Figure 5.

Effect of girdling on the photosynthetic activity response to partial defoliation. Photosynthetic rate per internal CO₂ concentration (Ci) of source leaves in nondefoliated plants (hatched bars) and the remaining tomato leaves after partial defoliation of the other leaves (empty bars). Defoliation was performed on mature variety M82 plants at the reproductive stage. Lower stem girdling was performed immediately after partial defoliation. Plants were grown in a temperature-controlled greenhouse (25°C/18°C day/night). Data represent means (±SE) of five biological replicates. Asterisks indicate significant differences between partially defoliated and nondefoliated plants at p < 0.05 by Student’s t-test.