02869nas a2200253   4500008004100000022001400041245012500055210006900180260009000249300001200339490000700351520190100358653001802259653002402277653002102301653003402322653001902356653001102375100001802386700002102404700003702425700002102462856013202483       2015                        eng d  a0885-576500aRole of methyl jasmonate in the expression of mycorrhizal induced resistance against Fusarium oxysporum in tomato plants0 aRole of methyl jasmonate in the expression of mycorrhizal induce  a24-28 OVAL RD, LONDON NW1 7DX, ENGLANDbACADEMIC PRESS LTD- ELSEVIER SCIENCE LTDcOCT  a139-1450 v923 a<p>Arbuscular mycorrhiza (AM) colonization led to a decrease in the severity of fusarium wilt disease caused by Fusarium oxysporum f. sp. lycopersici in tomato plants. The involvement of two plant defense hormones, namely methyl jasmonate (MeJA) and salicylic acid (SA), in the expression of mycorrhiza induced resistance (MIR) against this vascular pathogen was studied in the AM colonized and non-colonized (controls) plants. Activity of lipoxygenase (LOX), which plays a role in jasmonic acid (JA) biosynthesis, as well as levels of methyl jasmonate (MeJA) increased in AM colonized plants as compared to controls, but did not show any further changes in response to F. oxysporum inoculation. On the other hand, activity of phenylalanine ammonia lyase (PAL), which is an enzyme from salicylic acid (SA) biosynthetic pathway, as well as SA levels, increased in both controls and AM colonized plants in response to application of F. oxysporum spores. Hence the JA and not the SA signalling pathway appeared to play a role in the expression of MIR against this vascular pathogen. The resistance observed in AM colonized plants was completely compromised when plants were treated with the JA biosynthesis inhibitor salicylhydroxamic acid (SHAM). This confirmed that the AM-induced increase in JA levels was involved in the expression of resistance toward F. oxysporum. The SA response gene pathogenesis-related 1 (PR1) showed an increased expression in response to F. oxysporum infection in SHAM treated AM colonized plants as compared to plants that were not treated with this JA inhibitor. This suggested the possibility that JA inhibited SA responses, at least in the roots. AM colonization therefore appeared to prime plants for improved tolerance against the vascular pathogen F. oxysporum, which was mediated through the JA signalling pathway. (C) 2015 Elsevier Ltd. All rights reserved.</p>10aFusarium wilt10aGlomus fasciculatum10aMethyl jasmonate10aMycorrhiza induced resistance10aSalicylic acid10aTomato1 aNair, Aswathy1 aKolet, Swati, P.1 aThulasiram, Hirekodathakallu, V.1 aBhargava, Sujata  uhttps://library.ncl.res.in/content/role-methyl-jasmonate-expression-mycorrhizal-induced-resistance-against-fusarium-oxysporum-0