Arbuscular mycorrhizal could improve drought tolerance in lettuce and tomato plants. - GreenMedInfo Summary
Arbuscular mycorrhizal symbiosis induces strigolactone biosynthesis under drought and improves drought tolerance in lettuce and tomato.
Plant Cell Environ. 2015 Aug 25. Epub 2015 Aug 25. PMID: 26305264
Juan Manuel Ruiz-Lozano
Arbuscular mycorrhizal (AM) symbiosis alleviates drought stress in plants. However the intimate mechanisms involved, as well as its effect on the production of signalling molecules associated to the host plant-AM fungus interaction remains largely unknown. In the present work, the effects of drought on lettuce and tomato plant performance and hormone levels were investigated in non-AM and AM plants. Three different water regimes were applied and their effects analysed over time. AM plants showed an improved growth rate and efficiency of photosystem II than non-AM plants under drought from very early stages of plant colonization. The levels of the phytohormone abscisic acid, as well as the expression of the corresponding marker genes, were influenced by drought stress in non-AM and AM plants. The levels of strigolactones and the expression of corresponding marker genes were affected by both AM symbiosis and drought. The results suggest that AM symbiosis alleviates drought stress by altering the hormonal profiles and affecting plant physiology in the host plant. In addition, a correlation between AM root colonization, strigolactone levels and drought severity is shown, suggesting that under these unfavourable conditions plants might increase strigolactone production in order to promote symbiosis establishment to cope with the stress.