title: Root-targeted biotechnology to mediate hormonal signalling and improve crop stress tolerance.
abstract: Since plant root systems capture both water and nutrients essential for the formation of crop yield, there has been renewed biotechnological focus on root system improvement. Although water and nutrient uptake can be facilitated by membrane proteins known as aquaporins and nutrient transporters, respectively, there is a little evidence that root-localised overexpression of these proteins improves plant growth or stress tolerance. Recent work suggests that the major classes of phytohormones are involved not only in regulating aquaporin and nutrient transporter expression and activity, but also in sculpting root system architecture. Root-specific expression of plant and bacterial phytohormone-related genes, using either root-specific or root-inducible promoters or grafting non-transformed plants onto constitutive hormone producing rootstocks, has examined the role of root hormone production in mediating crop stress tolerance. Root-specific traits such as root system architecture, sensing of edaphic stress and root-to-shoot communication can be exploited to improve resource (water and nutrients) capture and plant development under resource-limited conditions. Thus, root system engineering provides new opportunities to maintain sustainable crop production under changing environmental conditions.
authors.affiliation: Groupe de Recherche en Physiologie végétale, Earth and Life Institute (ELI-A), Université catholique de Louvain, 1348, Louvain-la-Neuve, Belgium. michel.ghanem@uclouvain.be
authors.forename: Michel Edmond
authors.initials: ME
authors.lastname: Ghanem
authors.forename: Imène
authors.initials: I
authors.lastname: Hichri
authors.forename: Ann C
authors.initials: AC
authors.lastname: Smigocki
authors.forename: Alfonso
authors.initials: A
authors.lastname: Albacete
authors.forename: Marie-Laure
authors.initials: ML
authors.lastname: Fauconnier
authors.forename: Eugene
authors.initials: E
authors.lastname: Diatloff
authors.forename: Cristina
authors.initials: C
authors.lastname: Martinez-Andujar
authors.forename: Stanley
authors.initials: S
authors.lastname: Lutts
authors.forename: Ian C
authors.initials: IC
authors.lastname: Dodd
authors.forename: Francisco
authors.initials: F
authors.lastname: Pérez-Alfocea
mesh_terms: D000222:Adaptation, Physiological; D020346:Aquaporins / Q000235:genetics / Q000378:metabolism; D001692:Biological Transport; D001709:Biotechnology / Q000379:methods*; D018556:Crops, Agricultural / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D005818:Genetic Engineering / Q000379:methods; D010937:Plant Growth Regulators / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics; D015398:Signal Transduction; D013312:Stress, Physiological / Q000235:genetics; D014867:Water / Q000378:metabolism
chemical_list: D020346:Aquaporins; D010937:Plant Growth Regulators; D010940:Plant Proteins; D014867:Water