Irma Roig-Villanova

• PhD
• PostDoc Position at Center for Research in Agricultural Genomics

Among the Mediterranean horticultural landraces, garlic is one of the crops most threatened by genetic erosion. Due to its sexual sterility and to the incidence of seed-borne diseases, historical varieties have been widely replaced by commercial cultivars. In Catalonia, despite the historical relevance of the crop, solely the Belltall garlic landra...

Non-trellised culture of tomato is gaining interest among farmers cultivating long shelf-life (LSL) landraces because of the reduction in production costs. This cropping system can benefit from the selection of determinate growth genotypes, mirroring the advancements achieved in processing tomatoes. With this aim, and profiting from the natural var...

In sun-loving plants, detection of the proximity of nearby competitors triggers a set of responses known as the shade-avoidance syndrome (SAS). These responses will help the plant to acclimate to the proximity of vegetation that might compromise light availability and limit plant development. Plants sense the presence of nearby competitor vegetatio...

When growing in search for light, plants can experience continuous or occasional shading by other plants. Plant proximity causes a decrease in the ratio of R to far-red light (low R:FR) due to the preferential absorbance of R light and reflection of FR light by photosynthetic tissues of neighboring plants. This signal is often perceived before actu...

When growing in search for light, plants can experience continuous or occasional shading by other plants. Plant proximity causes a decrease in the ratio of red to far red light (low R:FR) due to the preferential absorbance of red light and reflection of far red light by photosynthetic tissues of neighboring plants. This signal is often perceived be...

The MADS-domain transcription factor SEEDSTICK (STK) controls several aspects of plant reproduction. STK is co-expressed with CESTA (CES), a basic Helix-Loop-Helix (bHLH) transcription factor-encoding gene. CES was reported to control redundantly with the brassinosteroid positive signaling factors BRASSINOSTEROID ENHANCED EXPRESSION1 (BEE1) and BEE...

The BASIC PENTACYSTEINE (BPC) GAGA (C‐box) binding proteins belong to a small plant transcription factor family. We previously reported that BPCs of class I bind directly to C‐boxes in the SEEDSTICK (STK) promoter and the mutagenesis of these cis‐elements affects STK expression in the flower. The MADS‐domain factor SHORT VEGETATIVE PHASE (SVP) is a...

Background: Rice grain production is susceptible to a changing environment that imposes both biotic and abiotic stress conditions. Cold episodes are becoming more frequent in the last years and directly affect rice yield in areas with a temperate climate. Rice is particularly susceptible to cold stress during the reproductive phase, especially in...

Plants have evolved two major ways to deal with nearby vegetation or shade: avoidance and tolerance. Moreover, some plants respond to shade in different ways; for example, Arabidopsis thaliana undergoes an avoidance response to shade produced by vegetation, but its close relative Cardamine hirsuta tolerates shade. How plants adopt opposite strategi...

Plants detect neighboring vegetation as potential competitors for resources. Vegetation proximity is perceived by changes in the red (R) to far-red (FR) ratio (R:FR) through the phytochrome photoreceptors. To face this challenge, many plants have evolved the strategy to avoid shade, displaying a series of responses known as the shade avoidance synd...

Light perception and hormone signaling in plants are likely connected at multiple points. Light conditions, perceived by photoreceptors, control plant responses by altering hormone concentration, tissue sensitivity, or a combination of both. Whereas it is relatively straightforward to assess the light effects on hormone levels, hormone sensitivity...

Seed dispersal is an essential trait that enables colonization of new favorable habitats, ensuring species survival. In plants with dehiscent fruits, such as Arabidopsis, seed dispersal depends on two processes: the separation of the fruit valves that protect the seeds (fruit dehiscence), and the detachment of the seeds from the funiculus connectin...

When plants grow in close proximity, basic resources such as light might become limiting. Under such conditions, plants respond to anticipate and/or adapt to the light shortage, a process known as the shade avoidance syndrome (SAS). After a genetic screening using a shade-responsive luciferase reporter line (PHYB:LUC), we identified DRACULA2 (DRA2)...

