PHYSIOLOGICAL AND GROWTH RESPONSES OF MANGO (MANGIFERA INDICA L.) TO METHANOL AND POTASSIUM NITRATE APPLICATION

The efficacy of KNO₃ (6%) and methanol (50%) when applied during the ‘off-season’ on mango flowering was compared.
Two applications of both chemicals, the first in May and the other in June, 1993, were sprayed on three-year old potted plants of ‘Julie’, a semi-dwarf cultivar, and two vigorous cultivars, ‘Graham’ and ‘Tommy Atkins’. New shoots on methanol-treated ‘Graham’ and ‘Tommy Atkins’ plants were significantly (p<0.05) longer than those in the control. ‘Julie’ flowered in June and in August and produced more panicles in response to KNO₃ than on the control plants, but methanol-treated plants produced fewer and smaller panicles, especially with the first application. ‘Graham’ and ‘Tommy Atkins’ flowered in September to October with similar panicle number and size responses to ‘Julie’ except that the first methanol application increased flower number in ‘Graham’. The first methanol application and the second KNO₃ significantly (p<0.05) lowered transpiration rate in ‘Julie’. The other cultivars tended to respond similarly with the second application of both chemicals.
Both chemicals produced higher water use efficiency (WUE) in ‘Julie’. It is suggested that the ability of KNO₃ and methanol to affect flowering is related to their relative effect on WUE.

V International Mango Symposium

V. Shongwe, Laura B. Roberts-Nkrumah

shoot growth, flowering, transpiration rate, carbon assimilation, water use efficiency

https://doi.org/10.17660/ActaHortic.1997.455.9