The 2010 ASHS Annual Conference

Two field trials were conducted to determine the effect of pruning on the incidence of bacterial spot (Xanthomonas perforans) and on growth and marketable yields of tomato (Solanum lycopersicum). Seedlings of ‘Tygress’ and ‘Security 28’ tomato were planted in fumigated beds and submitted to no pruning, light pruning (2 stems left) and heavy pruning (1 stem left) at 3 weeks after transplanting. Plots were left either to natural bacterial spot infestation or inoculated with 1 x 10⁶ cfu/mL. The results indicated that the three factors (cultivar, bacterial spot inoculation, and pruning) were not significant for plant height at 6 weeks. There was significant effect of each of the individual factors on total marketable fruit weight, but none of the interactions were significant. ‘Security 28’ and non-inoculated plants had higher total marketable fruit weight than plots planted with ‘Tygress’ and inoculated plants, respectively. There was no difference between plots with lightly-pruned plants and non-pruned plots, whereas heavy pruning reduced yields by 11% in comparison with no pruning.