In high density of vegetation, plants detect neighbors by perceiving changes in light quality through phytochrome photoreceptors. Close vegetation proximity might result in competition for resources, such as light. To face this challenge, plants have evolved two alternative strategies: to either tolerate or avoid shade. Shade-avoiding species gener...

The seed represents the unit of reproduction of flowering plants, capable of developing into another plant, and to ensure the survival of the species under unfavorable environmental conditions. It is composed of three compartments: seed coat, endosperm and embryo. Proper seed development depends on the coordination of the processes that lead to see...

In spermatophytes the ovules upon fertilization give rise to the seeds. It is essential to understand the mechanisms that control ovule number and development as they ultimately determine the final number of seeds and, thereby, the yield in crop plants. In Arabidopsis thaliana, ovules arise laterally from a meristematic tissue within the carpel ref...

Bsister proteins form a clade of MADS-box transcription factors that originated 300 million years ago, after ferns diverged but before Angiosperms and Gymnosperms lineages did. Thus, Bsister proteins have been found in both Gymnosperm and Angiosperm species such as paddy oat (Gnetum gnemon), ginkgo, yew (Taxus baccata), rape seed, rice, maize, whea...

Land plants are characterised by haplo-diploid life cycles, and developing ovules are the organs in which the haploid and diploid generations coexist. Recently it has been shown that hormones such as auxin and cytokinins play important roles in ovule development and patterning. The establishment and regulation of auxin levels in cells is predominan...

PIN2, PIN4, PIN5, PIN6 and PIN7 are not expressed in developing ovules. (A) a PIN2:PIN2-GFP ovule at stage 2–IV and a primary root (B); (C) a PIN4:GUS ovule at stage 2–III and a primary root (D); (E) in situ hybridisation to developing ovules (stage 2–III) using an antisense PIN5 probe, and to developing stamens and carpel leaves (F). (G) a PIN6:GU...

pDEH9 is an ovule-specific promoter also in Arabidopsis thaliana. The Antirrhinum majus DEF9 promoter (pDEH9) drives reporter gene expression (GUS) only in developing ovules, the promoter being active from stage II (A) to stage 3–V (E). fg, female gametophyte; ii, inner integument; oi, outer integument; fun, funiculus; nu, nucellus. (TIF)

A Analysis of pin1-5 developing ovules. 20 pistils collected from 4 independent plants have been analysed. B and C Analysis of T2 pDEFH9:amiPIN1 and pDEFH9:amiPIN1-3 plants. The total number of ovules and the percentage of ovule abortion are reported. 5 siliques per individual were observed, and 15 independent lines have been analysed. Aberrant emb...

Ovule development and the auxin response. (A,C) Confocal analysis of wild-type ovules, (B,D) DR5rev:3XVENUS-N7 ovules at the corresponding stages. In C and D the endothelium begins to develop (see arrow) whereas the nucellar cells degenerate and accordingly the fluorescent nuclear auxin response is no longer detectable, though the auxin response is...

YUC4 is expressed in developing ovules. The YUC4 promoter (pYUC4) does not drive reporter gene expression (GUS) in developing ovules between stages 1–I (A) and 3–I (C). Reporter gene activity begins to be detected in ovules at stage 3–II (D) and it is maintained until stage 3–V (E). fg, female gametophyte; ii, inner integument; oi, outer integument...

PIN1 expression in pDEFH9:amiPIN1 flowers. Real-time PCR to evaluate PIN1 expression in pDEFH9:amiPIN1 flowers. Two pairs of PIN1 specific primers were employed (orange and green). (TIF)

The auxin response in normal and mutated ovules of pDEFH9:amiPIN1 plants. (A) The DR5rev:GFP promoter is active in mutated ovules unable to complete megagametogenesis. fg, female gametophyte; ii, inner integument; oi, outer integument; fun, funiculus; nu, nucellus Scale bars: 20 µm. (TIF)

Sequences of oligonucleotide primers used in this work. (DOCX)

The shade avoidance syndrome (SAS) refers to a set of plant responses initiated after perception by the phytochromes of light with a reduced red to far-red ratio, indicative of vegetation proximity or shade. These responses, including elongation growth, are aimed to anticipate eventual shading from potential competitor vegetation by overgrowing the...

