Rogelio Santiago

Spanish National Research Council | CSIC · Crop Production

Fusarium verticillioides is a causal agent of maize ear rot and produces fumonisins, which are mycotoxins that are toxic to animals and humans. In this study, quantitative trait loci (QTLs) and bulk-segregant RNA-seq approaches were used to uncover genomic regions and pathways involved in resistance to Fusarium ear rot (FER) and to fumonisin accumu...

Maize stalks support leaves and reproductive structures and functionally support water and nutrient transport; besides, their anatomical and biochemical characteristics have been described as a plant defense against stress, also impacting economically important applications. In this study, we evaluated agronomical and stem description traits in a s...

Maize kernel is exposed to several fungal species, most notably Fusarium verticillioides , which can contaminate maize kernels with fumonisins. In an effort to increase genetic gains and avoid the laborious tasks of conventional breeding, the use of marker-assisted selection or genomic selection programs was proposed. To this end, in the present st...

Higher hydroxycinnamate content makes maize tissues more recalcitrant to damage by insects, less digestible by ruminants, and less suitable for biofuel production. In a Genome Wide Association Analysis (GWAS) study carried out in a maize MAGIC population, we identified 24 SNPs associated with esterified cell wall-bound hydrox-ycinnamates, that repr...

With a high potential to generate biomass, maize stover arises as an outstanding feedstock for biofuel production. Maize stover presents the added advantage of being a multiple exploitation of the crop as a source of food, feed, and energy. In this study, contrasting groups of recombinant inbred lines (RILs) from a maize multiparent advanced genera...

Corn borers are the most important pest affecting maize. Resistance to corn borer attack may compromise plant fitness being detrimental for some important agronomic traits such as yield. Against the attack of this pest, cell wall-bound hydroxycinnamates have been previously described as a possible defense mechanism. In this study, agronomic charact...

Background Besides the use of maize grain as food and feed, maize stover can be a profitable by-product for cellulosic ethanol production, whereas the whole plant can be used for silage production. However, yield is reduced by pest damages, stem corn borers being one of the most important yield constraints. Overall, cell wall composition is key in...

The cell wall putatively plays a role in host-plant resistance to phytopathogens. Here, we investigated which cell wall-bound phenolic compounds have determining roles in maize (Zea mays) resistance to attack by the Mediterranean corn borer Sesamia nonagrioides (Lefèbvre). Diverse sets of maize genotypes having contrasting hydroxycinnamate contents...

Lodging is one of the causes of maize (Zea mays L.) production losses worldwide and, at least, the resistance to stalk lodging has been positively correlated with stalk strength. In order to elucidate the putative relationship between cell wall, stalk strength and lodging resistance, twelve maize inbreds varying in rind penetration strength and lod...

Cellulosic ethanol derived from fast growing C4 grasses could become an alternative to finite fossil fuels. With the potential to generate a major source of lignocellulosic biomass, maize has gained importance as an outstanding model plant for studying the complex cell wall network and also to optimize crop breeding strategies in bioenergy grasses....

Forage feedstock is the greatest source of energy for livestock. Unfortunately, less than 50% of their fiber content is actually digested and assimilated by the ruminant animals. This recalcitrance is mainly due to the high concentration of plant cell wall material and to the limited digestion of the fiber by the microorganisms. A Genome-Wide Assoc...

Background: Mechanical resistance due to higher hydroxycinnamate content makes maize tissues more recalcitrant to damage by insects, less digestible by ruminants, and less suitable for biofuel production. The integrated study of the maize functional genetic variability for each hydroxycinnamate component could be crucial to identify relevant geneti...

Background: Besides the use of maize grain as food and feed, maize stover can be a profitable by-product for cellulosic ethanol production, whereas the whole plant can be used in silage production. However, yield is reduced by pest damages, where stem corn borers are one of the most important factors limiting yield. Overall, cell wall composition i...

Food contamination with mycotoxins is a worldwide concern, because these toxins produced by several fungal species have detrimental effects on animal and/or human health. In maize, fumonisins are among the toxins with the highest threatening potential because they are mainly produced by Fusarium verticillioides, which is distributed worldwide. Plan...

Abstract: Maize (Zea mays L.) from the Algerian Sahara was adapted to arid conditions and has been used for food and feed. The objective of this work was to assess the potential value of Saharan maize for saccharification and nutritive value under drought conditions. Eighteen maize populations from the Algerian Sahara were evaluated under drought a...

