A comparison of the fruit parameters of 12 Opuntia clones grown in Argentina and the United States.

Fruit parameters were measured on the same 11 clones grown at 27degreesN latitude in Kingsville, TX, U.S.A. with 690 mm annual rainfall and at 27degreesS latitude in Santiago del Estero, Argentina with 605 mm annual rainfall. The major difference between the climates was that the rainfall in the last 2 months prior to fruit maturation was 110 and 290 mm in Argentina vs. 86 and 13 mm in the U.S.A. The absolute fruit sugar concentrations and the ranking of the varieties for fruit sugar was virtually the same in both climates, indicating considerable stability for fruit sugar. In contrast, in many cases, the fruit fresh weight and the percentage of pulp was significantly greater in Argentina with higher rainfall at the end of the fruit maturation period. The ranking of the varieties for seeds per whole fruit was similar but in Argentina, a few clones had significantly less seeds per fruit than in the U.S.A. Due to both a larger fruit size and a greater percentage of pulp to whole fruit for several clones grown in Argentina, the ranking for percentage of seeds per edible pulp portion was different in the U.S.A. and Argentina. While the Italian fruit variety Gialla had very similar fruit sugar and fruit weight in Italy and Argentina, the consumer perception of Gialla was that it was not a 'juicy variety'. Our measurements indicated that it had identical juice to the other varieties, but lacked fruit firmness in Argentina. For the first time, we report juice yields ranging from 53.6 to 69.8 ml 100 g(-1) of pulp with a mean density of 0.95 g cm(-3). (C) 2002 Published by Elsevier Science Ltd.