Water stress and cell wall polysaccharides in the apical root zone of wheat cultivars varying in drought tolerance

Leucci, Maria Rosaria; Lenucci, Marcello Salvatore; Piro, Gabriella; Dalessandro, Giuseppe

doi:10.1016/j.jplph.2007.09.006

Cited by 91 publications

(66 citation statements)

References 55 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The pectic side chains may also control CW porosity as has been suggested by Brummel (2006). Water stress increased the formation of pectic side chains in a drought-tolerant cultivar of wheat (Leucci et al 2008). Our finding of the PEG-induced reduction of CW pectin content in the root tips of common bean suggest that osmotic stress may interfere with the CW structure consequently resulting in the rearrangement of the wall polymers and thus affecting CW porosity .…”

Section: Cell-wall Porositymentioning

confidence: 71%

Interaction of aluminium and drought stress on root growth and crop yield on acid soils

2013

View full text Add to dashboard Cite

Background Aluminium (Al) toxicity and drought stress are two major constraints for crop production in the world, particularly in the tropics. The variation in rainfall distribution and longer dry spells in much of the tropics during the main growing period of crops are becoming increasingly important yield-limiting factors with the global climate change. As a result, crop genotypes that are tolerant of both drought and Al toxicity need to be developed. Scope The present review mainly focuses on the interaction of Al and drought on root development, crop growth and yield on acid soils. It summarizes evidence from our own studies and other published/related work, and provides novel insights into the breeding for the adaptation to these combined abiotic stresses. The primary symptom of Al phytotoxicity is the inhibition of root growth. The impeded root system will restrict the roots for exploring the acid subsoil to absorb water and nutrients which is particularly important under condition of low soil moisture in the surface soil under drought. Whereas drought primarily affects shoot growth, effects of phytotoxic Al on shoot growth are mostly secondary effects that are induced by Al affecting root growth and function, while under drought stress root growth may even be promoted. Much progress has recently been made in the understanding of the physiology and molecular biology of the interaction between Al toxicity and drought stress in common bean (Phaseolus vulgaris L.) in hydroponics and in an Al-toxic soil. Conclusions Crops growing on acid soils yield less than their potential because of the poorly developed root system that limits nutrient and water uptake. Breeding for drought resistance must be combined with Al resistance, to assure that drought resistance is expressed adequately in crops grown on soils with acid Al-toxic subsoils.

show abstract

Section: Cell-wall Porositymentioning

confidence: 71%

Interaction of aluminium and drought stress on root growth and crop yield on acid soils

2013

View full text Add to dashboard Cite

show abstract

“…Previous studies have reported that root growth under drought conditions can be promoted by cell-wall modulation of glucoronoxylan and rhamnogalacturonan side chains in cell-wall components (66,67). Correlating with these observations, genes expressed nearly exclusively in the root include many genes involved in cell-wall metabolism, such as multiple pectinesterases and polygalacturonases, several β-galactosidases, and a reversibly glycosylated protein involved in UDP-arabinofuranose production (68), the precursor for arabinan biosynthesis.…”

Section: Expression Divergence Correlates With Phenotypic Differencesmentioning

confidence: 85%

Comparative transcriptomics reveals patterns of selection in domesticated and wild tomato

