Pomological and oil chemical variability in walnut (Juglans regia L.) genetic resources

MARTÍNEZ, MARCELA; ALBANESE, MARÍA LAURA; NASJLETI, AGUSTÍN; LABUCKAS, DIANA; MATTEA, MIGUEL; MAESTRI, DAMIÁN

Brasil

Conferencia; CIGR - International Conference of Agricultural Engineering XXXVII Congresso Brasileiro de Engenharia Agrícola; 2008

Walnuts (Juglans regia L.) from the varieties Chandler, Franquette, Hartley, Lara, Mayette, Serr, Sorrento and Tulare were studied in order to evaluate genotypical variations in some pomological traits and oil chemical characteristics. Variability found in nut weight (NW) was between 9.35-14.9 g and in kernel weight (KW) 3.52-7.29 g, resulting in KW/NW ratios from 0.38 to 0.52. Nut and kernel size varied in a similar way indicating a good nut filling. All varieties has good colours traits with more than 90 % of their kernels fell into the “Extra light” and “Light” categories. Oil content ranged between 71.4-73.9 %. Oils obtained by pressing presented low acid, peroxide, K232, and K270 values, and moderate (247-365 mg/g oil) total tocopherol contents. Oxidative stability, as measured by the Rancimat method, was poor (2.64-3.44 hs) and it correlated positively with oleic and negatively with linolenic acid contents. Variations in unsaturated fatty acid (FA) contents were between 16.1-25.4 % (oleic acid), 52.5-58.9 % (linoleic acid), and 11.4-16.5 % (linolenic acid). According to some fruit characteristics and oil chemical composition, Serr and Tulare varieties may be evaluated as promising materials for cultivation in regions under agroecological conditions similar to those of Guanchín, at La Rioja province (Argentina).