In Nicaragua. Potassium nitrate foliar spray induces bloom in mango orchard.
Maas E. F.
Author Affiliation: Canadian Executive Service Organization, Toronto, Canada.
Better Crops International 5 : 4-5
Abstract : A very low flowering percentage is reported for mature trees of several cultivars in a 350-ha orchard in lowland Nicaragua, where the range of minimum night temperature was 20-23°C and winter chilling did not occur. Bark ringing, although effective in inducing flowering, proved too injurious for repeated use and other cultural practices inducing tree stress were not effective. In Mar. 1988, experiments began on trees of the cultivars Keitt and Tommy Atkins, grown with or without irrigation, comparing the following treatments: ringing; a 2% KNO3 foliar spray [in Nov.]; P and K fertilizer each at 2 rates [unspecified]; application of molasses beneath the trees to reduce any excess of soil N; and untreated control. The KNO3 spray, which was applied on 15 Nov. at the end of the rainy season, resulted in 100% flowering 2 weeks later; at the same time all ringed trees came into flower. The other treatments failed to induce flowering. The response to the foliar spray was equally good on unirrigated and irrigated plots, attributable to a prolonged rainy season which may have ensured good bud maturity.