A robust sampling approach for identification and quantification of methyl jasmonate in leaf tissue of oilseed rape for analysis of early signaling in Sclerotinia sclerotiorum resistance.
BACKGROUND
Methyl jasmonate (MJA), which is a natrual hormonal regulator, is thought to be essential for the regulation of systemic defence responses. The information about MJA levels in plant tissues is helpful for the study of the disease resistance mechanism and genetically engineered cultivars with increased resistance. Therefore, the quantification of MJA levels in plant tissues by means of a sensitive and reliable method is of interest.


OBJECTIVE
Development of a film extraction method coupled with GC for determination of methyl jasmonate in leaf tissue of oilseed rape for analysis of early signalling in sclerotinia sclerotiorum resistance.


METHODS
A robust polydimethylsiloxane film was prepared and used for extraction of MJA in leaf tissues. By using in-solution extraction mode, optimum extraction efficiency was achieved with methanol-water (1 : 5, v/v) as extraction medium at 40 degrees C for 60 min.


RESULTS
Under the optimal conditions, a detection limit of 0.2 ng/mL was achieved. Excellent reproducibility was found over a linear range of 1-1000 ng/mL. MJA in leaves infected by sclerotinia sclerotiorum was determined, with the results showing that basal levels of MJA (15 ng/g) were present in noninfested controls, but increased to 313 ng/g 10 h after fungal attack.


CONCLUSIONS
The film extraction method is a simple, rapid and inexpensive sampling technique for determination of endogenous MJA in plant tissues that can be applied to most plants.
Wei
Fang
F
Ministry of Agriculture Key Laboratory of Oil Crops Biology, Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan, Hubei 430062, People's Republic of China.
Cheng
Ji-hua
JH
Liu
Sheng-yi
SY
Huang
Jun-yan
JY
Wang
Zhan
Z
Dong
Xu-yan
XY
Li
Ping-ping
PP
Kong
Fan-pi
FP
Wu
Yu
Y
Li
Yan-hua
YH
Feng
Yu-qi
YQ
Chen
Hong
H
D000085:Acetates / Q000032:analysis* / Q000302:isolation & purification; D001203:Ascomycota / Q000502:physiology; D029741:Brassica rapa / Q000737:chemistry* / Q000382:microbiology; D002849:Chromatography, Gas / Q000379:methods; D003517:Cyclopentanes / Q000032:analysis* / Q000302:isolation & purification; D054884:Host-Pathogen Interactions; D007113:Immunity, Innate; D000432:Methanol / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D054883:Oxylipins / Q000032:analysis* / Q000302:isolation & purification; D010935:Plant Diseases / Q000382:microbiology; D010936:Plant Extracts / Q000032:analysis / Q000302:isolation & purification; D018515:Plant Leaves / Q000737:chemistry*; D015203:Reproducibility of Results; D015398:Signal Transduction / Q000502:physiology; D013696:Temperature
D000085:Acetates; D003517:Cyclopentanes; D054883:Oxylipins; D010936:Plant Extracts; C072239:methyl jasmonate; D000432:Methanol