Background: Cellulosic ethanol derived from fast growing C4 grasses could become an alternative to finite fossil fuels. With the potential to generate a major source of lignocellulosic biomass, maize has gained importance as an outstanding model plant for studying the complex cell wall network, and as a model to optimize crop breeding strategies in...

Background: The structural reinforcement of cell walls by hydroxycinnamates has a significant role in defense against pests and pathogens, but it also interferes with forage digestibility and biofuel production. Elucidation of maize genetic variations that contribute to variation for stem hydroxycinnamate content could simplify breeding for cell w...

Background: Corn borers constitute an important pest of maize around the world; in particular Sesamia nonagrioides Lefèbvre, named Mediterranean corn borer (MCB), causes important losses in Southern Europe. Methods of selection can be combined with transgenic approaches to increase the efficiency and durability of the resistance to corn borers. Pr...

Background Plant breeding has been proposed as one of the most effective and environmentally safe methods to control fungal infection and to reduce fumonisin accumulation. However, conventional breeding can be hampered by the complex genetic architecture of resistance to fumonisin accumulation and marker-assisted selection is proposed as an efficie...

Plant long-term response against chewing insects could become stronger than initial reactions and even turn into systemic. The objectives of the present study were 1) to evaluate whether the long-running attack to the stem by corn borers can improve the stem antibiotic properties; 2) to check whether hydroxycinnamic acids could be involved in this...

Alternative approaches to linkage and association mapping using inbred panels may allow further insights into loci involved in resistance to Fusarium ear rot and lead to the discovery of suitable markers for breeding programs. Here, the suitability of a maize multiparent advanced-generation intercross population for detecting quantitative trait loc...

Plants defend themselves against herbivores by activating a plethora of genetic and biochemical mechanisms aimed at reducing plant damage and insect survival. The short-term plant response to insect attack is well understood, but less is known about the maintenance of this response over time. We performed transcriptomic and metabolomics analyses in...

We compared two methods with different sample pretreatment, hydrolysis, and separation procedures to extract cell wall-bound phenolics. The samples were pith and rind tissues from six maize inbred lines reportedly containing different levels of cell wall-bound phenolics. In method 1, pretreated samples were extracted with a C18 solid-phase extracti...

The estimate of worldwide annual yield loss in maize due to pests ranges from 7 to 20%. Insects are among the most important pests of maize at all stages of development, from germination to grain filling, and can even be the main spoilers of grains in storage facilities. Each particular insect species shows preference for attacking a specific maize...

Mediterranean Corn Borer (MCB), Sesamia nonagrioides Lef, is an important pest of maize in temperate areas causing significant stalk lodging and yield losses. The main focus of the current study were to determine possible changes in chemical traits (phenols, flavonoids, anthocyanins, sugars, fibers, and lignin) during plant development after the fl...

Background Plants can respond to insect attack via defense mechanisms that reduce insect performance. In this study, we examined the effects of several treatments applied to two maize genotypes (one resistant, one susceptible) on the subsequent growth and survival of Sesamia nonagrioides Lef. (Mediterranean corn borer, MCB) larvae. The treatments w...

The direct response of a divergent selection programme for total cell wall ester-linked diferulate concentration in maize pith stalk tissues and its indirect effect on cell wall degradability and corn borer resistance have been previously evaluated. Since increased total diferulate concentration is expected to improve crop performance in response t...

Previous results suggest a relationship between maize hydroxycinnamate concentration in the pith tissues and resistance to stem tunneling by the Mediterranean corn borer (MCB, Sesamia nonagrioides Lef.) larvae. This study performs a more precise experiment, mapping a F2 derived from the cross between two inbreds with contrasting levels for hydroxyc...

Fusarium graminearum and F. verticillioides as well as the mycotoxins they produce, deoxynivalenol, among others, and fumonisins, respectively, are world-wide distributed. These mycotoxins pose the main feed and food threat of maize cultivated in temperate areas, but plant breeding is emerging as an effective and environmentally safe method to cont...

Contamination of maize with fumonisins depends on the environmental conditions; the maize resistance to contamination and the interaction between both factors. Although the effect of environmental factors is a determinant for establishing the risk of kernel contamination in a region, there is sufficient genetic variability among maize to develop re...

Coumarate 3-hydroxylase (C3H) catalyzes a key step of the synthesis of the two main lignin subunits, guaiacyl (G) and syringyl (S) in dicotyledonous species. As no functional data are available in regards to this enzyme in monocotyledonous species, we generated C3H1 knock-down maize plants. The results obtained indicate that C3H1 participates in li...

