by directly silencing them and by reducing their ability to transpose in the genome.

Silencing of the Slt2-Type MAP Kinase in by Application of Exogenous dsRNA Affects Fungal Growth and Virulence on .

can attack over 500 genera of vascular plants and is considered the second phytopathogen in the 'top ten' for its economic importance. Traditional fungicides can be ineffective and with increasing fungicide resistance, new sustainable technologies are required. Lately, RNA interference-based fungicides are emerging for their potential uses in crop protection.

Ray flower initiation in the Helianthus radula inflorescence is influenced by a functional allele of the HrCYC2c gene.

The radiate pseudanthium, with actinomorphic disk flowers surrounded by showy marginal zygomorphic ray flowers, is the most common inflorescence in the Helianthus genus. In Helianthus radula, ray flower primordia are normally absent at the dorsal domain of the inner phyllaries (discoid heads) while the occurrence of radiate inflorescences is uncommon. In Helianthus spp.

The plastic genome: The impact of transposable elements on gene functionality and genomic structural variations.

Transposable elements (TEs) are DNA sequences that can change their position within genomes. TEs are present in most organisms and can be an important genomic component. Their activities are manifold: restructuring of genome size, chromosomal rearrangements, induction of gene mutations, and alteration of gene activity by insertion near or within promoters, intronic regions, or enhancer.

On the Trail of : Genome-Wide Discovery of CACTA Transposable Elements in Sunflower Genome.

Much has been said about sunflower ( L.) retrotransposons, representing the majority of the sunflower's repetitive component. By contrast, class II transposons remained poorly described within this species, as they present low sequence conservation and are mostly lacking coding domains, making the identification and characterization of these transposable elements difficult.

Energy conversion processes and related gene expression in a sunflower mutant with altered salicylic acid metabolism.

Salicylic acid (SA) is involved in several responses associated with plant development and defence against biotic and abiotic stress, but its role on photosynthetic regulation is still under debate. This work investigated energy conversion processes and related gene expression in the brachytic mutant of sunflower lingering hope (linho). This mutant was characterized by a higher ratio between the free SA form and its conjugate form SA O-β-D-glucoside (SAG) compared to wild type (WT), without significant changes in the endogenous level of abscisic acid and hydrogen peroxide.

The Dynamic Genetic-Hormonal Regulatory Network Controlling the Trichome Development in Leaves.

Plant trichomes are outgrowths developed from an epidermal pavement cells of leaves and other organs. Trichomes (also called 'hairs') play well-recognized roles in defense against insect herbivores, forming a physical barrier that obstructs insect movement and mediating chemical defenses. In addition, trichomes can act as a mechanosensory switch, transducing mechanical stimuli (e.

The Ha-ROXL gene is required for initiation of axillary and floral meristems in sunflower.

Axillary meristems (AMs) contribute to the growth of a plant, determining adult architecture and reproductive success in response to environmental stimuli. The missing flowers (mf) mutant of sunflower (Helianthus annuus) is defective in AM development. mf lacks shoot branching and ray flowers, occasionally producing few disk flowers.

Characterization of lingering hope, a new brachytic mutant in sunflower (Helianthus annuus L.) with altered salicylic acid metabolism.

Dwarf mutants are useful to elucidate regulatory mechanisms of plant growth and development. A brachytic mutant, named lingering hope (linho), was recently isolated from sunflower (Helianthus annuus). The aim of this report is the characterization of the mutant through genetic, morphometric, physiological and gene expression analyses.

Ligulate inflorescence of Helianthus × multiflorus, cv. Soleil d'Or, correlates with a mis-regulation of a CYCLOIDEA gene characterised by insertion of a transposable element.

Members of CYCLOIDEA (CYC)/TEOSINTE BRANCHED1 (TB1) transcription factor family are essential to control flower symmetry and inflorescence architecture. In the Helianthus annuus genome, ten CYC/TB1 genes have been identified. Studies performed on mutants recognised HaCYC2c as one of the key players controlling zygomorphism in sunflower.

The vascular plants: open system of growth.

What is fascinating in plants (true also in sessile animals such as corals and hydroids) is definitely their open and indeterminate growth, as a result of meristematic activity. Plants as well as animals are characterized by a multicellular organization, with which they share a common set of genes inherited from a common eukaryotic ancestor; nevertheless, circa 1.5 billion years of evolutionary history made the two kingdoms very different in their own developmental biology.

Molecular cloning, phylogenetic analysis, and expression patterns of LATERAL SUPPRESSOR-LIKE and REGULATOR OF AXILLARY MERISTEM FORMATION-LIKE genes in sunflower (Helianthus annuus L.).

The wild sunflower (Helianthus annuus) plants develop a highly branched form with numerous small flowering heads. The origin of a no branched sunflower, producing a single large head, has been a key event in the domestication process of this species. The interaction between hormonal factors and several genes organizes the initiation and outgrowth of axillary meristems (AMs).

A GRAS-like gene of sunflower (Helianthus annuus L.) alters the gibberellin content and axillary meristem outgrowth in transgenic Arabidopsis plants.

The GRAS proteins belong to a plant transcriptional regulator family that function in the regulation of plant growth and development. Despite their important roles, in sunflower only one GRAS gene (HaDella1) with the DELLA domain has been reported. Here, we provide a functional characterisation of a GRAS-like gene from Helianthus annuus (Ha-GRASL) lacking the DELLA motif.

Excisions of a defective transposable CACTA element (Tetu1) generate new alleles of a CYCLOIDEA-like gene of Helianthus annuus.

Tubular ray flower (turf) is a sunflower mutant that caught attention because it bears actinomorphic ray flowers, due to the presence of an active, although non-autonomous CACTA transposon (Tetu1) in the TCP domain of a CYCLOIDEA-like gene, HaCYC2c, a major regulator of sunflower floral symmetry. Here, we analyzed its excision rates in F3 population deriving from independent crosses of turf with common sunflower accessions. Our results suggest that the excision rate, ranging from 1.

Transposon-dependent induction of Vincent van Gogh's sunflowers: exceptions revealed.

The radiate sunflower inflorescence is composed by zygomorphic ray flowers and actinomorphic disk flowers. Studies performed on mutants identify HaCYC2c, a CYCLOIDEA (CYC)-like gene, as one of the key players controlling flower symmetry in sunflower. turf and tub mutants are characterized by a shift from zygomorphic to actinomorphic ray flowers, caused by insertion of transposable elements (TEs) in HaCYC2c gene.