Agriculture Reference
In-Depth Information
growth and development. Salicylic acid is considered as a plant hormone
because of its role in regulating some aspects of disease resistance in
plants (Raskin, 1992). More recently, the involvement of SA as a signal
molecule in systemic acquired resistance associated with the production
of pathogenesis-related proteins has been extensively shown (Beckers and
Spoel, 2006). Moreover, dietary salicylates from fruit and vegetables are
described as bioactive compounds with health care potential (Hooper and
Cassidy, 2006), and considered as generally recognized as safe (GRAS).
There are several reports on beneficial effects of SA treatment in fruits.
During kiwifruit ripening, the pattern of decrease in endogenous SA levels
was related to accelerated softening, while the application of acetylsali-
cylic acid (ASA, a derivative of SA) slowed down the softening rate of
kiwifruit by inhibiting ethylene production and maintaining higher endog-
enous SA levels (Zhang et al., 2003). On the other hand, SA application
either preharvest (Yao and Tian, 2005) or postharvest reduced fungal de-
cay in sweet cherry through induction of the defense resistance system
(Chan and Tian, 2006) and stimulation of antioxidant enzymes (Xu and
Tian, 2008). In addition, in chilling injury sensitive fruit, pretreatment
with SA reduced chilling injury symptoms in peaches (Wang et al., 2006)
and pomegranates (Sayyari et al., 2009).
16.4
METHYL JASMONATE (MEJA)
Jasmonates are a class of endogenous plant growth regulators that have
unique and potentially useful properties that affect plant growth and devel-
opment in response to environmental stresses. Methyl Jasmonate (MeJA)
was discovered in 1962 as a sweet-smelling compound in
Jasminium gran-
diflorum
flower extracts (Demole et al., 1962). The main effects of MeJA
in post harvest management of fruits are- control postharvest disease and
decay of fruits, alleviate chilling injury, regulation of fruit ripening and se-
nescence, fruit quality maintenance, development of color and aroma vola-
tiles, etc. Zhang et al. (2006) reported that MeJA can be effectively used to
control gray mold rot in strawberry caused by
Botrytis cinerea
and it also
enhances disease resistance in peach (Jin et al., 2009), loquat (Cao et al.,
2008) and raspberries (Chanjirakul et al., 2006). Potential uses of MeJA in
alleviating chilling injury of fruits have also been studied. In most of the
experiments, loquat and pomegranate fruits treated with MeJA, exhibited