Maize (Zea mays L.) suspension-cultured cells with up to 70% less cellulose were obtained by stepwise habituation to dichlobenil (DCB), a cellulose biosynthesis inhibitor. Cellulose deficiency was accompanied by marked changes in cell wall matrix polysaccharides and phenolics as revealed by FTIR spectroscopy. Cell wall compositional analysis indica...

There is strong evidence to suggest that cross-linking of cell wall polymers through ester-linked diferulates has a key role in plant resistance to pests; however, direct experimentation to provide conclusive proof is lacking. This study presents an evaluation of the damage caused by two corn borer species on six maize populations particularly sele...

There is not any conclusive result about the most suitable trait for performing pedigree selection for improving maize performance against corn borer attack: tunnel length or stalk breakage. We have used simultaneously both selection traits in the same genetic backgrounds and the objective of the present work has been to compare the suitability of...

In northwestern Spain, where weather is rainy and mild throughout the year, Fusarium verticillioides is the most prevalent fungus in kernels and a significant risk of fumonisin contamination has been exposed. In this study, detailed information about environmental and maize genotypic factors affecting F. verticillioides infection, fungal growth and...

Genetic improvement is an emerging method to reduce the levels of fumonisin (FB) contamination in maize, but breeding advances depend on the development of suitable methods to accurately assess the performance of different cultivars. Our study focused on characterizing a local isolate of Fusarium verticillioides; comparing artificial inoculation te...

Fusarium poses food and feed safety problems because most species produce mycotoxins. To understand the epidemiology of the Fusarium disease, efforts must focus more precisely on how environmental variables affect disease presence. The objectives of the present study were to monitor the occurrence of Fusarium species in maize kernels in northwester...

Insect activity has long been associated with Fusarium infection. The objectives of the current study were 1) to estimate the impact of Mediterranean corn borer, Sesamia nonagrioides Lefèbvre, damage on fumonisin contamination in the maize kernel by comparing fumonisin contamination under infestation and protected conditions, and 2) to measure the...

Fusarium ear rot is a common disease of maize that affects food and feed quality globally. Resistance to the disease is highly quantitative, and maize breeders have difficulty incorporating polygenic resistance alleles from unadapted donor sources into elite breeding populations without having a negative impact on agronomic performance. Identificat...

In cereals, the primary cell wall is built of a skeleton of cellulosic microfibrils embedded in a matrix of hemicelluloses and smaller amounts of pectins, glycoproteins and hydroxycinnamates. Later, during secondary wall development, p-coumaryl, coniferyl and sinapyl alcohols are copolymerized to form mixed lignins. Several of these cell wall compo...

This study was undertaken to identify tissue-specific biochemical traits that may be targeted in breeding programs for improving forage digestibility. We compared cell wall chemical composition and 24- and 96-h in vitro degradabilities in separated pith and rind tissues of lower stem internodes from six maize (Zea mays L) inbred lines. Across genot...

To elucidate the role of the length of the internode basal ring (LIBR) in resistance to the Mediterranean corn borer (MCB), we carried out a divergent selection program to modify the LIBR using two maize synthetic varieties (EPS20 and EPS21), each with a different genetic background. We investigated the biochemical mechanisms underlying the relatio...

In spite of multiple studies elucidating individual defense mechanisms against stalk borer feeding, little information is available about the plant response to these members of Lepidoptera. Four maize inbred lines were cultivated in a greenhouse and challenged with larvae of the corn borer Sesamia nonagrioides. Transcriptome and biochemical analyse...

In the current study, the hydroxycinnamic acids in silks of diverse maize inbred lines differing in Fusarium resistance were determined at several times after inoculation with Fusarium graminearum or sterile water as control. The main objective was to determine the possible relationship between the hydroxycinnamic acid changes in silks and ear rot...

With 2 tables Length of the internode basal ring (LIBR) in maize is a morphological character that has been associated with resistance to Mediterranean corn borer (MCB), Sesamia nonagrioides Lef. The present study is the first research to evaluate the usefulness of this trait in breeding programmes. Six maize hybrids, from a complete diallel set of...

Mediterranean corn borer (MCB) (Sesamia nonagrioides Lef) and European corn borer (ECB) (Ostrinia nubilalis Hbn) are the most important biotic stresses of maize in Europe. The first selection program to improve stalk resistance to MCB was carried out in the maize population EPS12. It has shown that selection was effective to improve stalk resistanc...

A maize synthetic population was improved for resistance to the Mediterranean corn borer (MCB, Sesamia nonagrioides) while maintaining yield. The objectives of this research were to investigate whether yield and yield stability of the maize synthetic population named EPS12 were affected by selection for MCB resistance; also to determine which genot...

