LIBRO-CONGRESO-CITRUS

S21
pallet and in the fruits) 40 digital probes were used. In order to optimize air circulation across fruits boxes, an
innovative package (with a new designed vented surface) was compared to the standard boxes. Results show
that the mean temperature difference between the probes placed in the head space was less than 0,5°C. Graphic
peaks showed the on/off cycle of the automatic defrosting system. The probes placed on the container floor
demonstrated a good result in terms of temperature homogeneity, but the temperature reached a minimum
level of about -0,8°C which could be considered too low for citrus fruits storage. The innovative vented boxes
allowed a more rapid cooling and a more accurate temperature control.
S21P07
Application of 3,5,6-TPA under commercial conditions to control calyx senescence associated to
degreening treatment
Tormo D. 1 , Conesa E. 1 , Sdiri S. 2 , Navarro P. 2 , and Salvador A. 2
1 Fomesa Fruitech (FOMESA), Technical Department, Spain; and 2 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de
Tecnología Postcosecha, Spain. econesa.fruitech@fomesa.net
Postharvest degreening treatment with exogenous ethylene application is widely used in Mediterranean
growth area to improve the external coloration of the early-season citrus varieties in which internal maturity
is achieved when the peel is still green. Nevertheless this treatment can induce physiological disorders overall
related to calyx senescence. In previous studies has been reported that the application of 3,5,6-trichloro-2pyridyloxyacetic
acid (TPA) reduces calyx senescence associated to ethylene exposure. However it is important
to know the effect of this auxin under commercial industrial conditions.
The purpose of this study was to evaluate the effect of postharvest application of TPA on reduction disorders
associated to degreening in clementines (‘Clemenpons’ and ‘Clemenules’) in different commercial postharvest
applications (in drencher and on-line). The application of TPA in drencher very significantly reduces the
disorders of calyx senescence associated to degreening treatment in clementines, recommending 40 ppm
of TPA as the most effective dose. The application of TPA ‘on-line’ treatments were effective on reduction
of calyx disorders, obtaining the best results with 100 ppm of TPA; nevertheless in the trials carried out
clementines exhibited low susceptibility to calyx disorders after degreening process. The results suggest that
this auxin could be a good option to control disorders of citrus fruit during degreening treatment.
S21P08
Postharvest behavior of new mandarins cultivars obtained at the IVIA
Sdiri S. 1 , Navarro P. 1 , Cuenca J. 2 , Pardo J. 3 , and Salvador A. 1
1 Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Tecnología Postcosecha, Spain; 2 Instituto Valenciano de
Investigaciones Agrarias (IVIA), Centro de Protección Vegetal y Biotecnología, Spain; 3 Instituto Valenciano de Investigaciones Agrarias
(IVIA), Centro de Citricultura y Producción Vegetal, Spain. salvador_ale@gva.es
A triploid breeding program has been carried out in Plant Protection and Biotechnology Center in the Instituto
Valenciano de Investigaciones Agrarias (IVIA) based on sexual hybridization, embryo rescue and ploidy analysis
by flow cytometry in order to obtain new mandarin varieties with late harvest. ‘Safor’ and ‘Garbí’ mandarins
are new triploid hybrids recently released characterized by their high quality and seedless fruits. In the Citrus
Center of Citriculture and Vegetable Production (IVIA) other breeding program based on budwood irradiation
is being conducted in search of new seedless cultivars. At this moment two clones obtained from irradiated
budwood of the seedy ‘Moncada’ mandarin (‘Moncalina-6S17’ and ‘Manrad-2L09’) are in process of being
registered and exhibit excellent fruit quality. This study aimed to test the postharvest behavior of these four
new cultivars. After harvest the fruit were waxed and stored up to 30 days at 1ºC, 5ºC, or 9ºC in order to
evaluate the sensibility to chilling injury and the changes in quality parameters that occur during the cold
storage. ‘Safor’ mandarins did not show chilling injury symptoms during 30 days at any temperature studied.
In contrast, ‘Garbí’ mandarins exhibited susceptibility to chilling injury after 15 days of storage at 1ºC and 5ºC;
during this period this cultivar showed disorders related with peel dehydration that were aggravated when
the fruit were late harvested. ‘Moncalina’ and ‘Manrad’ did not show relevant symptoms related to coldinduced
damage or dehydration at 1ºC, 5ºC or 9ºC for 30 days of storage. For all mandarin cultivars assayed,
the storage at low temperature was not a limitation for the changes observed in fruit quality parameters.
358 - VALENCIA CONFERENCE CENTER, 18th-23rd NOVEMBER 2012