Flower induction in MD-2 pineapple using growth regulators and leaf pruning to obtain off-season fruit

Resumen

Objective: To prevent natural flowering of pineapple using concentrations of CPA and pruning levels, as well as to determine the flowering efficiency of MD-2 pineapple covered with shade netting, with the application of ethylene, in order to obtain off-season fruit.

Design/methodology/approach: The experiment to prevent flowering was a randomized block design with four replications, in split plots; a: 0, 75, and 128 mg L⁻¹ of 2,3-chlorophenoxypropionic acid (CPA) and; b: 0, 30, and 50% pruning; treatments were applied on November 6, 2022. Flowering percentage was measured in February and April 2022. The experiment on floral induction consisted of: a) plants covered with shade netting and b) plants in open air; 18 samplings were performed with 20 plants; inflorescences were counted and analyzed using Student’s t-test (α = 0.05); the per-hectare dose was applied three times with 2 kg of ethylene with 20 kg of activated charcoal. Results: Pruning decreased natural flowering, and the response improved when combined with 75 mg L⁻¹ of CPA. At 128 mg L⁻¹ of CPA, excellent results were obtained, but the dose can be reduced to achieve the same effect when combined with pruning. The treatment without shade netting had 94% floral induction efficiency, while the one covered with shade netting had 49%. Study limitations/implications: These results can be applied in Veracruz and Oaxaca, Mexico, in plantations with plastic mulch. Findings/conclusions: Pruning prevented flowering, and its effect was enhanced with the lower concentration of CPA; additionally, shade netting reduced flowering when ethylene was applied during periods of high temperatures.