Khalloufi Mouna, Martínez-Andújar Cristina, Lachaâl Mokhtar, Karray-Bouraoui Najoua, Pérez-Alfocea Francisco, Albacete Alfonso
Department of Plant Nutrition, CEBAS-CSIC, Campus Universitario de Espinardo, 30100 Murcia, Spain; Unité de Physiologie et Biochimie de la Réponse des Plantes aux Contraintes Abiotiques, Faculté des Sciences de Tunis, Campus Universitaire, 2092 Tunis El Manar, Tunisia.
Department of Plant Nutrition, CEBAS-CSIC, Campus Universitario de Espinardo, 30100 Murcia, Spain.
J Plant Physiol. 2017 Jul;214:134-144. doi: 10.1016/j.jplph.2017.04.012. Epub 2017 Apr 28.
The agriculture industry is frequently affected by various abiotic stresses limiting plant productivity. To decrease the negative effect of salinity and improve growth performance, some strategies have been used, such as exogenous application of plant growth regulators (i.e. gibberellic acid, GA), or arbuscular mycorrhizal fungi (AMF) inoculation. To gain insights about the cross-talk effect of exogenous GA application and AMF inoculation on growth under salinity conditions, tomato plants (Solanum lycopersicum, cv. TT-115) were inoculated or not with the AMF Rhizophagus irregularis and exposed to different treatments during two weeks: 0M GA+0mM NaCl, 10M GA+0mM NaCl, 0M GA+100mM NaCl and 10M GA+100mM NaCl. Results have revealed that AMF inoculation or GA application alone, but especially their interaction, resulted in growth improvement under salinity conditions. The growth improvement observed in AMF-inoculated tomato plants under salinity conditions was mainly associated to ionic factors (higherK concentration and K/Na ratio) while the alleviating effect of GA application and its interaction with AMF appear to be due to changes in the hormonal balance. Foliar GA application was found to increase the active gibberellins (GAs), resulting in a positive correlation between GA and the growth-related parameters. Furthermore, cytokinins, indoleacetic acid and abscisic acid concentrations increased in AMF inoculated or GA treated plants but, notably, in AMF plants treated with GA, which showed improved growth under salinity conditions. This suggests that there is an interactive positive effect between GAs and AMF which alleviates growth impairment under salinity conditions by modifying the hormonal balance of the plant.
农业产业经常受到各种非生物胁迫的影响，这些胁迫限制了植物的生产力。为了降低盐度的负面影响并改善生长性能，人们采用了一些策略，例如外源施用植物生长调节剂（即赤霉素，GA），或接种丛枝菌根真菌（AMF）。为了深入了解外源GA施用和AMF接种在盐度条件下对生长的相互作用影响，对番茄植株（番茄，品种TT-115）接种或不接种AMF不规则球囊霉，并在两周内进行不同处理：0μM GA + 0mM NaCl、10μM GA + 0mM NaCl、0μM GA + 100mM NaCl和10μM GA + 100mM NaCl。结果表明，单独接种AMF或施用GA，但特别是它们的相互作用，导致在盐度条件下生长得到改善。在盐度条件下，接种AMF的番茄植株观察到的生长改善主要与离子因素（较高的钾浓度和钾/钠比率）有关，而GA施用及其与AMF的相互作用的缓解作用似乎是由于激素平衡的变化。发现叶面施用GA会增加活性赤霉素（GAs），导致GA与生长相关参数之间呈正相关。此外，接种AMF或GA处理的植株中细胞分裂素、吲哚乙酸和脱落酸浓度增加，但值得注意的是，在GA处理的AMF植株中，其在盐度条件下生长得到改善。这表明GA和AMF之间存在交互正效应，通过改变植物的激素平衡来缓解盐度条件下的生长障碍。
