Role of gibberellins during arbuscular mycorrhizal formation in tomato: new insights revealed by endogenous quantification and genetic analysis of their metabolism in mycorrhizal roots

0446757 - ÚEB 2016 RIV DK eng J - Journal Article
Martin-Rodriguez, J.A. - Ocampo, J.A. - Molinero-Rosales, N. - Tarkowská, Danuše - Ruiz-Rivero, O. - Garcia-Garrido, J.M.
Role of gibberellins during arbuscular mycorrhizal formation in tomato: new insights revealed by endogenous quantification and genetic analysis of their metabolism in mycorrhizal roots.
Physiologia Plantarum. Roč. 154, č. 1 (2015), s. 66-81. ISSN 0031-9317. E-ISSN 1399-3054
R&D Projects: GA MŠMT LK21306
Grant - others:GA MŠk(CZ) ED0007/01/01
Program: ED
Institutional support: RVO:61389030
Keywords : GLOMUS-INTRARADICES * FRUIT-SET * MEDICAGO-TRUNCATULA
Subject RIV: EF - Botanics
Impact factor: 3.520, year: 2015

Gibberellins (GAs) are key regulators of plant growth and development and recent studies suggest also a role during arbuscular mycorrhizal (AM) formation. Here, complementary approaches have been used to obtain a clearer picture that correlates AM fungal development inside roots with GA metabolism. An extensive analysis of genes associated with GA metabolism as well as a quantification of GA content in roots was made. Application of GA(3) and its biosynthesis inhibitor prohexadione calcium (PrCa) combined with a GA-constitutive response mutant (procera) were used to determine whether fungal colonization is altered by the level of these hormones or by changes in the GA-signaling pathway. The increased levels of specific GAs from the 13-hydroxylation pathway in mycorrhizal roots correlate closely with the increased expression of genes coding enzymes from the GA biosynthetic trail. The imbalance of GAs in tomato roots caused by exogenous applications of GA(3) or PrCa affects arbuscules in both negative and positive ways, respectively. In addition, procera plants were adversely affected by the mycorrhization process. Our findings demonstrate that an imbalance in favor of an increased amount of GAs negatively affects the frequency of mycorrhization and particularly the arbuscular abundance in tomato mycorrhizal roots and the results point out that AM formation is associated with a change in the 13-hydroxylation pathway of GAs.
Permanent Link: http://hdl.handle.net/11104/0248716