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In order to determine the existing relationship between crop load and yield, expressed as those processed for canning (fruit weight between 100 and 250 g, canned in halves) or puree, a trial was set in a commercial orchard on Bowen, Andross and Ross cling peaches in Mendoza, Argentina. Trees grafted on Nemaguard, vase shape trained, and planted at 6 x 5 m (333 plants/ha) were used. Hand thinning was performed 20 days after the beginning of pit hardening, leaving a range of crop load between 750 and 1350 fruits per tree in Bowen and Ross and between 850 and 1400 fruits per tree in Andross. Average fruit size was determined as well as total yield or expressing it as share for industrial use (canning or puree); crop value was also evaluated. All these variables were tightly related to crop load showing similar responses for different cultivars. As crop load increases total yield increases but average fruit size decreases. Yield for canning increases as crop load increases up to a maximum of 1200 fruits/tree; after such crop load canning yield decreases. A curvilinear relationship was also found between yield for puree and total yield. Given the fruit size and yield responses to increasing crop load, fruit thinning, among other management practices, is highly determinant to maximize canning peach profitability for the growers. [ABSTRACT FROM AUTHOR]

In order to evaluate in the Region de Atacama and Region Metropolitana from Chile, the use of complementary thinners to the gibberellic acid (GA3) applied to 'Thompson Seedless' grapes. This research explored the use of naphthalene acetic acid (NAA), thidiazuron (TDZ) and benzyladenine (BA) applied to flowering plants; and Wuxal® Ca in the fruit set. During the first season, prospective assays were performed. NAA was sprayed at: 0; 2.5; 5; 7.5; 10 and 12.5 mg·L-1; BA tested concentrations were: 0, 60, 90, 120, 150 and 180 mg·L-1, and TDZ concentrations were: 0; 0.5; 1; 1.5 and 2 mg·L-1. During the second season, NAA was sprayed at 0; 2.5; 5.0 and 7.5 mg·L-1 and BA was applied at 0, 150, 300, 450 and 600 mg·L-1. On a thirth trial, 2 mg·L-1 of NAA and Wuxal® Ca applied at bloom and fruit set, respectively. NAA decreased the number of berries for cluster; phytotoxicity was detected at concentration since 7.5 mg·L-1. BA increased berry number with higher concentrations. TDZ did not show differences in thinning. Wuxal® Ca applied after NAA, decreased berry number per cluster, extending the effective period of thinning until after fruit set. [ABSTRACT FROM AUTHOR]