Koenig

Jiménez‐Gómez²,

Kimura

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

338

268

View full text Add to dashboard Cite

Although applied over extremely short timescales, artificial selection has dramatically altered the form, physiology, and life history of cultivated plants. We have used RNAseq to define both gene sequence and expression divergence between cultivated tomato and five related wild species. Based on sequence differences, we detect footprints of positive selection in over 50 genes. We also document thousands of shifts in gene-expression level, many of which resulted from changes in selection pressure. These rapidly evolving genes are commonly associated with environmental response and stress tolerance. The importance of environmental inputs during evolution of gene expression is further highlighted by large-scale alteration of the light response coexpression network between wild and cultivated accessions. Human manipulation of the genome has heavily impacted the tomato transcriptome through directed admixture and by indirectly favoring nonsynonymous over synonymous substitutions. Taken together, our results shed light on the pervasive effects artificial and natural selection have had on the transcriptomes of tomato and its wild relatives.domestication | biotic stress | abiotic stress D omestication has long served as an important example of severe phenotypic divergence in response to selection. Darwin recognized the parallel between the processes of domestication and adaptation in the wild and used this analogy to emphasize the power of selection in generating phenotypic diversity (1). The genetic basis of domestication-associated phenotypes has been examined in several instances, most notably in maize, rice, tomato, and dogs (reviewed in refs. 2-5). The clear conclusion from these studies is that the rapid phenotypic divergence associated with domestication is often attributable to very few genetic loci (6). Improvements to DNA sequence technologies have allowed studies of the effect of domestication at the whole-genome level. Early population genetic analyses in maize found that very few genes (∼5%) show evidence of positive selection during domestication of maize (7), and recent work using whole-genome resequencing has found a similar proportion of the genome was under positive selection (8). Evidence for strong selective sweeps at a limited number of loci has also been found in rice and dog genomes (9). Together with the previous genetic mapping work, these studies support the model that relatively few mutations experienced extremely strong selection by humans during domestication.Although not the target of direct positive selection, the rest of the genome still experiences a dramatic shift in evolutionary pressures during domestication. Most characterized domestication events are associated with an extreme genetic bottleneck and alleviation of selective constraints in the original niche (10). These factors are predicted to increase the relative rate of nonsynonymous to synonymous (dN/dS) substitution, potentially resulting in the fixation of deleterious alleles (11). Previous studies comparing the distribution ...

show abstract

“…Cell wall modifications can provide an increased physical barrier against potential pathogens, while improving tolerance to drought and oxidative stress and maintaining turgor during osmotic stress (Piro et al, 2003;Pelloux et al, 2007;An et al, 2008;Leucci et al, 2008). The observed up-regulation of cell wall modification proteins in response to combined nematode and dehydration stress may therefore be a general defensive mechanism activated to confer broad-spectrum tolerance against multiple stresses.…”

Section: Cell Wall Modificationmentioning

confidence: 99%

Identification of Genes Involved in the Response of Arabidopsis to Simultaneous Biotic and Abiotic Stresses

2013

View full text Add to dashboard Cite

In field conditions, plants may experience numerous environmental stresses at any one time. Research suggests that the plant response to multiple stresses is different from that for individual stresses, producing nonadditive effects. In particular, the molecular signaling pathways controlling biotic and abiotic stress responses may interact and antagonize one another. The transcriptome response of Arabidopsis (Arabidopsis thaliana) to concurrent water deficit (abiotic stress) and infection with the plant-parasitic nematode Heterodera schachtii (biotic stress) was analyzed by microarray. A unique program of gene expression was activated in response to a combination of water deficit and nematode stress, with 50 specifically multiple-stress-regulated genes. Candidate genes with potential roles in controlling the response to multiple stresses were selected and functionally characterized. RAPID ALKALINIZATION FACTOR-LIKE8 (AtRALFL8) was induced in roots by joint stresses but conferred susceptibility to drought stress and nematode infection when overexpressed. Constitutively expressing plants had stunted root systems and extended root hairs. Plants may produce signal peptides such as AtRALFL8 to induce cell wall remodeling in response to multiple stresses. The methionine homeostasis gene METHIONINE GAMMA LYASE (AtMGL) was up-regulated by dual stress in leaves, conferring resistance to nematodes when overexpressed. It may regulate methionine metabolism under conditions of multiple stresses. AZELAIC ACID INDUCED1 (AZI1), involved in defense priming in systemic plant immunity, was down-regulated in leaves by joint stress and conferred drought susceptibility when overexpressed, potentially as part of abscisic acid-induced repression of pathogen response genes. The results highlight the complex nature of multiple stress responses and confirm the importance of studying plant stress factors in combination.

show abstract

Water stress and cell wall polysaccharides in the apical root zone of wheat cultivars varying in drought tolerance

Cited by 91 publications

References 55 publications

Interaction of aluminium and drought stress on root growth and crop yield on acid soils

Interaction of aluminium and drought stress on root growth and crop yield on acid soils

Comparative transcriptomics reveals patterns of selection in domesticated and wild tomato

Identification of Genes Involved in the Response of Arabidopsis to Simultaneous Biotic and Abiotic Stresses

Contact Info

Product

Resources

About