Stenopermocarpy in ‘Ataulfo’ mango

The main problem that affects the 'Ataulfo' mango in Nayarit, Mexico, is the high production of stenospermocarpic fruits that reduces yield and productivity. In Mexico, the causes of the problem were not known, neither technology to reduce it. The objective was to determine the causes and generate technologies to decrease the production of seedless fruits and increase the yield. During 2018 and 2019, different research and validation activities were carried out in Nayarit, Mexico, in commercial ‘Ataulfo’ mango orchards with a high incidence of stenospermocarpic fruits. The first activity consisted of a study on the effect of temperature on the development of the inflorescence, the embryo, and the formation of seedless fruits. The second was to validate the technology with the use of growth regulators to increase the production of fruits with seed and fruit size and their relationship with the number and size of cells. Depending on the temperature, there are two flowering flows, the second flow from anthesis to the fruit set coincided with extreme temperatures; minimum of 15°C average and maximum above 35°C. In fruits of the second flow, abortive embryos were observed from the first stages of development and the highest production of stenospermocarpic fruits (75%) occurred in this flowering flow. The increase in the size of these fruits was associated with greater cell division and elongation. Cytokinins assumed an important role in cell division while gibberellins had it in cell expansion. The effect of regulators was corroborated to increase the size of the stenospermocarpic fruit (>100%) and increase the production of fruits with seeds.