a b s t r a c t
Chemical
fungicides are widely used for the control of preharvest fungal
diseases. However, they may induce changes in quality characteristics,
accelerating or delaying senescence. The effects of preharvest
application of fenhexamid, or pyraclostrobin + boscalid, on tomato fruit
(Solanum lycopersicum L.) cvs. Raf, Amadeo and Nereida, were compared
to untreated fruit at harvest and during storage. The impact of
fungicides in Nereida tomatoes was notable as fruit treated with
fenhexamid displayed increased in maturity index, weight loss and the
accumulation of vitamin C compared with fruit treated with
pyraclostrobin + boscalid. Preharvest application of pyraclostrobin +
boscalid delayed ripening and senescence of long life Nereida tomatoes
and therefore affected postharvest quality. Application of
pyraclostrobin + boscalid to Nereida tomatoes reduced weight loss, did
not modify fruit color, sugar content or acidity, and did not induce the
accumulation of lycopene and phenolic compounds. The same preharvest
treatments did not affect the main quality attributes in Raf and Amadeo
cultivars, short and short-medium life tomatoes, respectively. Untreated
fruit had higher contents of total and individual phenolic compounds
such as naringenin and naringenin chalcone as they may act as plant
defence secondary metabolites. Preharvest application of pyraclostrobin +
boscalid, as well as having a roadspectrum activity for fruit disease
control, may also be beneficial in prolonging the postharvest life of
long life cultivars such as Nereida tomatoes without negatively
affecting quality attributes. The results of this study suggest that
different fungicides may have different potential for the preservation
of tomato quality, but the responses depend on the cultivar.
تاثیر کاربرد قبل از برداشت قارچ کش ها بر کیفیت پس از برداشت گیاه گوجه فرنگی (Solanum lycopersicum L.)
چکیده