Priming of Anti-Herbivore Defense in Tomato by Arbuscular Mycorrhizal Fungus and Involvement of the Jasmonate Pathway
- 1.4k Downloads
Mycorrhizas play a vital role in soil fertility, plant nutrition, and resistance to environmental stresses. However, mycorrhizal effects on plant resistance to herbivorous insects and the related mechanisms are poorly understood. This study evaluated effects of root colonization of tomato (Solanum lycopersicum Mill.) by arbuscular mycorrhizal fungi (AMF) Glomus mosseae on plant defense responses against a chewing caterpillar Helicoverpa arimigera. Mycorrhizal inoculation negatively affected larval performance. Real time RT-PCR analyses showed that mycorrhizal inoculation itself did not induce transcripts of most genes tested. However, insect feeding on AMF pre-inoculated plants resulted in much stronger defense response induction of four defense-related genes LOXD, AOC, PI-I, and PI-II in the leaves of tomato plants relative to non-inoculated plants. Four tomato genotypes: a wild-type (WT) plant, a jasmonic acid (JA) biosynthesis mutant (spr2), a JA-signaling perception mutant (jai1), and a JA-overexpressing 35S::PS plant were used to determine the role of the JA pathway in AMF-primed defense. Insect feeding on mycorrhizal 35S::PS plants led to higher induction of defense-related genes relative to WT plants. However, insect feeding on mycorrhizal spr2 and jai1 mutant plants did not induce transcripts of these genes. Bioassays showed that mycorrhizal inoculation on spr2 and jai1 mutants did not change plant resistance against H. arimigera. These results indicates that mycorrhizal colonization could prime systemic defense responses in tomato upon herbivore attack, and that the JA pathway is involved in defense priming by AMF.
KeywordsDefense priming Arbuscular mycorrhizal fungus Induced defense Jasmonate pathway Tomato Glomus mosseae Helicoverpa arimigera
This research was supported by the National 973 Program of China (2011CB100400), National Natural Science Foundation of China (31070388, 31028018, 31100286), Guangdong Province Universities and Colleges Pearl River Scholar Funded Scheme (2010), Guangdong Natural Science Foundation of China (S2011040004336), China Postdoctoral Science Foundation (201104341, 20100480762), and Ph.D. Foundation of the Ministry of Education of China (20104404110004).
- Christensen SA, Nemchenko A, Borrego E, Murray I, Sobhy IS, Bosak L, Deblasio S, Erb M, Robert CA, Vaughn KA, Herrfurth C, Tumlinson J, Feussner I, Jackson D, Turlings TC, Engelberth J, Nansen C, Meeley R, Kolomiets MV (2013) The maize lipoxygenase, ZmLOX10, mediates green leaf volatile, jasmonate and herbivore-induced plant volatile production for defense against insect attack. Plant J 74:59–73PubMedCrossRefGoogle Scholar
- Gange AC (1996) Reduction in vine weevil larval growth by mycorrhizal fungi. Mitt Biol Bund Forst 316:56–60Google Scholar
- Kiefer E, Heller W, Ernst D (2000) A simple and efficient protocol for isolation of functional RNA from plant tissues rich in secondary metabolites. Plant Mol Biol Rep 18:33–39Google Scholar
- León-Morcillo RJ, Angel J, Martín-Rodríguez, Vierheilig H, Ocampo JA, García-Garrido JM (2012) Late activation of the 9-oxylipin pathway during arbuscular mycorrhiza formation in tomato and its regulation by jasmonate signalling. J Exp Bot 63:545–3558Google Scholar
- Li CY, Liu GH, Xu CC, Lee GI, Bauer P, Ling HQ, Ganal MW, Howe GA (2003) The tomato suppressor of prosystemin-mediated responses 2 gene encodes a fatty acid desaturase required for the biosynthesis of jasmonic acid and the production of a systemic wound signal for defense gene expression. Plant Cell 15:1646–1661PubMedCrossRefGoogle Scholar
- Pozo MJ, Verhage A, García-Andrade J, García JM, Azcon-Aguilar C (2009) Priming plant defence against pathogens by arbuscular mycorrhizal fungi. In: Azcón-Aguilar C, Gianinazzi S, Barea JM, Gianinazzi-Pearson V (eds) Mycorrhizas - functional processes and ecological impact. Springer- Verlag, Berlin Heidelberg, pp 123–135CrossRefGoogle Scholar
- Schaller F, Schaller A, Stintz A (2005) Biosynthesis and metabolism of jasmonates. J Plant Growth Regul 23:179–199Google Scholar
- Smith SE, Read DJ (2008) Mycorrhizal symbiosis. Academic, LondonGoogle Scholar
- Song YY, Wang RL, Wei XC, Lu YJ, Wu GZ, Su YJ, Zeng RS (2011) Mechanism of tomato plants enhanced disease resistance against early blight primed by arbuscular mycorrhizal fungus Glomus versiforme. Chin J Appl Ecol 22:2316–2324 (in Chinese)Google Scholar
- van der Heijden MGA, Klironomos JN, Ursic M, Moutoglis P, Streitwolf-Engel R, Boller T, Wiemken A, Sanders IR (1998) Mycorrhizal fungal diversity determines plant biodiversity, ecosystem variability and productivity. Nature 365:69–72Google Scholar
- Waldbauer GP, Cohen RW, Friedman S (1984) An improved procedure for laboratory rearing of the corn earworm, Heliothis zea (Lepidoptera: Noctuidae). Great Lakes Entomol 17:113–118Google Scholar