LIBRO-CONGRESO-CITRUS

S17
growing areas are from Coquimbo Region (29°SL) to O’Higgins Region (34.45° SL) where the dry summer
and Mediterranean climate prevails. Presently 18,934 ha are planted in total, distributed in oranges (41.4%),
lemons (37.5%), mandarins and clementines (19.1%), grapefruits (1.52%), limes (0.3%) and tangelos (0.2%).
Regarding exports, a total 134.7 million dollars were exported, which included oranges (39.6%), lemons
(27.2%), clementines (22%), mandarins (10.5%), and grapefruits (0.7%). Rootstocks have a strong influence
on the variety grafted on citrus. The most used ones in the last four years are: ‘C-35’ (oranges, mandarins,
grapefruit and lime), Citrus macrophylla (lemons and limes), ‘Rubidoux’ (oranges and grapefruits) and
‘Carrizo’ (oranges, mandarins, grapefruit and limes). With regard to varieties, the most used in lemons are:
‘Fino 49’, ‘Eureka’, and ‘Messina’; in oranges, ‘Fukumoto’, ‘Parent Washington’ and ‘Lane Late’; in mandarins,
‘W. Murcott’, ‘Orogrande’ and ‘Clemenules’; and in grapefruit, ‘Star Ruby’. Over the last years, the Chilean
industry has been interested in introducing protected varieties into the varieties offered.
S17P22
Influence of gamma irradiation on seedless citrus production: pollen germination and fruit quality
Bermejo A., Pardo J., and Zaragoza S.
Instituto Valenciano de Investigaciones Agrarias (IVIA), Centro de Citricultura y Producción Vegetal, España. bermejo_alm@gva.es
Gamma irradiation is widely used to obtain seedless citrus fruits. Herein, different new clones obtained
by bud irradiation of several seedy citrus cultivars grown in the Mediterranean climate were studied to
assess seedlessness, pollen germination, fruit characteristics and quality attributes. Findings indicate that
irradiation altered aspects other than seedlessness, such as pollen germination, and some of the clones
presented different size, acidity and maturity index. Fruit quality and nutritional bio-components also were
affected. Our results indicated high contents in natural antioxidants as vitamin C, carotenoids and phenolic
compounds in these citrus varieties, and provide a qualitative and quantitative survey of the fruit taste and
organoleptic quality. High-performance liquid chromatographic methods were used to identify and quantify
of these bioactive compounds. These aspects are necessary for the consumer that demands the prevention
of health problems through nutrition and certain fruit quality traits including fruit size, internal quality, good
rind colour and easy peeling. All irradiated clones examined presented lower seed numbers and reduced
pollen germination compared to the corresponding controls, and some of these clones, which ripen late in
the season and whose fruit quality is maintained or improved, are in the process of registration. In conclusion,
budwood irradiation is a suitable technique to improve cultivars, produce seedless cultivars, adjust ripening
time or raise the content of health-promoting compounds.
S17P23
Identification of new volatile compounds in a citrus hybrid mandarinquat ‘Indio’ (Citrus japonica
× Citrus reticulata)
Delort E., Decorzant E., Casilli A., and Jaquier A.
Firmenich SA, Analytical Innovation, Switzerland. estelle.delort@firmenich.com
The volatile composition of mandarinquat peel extract was investigated for the first time. At first sight,
GC/MS chromatograms appeared to be very complex, due to the probable addition of the traits of both
parents. Consequently, many peaks could not be identified due to co-elutions. Further investigation based
on more sophisticated processing procedure (deconvolution software) and advanced chromatographic
techniques (two-dimension GC/MS) have been carried out. Compared to deconvolution software, the use
of a two-dimension GC/MS allowed elucidating most of the co-elutions. Finally, our study showed that,
even if the hybrid contained many of the compounds found in one or both parents, some compounds were
lower-expressed; some others were even absent in the hybrid. Surprisingly, a few compounds, which have
never been identified in any of the parents, were identified. The identification of new volatile compounds in
hybrids may result from the interaction between the two genomes during hybridization, which may cause the
activation of some genes by the other genome which are otherwise silent in the parent genome.
316 - VALENCIA CONFERENCE CENTER, 18th-23rd NOVEMBER 2012