Ostrinia nubilalis (ECB) and Sesamia nonagrioides (MCB) are two maize stem borers which cause important losses in temperate maize production, but QTL analyses for corn borer resistance were mostly restricted to ECB resistance and maize materials genetically related (mapping populations derived from B73). Therefore, the objective of this work was to...

Phenolic esters have attracted considerable interest due to the potential they offer for peroxidase catalysed cross-linking of cell wall polysaccharides. Particularly, feruloyl residues undergo radical coupling reactions that result in cross-linking (intra-/intermolecular) between polysaccharides, between polysaccharides and lignin and, between pol...

In maize, the Mediterranean corn borer (MCB), Sesamia nonagrioides Lef, is the insect pest that causes the most significant yield losses in north-western Spain. A S1 recurrent selection program to improve resistance of EPS12 against MCB was evaluated previously. In the current study two experiments were conducted to determine if antibiosis and/or s...

The Mediterranean corn borer or pink stem borer (MCB, Sesamia nonagrioides Lefebvre) causes important yield losses as a consequence of stalk tunneling and direct kernel damage. B73 and Mo17 are the source of the most commercial valuable maize inbred lines in temperate zones, while the intermated B73 x Mo17 (IBM) population is an invaluable source f...

With 1 tableAbstractFusarium graminearum Schwabe is one of the predominant fungal species responsible for stalk rot of maize in Canada and many other countries. Adapted sources of resistance to this disease are scarce but recently a few have been identified. To evaluate the usefulness of these sources in a breeding programme to improve stalk rot re...

Recurrent selection has been reported as successful for improving maize resistance against corn borers. This study was conducted to determine if phenolics concentration in maize changes during recurrent selection to improve stalk resistance to the Mediterranean corn borer. Three cycles of selection [EPS12(S)C0, ESP12(S)C2, and EPS12(S)C3] from the...

Maize stem borers (Order: Lepidoptera) are one of most economically important insect pests, destroying 7% of the maize world crop annually. They belong to two Lepidotera families, Crambidae and Noctuidae. Every stage of the plant is susceptible of stem borer attack; however stem borers are characterized by spending the majority of their life cycle...

The relationship between phenolic compounds and maize pith resistance to Fusarium graminearum, the causal agent of Gibberella stalk rot, was investigated. The phenolic acid profiles in the stalks of six maize inbred lines of varying susceptibility were evaluated from silking to grain maturity. Four different fractions of phenolic compounds were ext...

The leaf sheaths of selected inbred lines of maize (Zea mays L.) with variable levels of stem resistance to the Mediterranean corn borer Sesamia nonagrioides (Lefèvbre) were evaluated for antibiotic effect on insect development. Phytochemical analyses of leaf sheaths were conducted for cell wall phenylpropanoid content to gain a better understandin...

The pink stem borer (Sesamia nonagrioides Lef.) is the main corn (Zea mays L.) pest in the Mediterranean area. Although, screening for resistance to this pest has been successful, the level of resistance shown by the most resistant varieties is not high. The objectives of the present work were: (i) the evaluation for pink stem borer resistance of t...

Fusarium moniliforme and Fusarium proliferatum are the most frequently isolated fungi from maize (Zea mays L.) in Spain. Both Fusarium species produce toxins potentially dangerous for animals and humans, the fumonisins being the most significant of those toxins. White maize is preferred for human consumption, and extra care should be taken to avoid...

The objective of this research was to evaluate the effect of four phenols previously identified at higher concentrations in maize resistant genotypes (p-coumaric acid, ferulic acid, p-hydroxybenzaldehyde and vanillin) on the growth and development of S. nonagrioides larvae. Three different concentrations of each phenolic compound and a mixture of t...

The stem borer Sesamia nonagrioides (Lefèbvre) is the most important insect pest that attacks maize, Zea mays L., in northwestern Spain. Host plant resistance to this borer was investigated in relation to the cell wall phenylpropanoids content in the pith. Eight inbred lines that differ in resistance were analyzed. Three major simple phenolic acids...

The stem borer Sesamia nonagrioides (Lefèbvre) is the most important insect pest of maize, Zea mays L., in northwestern Spain. Among the metabolites present in maize, phenolic compounds could play an important role in resistance. The objective of this work was to determine whether a relationship between phenols and the amount of resistance exists....

The pink stem borer, Sesamia nonagrioides (Lefebvre), is one of the most important insect pests of maize (Zea mays L.) in northwestern Spain. The objectives of this work were to evaluate, at different times during the growth of maize, structural traits related to the entry point and tissues on which larvae feed and to determine the relationship bet...