- CHILLING INJURY IN TOMATO FRUIT 251
attack, tissues produce and deposit lignin and suberin in their wall as
a protective barrier to counterattack that stress (Eckert 1978). Temper-
ature and humidity are important factors influencing suberization dur-
ing postharvest storage. Maintaining fruit at low temperatures below the
chilling threshold, or for too long, could prevent suberin production by
cells surrounding the wound and ultimately facilitate infection of an
intact host (Barkai-Golan 2001).
Links between ethylene and decay incidence have been proposed.
However, ethylene has an ambiguous effect on decay development and
the mechanism of ethylene involvement in enhancing tissue suscep-
tibility to pathogens is a matter of debate (Porat et al. 1999). Ethy-
lene application stimulatedAlternariaandBotrytisinfection in tomato
(Segall et al. 1974; Barkai-Golan and Lavy-Meir 1989) andBotrytis
in strawberry (El-Kazzaz et al. 1983). Even concentrations of ethy-
lene lower than those produced during ripening of climacteric fruit
are capable of stimulating pathogen hyphal germination and elonga-
tion (Flaishman and Kolattukudy 1994). Ethylene promotes fruit ripen-
ing and ripening fruit is characterized by an increase in susceptibility
to necrotrophic pathogens (Prusky 1996; Giovannoni 2001). Inhibiting
ethylene action by potassium permanganate or 1-MCP reduces decay
susceptibility (Wills and Kim 1995; Su and Gubler 2012).
However, some researchers reported that ethylene does not affect dis-
ease development, and may even enhance host resistance to pathogen
attack by activating plant defense-related processes including produc-
tion of phytoalexins (Fan et al. 2000) or pathogenesis-related proteins
(Ding et al. 2002). Geeson et al. (1986) found that tomatoes stored
under controlled atmospheres showed increased susceptibility toBotry-
tiswith a decrease in supply of exogenous ethylene and suggested
that 1–3μLL−^1 of ethylene was required for decay control. Similarly,
enhanced resistance to decay by ethylene was reported for sweet pota-
toes (Stahmann et al. 1966) and tangerines (Brown and Barmore 1977).
D ́ıaz et al. (2002) suggested that ethylene perception is required for
increased resistance of tomato leaves toBotrytis, as inhibition of ethy-
lene response by 1-MCP resulted in increased decay susceptibility.
The inconsistent relationship between ethylene and decay suscepti-
bility during storage can be clarified, at least in part, by studies that
involved 1-MCP. The association of 1-MCP and tomato decay has also
been reported previously with mixed results. Guillen et al. (2006) found ́
that 1-MCP was highly effective in reducing decay in many tomato
cultivars harvested at advanced maturity stages (breaker or ripe) and
stored at 10◦C, and Su and Gubler (2012) supported this where they
found reduced decay in 1-MCP treated mature-green tomatoes stored