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Abstract
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Elicitors, irrigation regimes and harvest times
influence the content, yield and compound of the essential
oil (EO) in Salvia officinalis (sage), through changes in bio-
mass dynamics and biosynthetic pathways. A two-year field
experiment was conducted to determine if foliar application
of putrescine under optimum and deficit stress conditions
would favorably affect EO yield, content and profile of sage
harvested in spring and summer. The response of dry weight,
EO yield and content, myrcene and borneol concentrations
to irrigation regime and putrescine concentration can be
expressed by a quadratic model. The maximum dry weight
(182.63 g m −2 ) and EO yield (1.68 g m −2 ) were predicted
under irrigation regimes of 9.06% and 27.75% available
soil water depletion (ASWD), respectively. The highest EO
content (1.05%) was predicted under 3.04 mM of putres-
cine. Based on results obtained from GC/MS analyses, 25
compounds (mostly monoterpenes) were identified in the
EO of sage. Among EO compounds, α-thujone (54.08%),
1, 8-cineole (17.87%), pinocarvone (14.30%), β-thujone
(7.97%) and camphor (8.76%) in turn were the most abun-
dant. The concentration of myrcene was higher in spring
than summer under the irrigation regimes of 60% and 80%
ASWD. The myrcene concentration reached its maximum
(4.53%) under the irrigation regime of 86.5% ASWD. The
irrigation regimes of 48.03% and 45.6% ASWD caused the
highest borneol concentrations of 1.47% and 1.41% by appli-
cation of 1.5 mM and 2.25 mM putrescine, respectively. All
treatments tested on sage, particularly harvest time, can play
an important role in the improvement of EO quality and
quantity. Averaged over both years, the irrigation regime
of nearly 30% ASWD resulted in the highest EO yield har-
vested with greater quantity and better quality in summer.
The EO content and quality changed slightly with the appli-
cation of putrescine, without significant effect on yield
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