BASIC PENTACYSTEINE (BPC) transcription factors have been identified in a large variety of plant species. In Arabidopsis thaliana there are seven BPC genes, which, except for BPC5, are expressed ubiquitously. BPC genes are functionally redundant in a wide range of developmental processes. Recently, we reported that BPC1 binds to guanine and adenine...

PAR1 is an atypical basic-helix-loop-helix (bHLH) protein that negatively regulates the shade avoidance syndrome in Arabidopsis thaliana acting as a transcriptional cofactor. Consistently with this function, PAR1 has to be in the nucleus to display biological activity. Previous structure-function analyses revealed that the N-terminal region of PAR1...

The shade avoidance syndrome (SAS) allows plants to anticipate and avoid shading by neighbouring plants by initiating an elongation growth response. The phytochrome photoreceptors are able to detect a reduction in the red:far red ratio in incident light, the result of selective absorption of red and blue wavelengths by proximal vegetation. A shade-...

The BASIC PENTACYSTEINE (BPC) proteins are a plant-specific transcription factor family that is present throughout land plants. The Arabidopsis BPC proteins have been categorized into three classes based on sequence similarity, and we demonstrate that there is functional overlap between classes. Single gene mutations produce no visible phenotypic e...

Basic helix-loop-helix proteins (bHLHs) are found throughout the three eukaryotic kingdoms and constitute one of the largest families of transcription factors. A growing number of bHLH proteins have been functionally characterized in plants. However, some of these have not been previously classified. We present here an updated and comprehensive cla...

Plants sense the presence of competing neighboring vegetation as a change in light quality: i.e. they sense the reduced ratio of red light to far-red light. The responses to shade are generally referred to as the shade avoidance syndrome (SAS), and involve various developmental changes intended to outgrow or outcompete the neighboring plants. Here,...

PHYTOCHROME RAPIDLY REGULATED1 (PAR1) and PAR2 are two negative regulators of shade avoidance syndrome (SAS) responses in Arabidopsis. PAR1 and PAR2 belong to the bHLH family of transcription factors and act as direct transcriptional repressors of auxin- and brassinosteroid-responsive genes. These observations led us to propose that PAR1 and PAR2 m...

Recent work has increased our understanding of the molecular and cellular mechanisms of the phytochrome family of photoreceptors in controlling plant photomorphogenesis. However, the importance of long-distance communication in controlling light responses has received relatively little attention and is poorly understood. In this article, by taking...

Plants sense the presence of potentially competing nearby individuals as a reduction in the red to far-red ratio of the incoming light. In anticipation of eventual shading, a set of plant responses known as the shade avoidance syndrome (SAS) is initiated soon after detection of this signal by the phytochrome photoreceptors. Here we analyze the func...

The phytochrome (phy) photoreceptors modulate plant development after perception of light. Upon illumination of etiolated seedlings, phys initiate a transcriptional cascade by directly transducing light signals to the promoters of genes encoding regulators of morphogenesis. In light-grown plants, however, little is known about the transcriptional c...

One factor which affects the profitability of marketing bananas is that they have to be transported over long distances. Because of this, they have to be specially treated to delay ripening so that they survive long shipment and reach the consumer in the most palatable and appealing state possible. One such treatment involves the use of nitrous oxi...

The effect of nitrous oxide (N2O) alone or in combination with reduced oxygen (O2) levels on the postharvest ripening of mature green banana fruit was investigated. Banana fruit stored at 20 .C were exposed, in a flow-through system, to 20, 40, 60 and 80% N2O with 8.20% O2 for 2, 3, 5 and 10 days, as well as in continuous treatments, and compared t...

Filing Date: 2004-05-05.-- Priority Data: ES (2003-05-06) (P200-30-10) The object of the invention is a procedure which permits delayed onset of ripening of bananas, while at the same time retaining suitable organoleptic and quality characteristics. The procedure is carried out in a non-controlled modified atmosphere, at a temperature between 12°C...