Different rootstocks can change the photosynthetic performance of the 'Uba' mango scion after recurrent drought events

Key messagePI(TOTAL), PIABS, DI0/RC, and & delta;R-0 are good markers of water stress in mango trees, demonstrating that consecutive drought cycles can develop differential acclimatization, depending on the rootstock used.Drought stress is one of the premier limitations to global agricultural production due to the complexity of the water-limiting environment and changing climate. In addition to indicating plant drought stress, photosynthetic performance is also determined by the scion/rootstock combination. The chlorophyll a fluorescence analysis is a reliable method to identify the most promising rootstock in the production of 'Uba' mango seedlings. We tested the hypothesis that different rootstocks can change the physiological responses related to chlorophyll a fluorescence, gas exchange, and proline content of different combinations of mango scion/rootstocks after three consecutive drought cycles, identifying the most vigorous rootstock with the ability to generate 'Uba' mango trees with greater differential resistance to drought. The Oleo rootstock (UC2/Oleo combination) has the greatest ability to imprint differential drought resistance in 'Uba' mango scions, generating plants with more vigor and better resistance to water deficit. The results suggest that the plant's consecutive cycles of drought have been "learned" as a resistance mechanism to cope with severe water shortages in the future.