Résumé
Brazil is leader of concentrated and frozen orange juice production in the world. However, the extension of fresh orange and mandarin market could provide higher gains for the producers, as occurred in Spain and California (USA). Part of Spanish and Californian success is due to a marketing strategy centered on high quality fruits with aggregated value (bright orange color, easy-peeler fruits, balanced sugar/acidity, etc.). However, one of the difficulties in relation to mandarin quality is that it highly depends on genotype and cultivation area (climate and environment conditions): in tropical regions, the mandarin color and acidity are less intense, which could affect the consumer acceptance. To improve the understanding of fruit quality elaboration on tropical regions, our strategy first consist on phenotypic and molecular comparative studies of the same citrus varieties cultivated in Tropical (Bahia state, Brazil) and Mediterranean (Corsica, France) climates. We selected 45 citrus genotypes (36 mandarins and hybrids, 8 oranges and 1 grapefruit) presented in Embrapa (Bahia State, Brazil) and INRACIRAD (Corsica, France) germplasms, and we verified their genetic conformity by molecular analysis using 12 SSR markers. All oranges, the grapefruit and 14 mandarin varieties presented the same genetic background in both germplasms and have been selected for further biochemical, molecular and OMICs analysis. In parallel, in order to determine with precision the maturation phase for fruit harvesting (3 maturation stages), maturation curves (phenotypic analysis, total soluble solids and acidity) were obtained on the all or part of the 45 genotypes during 2012 and 2013 at Embrapa. Mature fruits were mainly obtained between November and February. The obtained data were also related with the climate records from the Experimental Station of Embrapa (temperature, atmospheric pressure, relative humidity, rain precipitations). These results are promising and important as prerequisite for subsequent deeper biochemical and molecular analysis of fruit quality determinism and genotype/environment interaction studies. Work supported by: CAPES, Agropolis, CNPq, FAPESB, Cirad, Embrapa. (Texte intégral)