Foo, E and Ross, JJ and Jones, WT and Reid, JB, Plant hormones in arbuscular mycorrhizal symbioses: An emerging role for gibberellins, Annals of Botany, 111, (5) pp. 769-779. ISSN 0305-7364 (2013) [Refereed Article]
Copyright 2013 The Author.
Background and Aims: Arbuscular mycorrhizal symbioses are important for nutrient acquisition in .80% of terrestrial plants. Recently there have been major breakthroughs in understanding the signals that regulate colonization by the fungus, but the roles of the known plant hormones are still emerging. Here our understanding of the roles of abscisic acid, ethylene, auxin, strigolactones, salicylic acid and jasmonic acid is discussed, and the roles of gibberellins and brassinosteroids examined.
Methods: Pea mutants deficient in gibberellins, DELLA proteins and brassinosteroids are used to determine whether fungal colonization is altered by the level of these hormones or signalling compounds. Expression of genes activated during mycorrhizal colonization is also monitored.
Key Results: Arbuscular mycorrhizal colonization of pea roots is substantially increased in gibberellin-deficient na-1 mutants compared with wild-type plants. This is reversed by application of GA3. Mutant la cry-s, which lacks gibberellin signalling DELLA proteins, shows reduced colonization. These changes were parallelled by changes in the expression of genes associated with mycorrhizal colonization. The brassinosteroid-deficient lkb mutant showed no change in colonization.
Conclusions: Biologically active gibberellins suppress arbuscule formation in pea roots, and DELLA proteins are essential for this response, indicating that this role occurs within the root cells.
|Item Type:||Refereed Article|
|Keywords:||arbuscular mycorrhizae, symbiosis, gibberellin, brassinosteroid, plant hormones, strigolactones, auxin, abscisic acid, ethylene, jasmonic acid, salicylic acid.|
|Research Division:||Biological Sciences|
|Research Group:||Plant biology|
|Research Field:||Plant physiology|
|Objective Division:||Plant Production and Plant Primary Products|
|Objective Group:||Environmentally sustainable plant production|
|Objective Field:||Environmentally sustainable plant production not elsewhere classified|
|UTAS Author:||Foo, E (Associate Professor Eloise Foo)|
|UTAS Author:||Ross, JJ (Associate Professor John Ross)|
|UTAS Author:||Reid, JB (Professor Jim Reid)|
|Funding Support:||Australian Research Council (DP0772348)|
|Web of Science® Times Cited:||155|
|Deposited By:||Plant Science|
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