Record ID No. |
1967 |
Author(s) |
Rapparini F., Llusia J., Penuelas J , 2008 |
Affiliation |
IBIMET CNR, Biometeorol Inst, Via P Gobetti 101, I-40129 Bologna, ITALY |
Title |
Effect of arbuscular mycorrhizal (AM) colonization on terpene emission and content of Artemisia annua L |
Source. Vol.(no):Page |
Plant Biology.10(1):108-122p. |
Categories |
Arbuscular Mycorrhiza |
Subjects |
Biochemistry |
Sub-subjects |
Miscellaneous |
Organism |
n.a. |
Country |
ITALY,Europe |
Abstracts |
Plant roots interact with a wide variety of rhizospheric microorganisms,
including bacteria and the symbiontic arbuscular mycorrhizal (AM) fungi. The mycorrhizal
symbiosis represents a series of complex feedbacks between plant and fungus regulated by their
physiology and nutrition. Despite the widespread distribution and ecological significance of AM
symbiosis, little is known about the potential of AM fungi to affect plant VOC metabolism. The
purpose of this study was to investigate whether colonization of plant roots by AM fungi and
associated soil microorganisms affects VOC emission and content of Artemisia annua L. Plants
(Asteraceae). Two inoculum types were evaluated: one consisted of only an arbuscular mycorrhizal
(AM) fungus species (Glomus spp.), and the other was a mixture of different Glomus species and
associated soil bacteria. Inoculated plants were compared with non-inoculated plants and with
plants supplemented with extra phosphorus (P) to obtain plants of the same size as mycorrhizal
plants, thus excluding potentially-confounding mycorrhizal effects on shoot growth. VOC emissions
of Artemisia annua plants were analyzed by leaf cuvette sampling followed by off-line
measurements with pre-concentration and gas chromatography mass spectrometry (GC-MS).
Measurements of CO2 and H2O exchanges were conducted simultaneously. Several volatile
monoterpenes were identified and characterized from leaf emissions of Artemisia annua L. By GC-MS
analysis. The main components identified belong to different monoterpene structures:
alpha-pinene, beta-pinene, camphor, 1,8-cineole, limonene, and artemisia ketone. A good
correlation between monoterpene leaf concentration and leaf emission was found. Leaf extracts
included also several sesquiterpenes. Total terpene content and emission was not affected by AM
inoculation with or without bacteria, while emission of limonene and artemisia ketone was
stimulated by this treatment. No differences were found among treatments for single monoterpene
content, while accumulation of specific sesquiterpenes in leaves was altered in mycorrhizal
plants compared to control plants. Growth conditions seemed to have mainly contributed to the
outcome of the symbiosis and influenced the magnitude of the plant response. These results
highlight the importance of considering the below-ground interaction between plant and soil for
estimating VOC emission rates and their ecological role at multitrophic levels.
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