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This study aimed to assess the impact of ethrel spraying on cassava leaf abscission at different stages of cultivar development. Two experiments were performed using randomized block designs, with 15 total treatments (three repetitions of five conditions) arranged according to the factorial scheme 3 x 5. Experiment 1 (ethrel application in the vegetative development period) consisted of three seasons (November 2013 and 2014, January and February 2014) and four concentrations of ethrel (1,500, 3,000, 4,500, and 6,000 ppm) and a control (no application); Experiment 2 (application in pre-harvest period) consisted of three periods of ethrel spraying (20, 40, and 60 days before harvest), four ethrel concentrations (1,500, 3,000, 4,500, and 6,000 ppm) and a control (without ethrel). The characteristics evaluated included the number of fallen leaves at 20 and 70 days after application, total leaf dry mass and foliar degreening. The effects of different concentrations and times of application of ethrel were significant during the first seven days. Ethrel application during the second period of vegetative development did not affect the number of fallen leaves over a period of 70 days.

The objective of this study was to evaluate whether the inhibition of gibberellin biosynthesis affects the morphophysiological traits of potted ornamental Capsicum baccatum and Capsicum annuum growing under shade house conditions. Plants maintained in 2.7 L pots were arranged in a completely randomized design in a 2x4 factorial consisting of two pepper cultivars Chapéu-de-frade (C. baccatum) and Vulcão (C. annuum) and four paclobutrazol (PBZ) concentrations (0, 25, 50, and 75 mg L-1) with four replicates. At 30, 45, and 60 days after treatment, the plants were analyzed, and data were submitted to the analysis of general and regression variance. Gibberellin biosynthesis inhibition affected the morphophysiological and biochemical evaluations. For most evaluated traits, no interaction between factors was observed, suggesting that both pepper cultivars had a similar response to the growth regulator. PBZ-induced inhibition of gibberellin biosynthesis improved plant water status, which enhanced the vigor of potted pepper plants. The dramatic reduction of upper leaves promoted by plant growth regulators compared to basal ones negatively impacted the visual ornamental aspect of Chapéu-de-frade peppers.