Effect of mineral element concentrations on lenticel damage of mango (Mangifera indica L.) fruit in Mpumalanga Province, South Africa.
Kaiser C., Westgate P. E. C., Helm G.
Author Affiliation: Department of Plant Production & Soil Science, University of Pretoria, Pretoria 0002, South Africa.
Research Journal - South African Mango Growers' Association 24 : 47-49
Abstract : 'Tommy Atkins' mango fruits were harvested when physiologically mature from 30 different orchards from Bavaria Estates, Mpumalanga Province, South Africa. Fruits were passed over a packing line as per export standards and held for 28 days in regular atmospheric storage at 10°C and 95% RH. Thereafter, fruits were evaluated for the presence or absence of lenticel discoloration. Exocarps were removed from all fruit and analysed for macro- and micronutrients. On average, there were no significant differences in macro- or micronutrient concentrations in the soils or fruits, either with or without lenticel discoloration. However, nitrogen (0.95% dry mass basis) and calcium (0.83% dry mass basis) concentrations were lower and potassium concentrations were higher (1.15% dry mass basis) in fruit exocarps with lentil discoloration when compared to those of fruit exocarps without lenticel discoloration, i.e. nitrogen (1.06%), calcium (1.35%) and potassium (1.03%). Similarly, micronutrient concentrations of fruit exocarps without lenticel discoloration were higher than those exocarps of fruit with lenticel discoloration, i.e. zinc (21 vs 15 mg kg-1), copper (152 vs 90 mg kg-1), manganese (190 vs 128 mg kg-1), iron (69 vs 52 mg kg-1) and boron (48 vs 31 mg kg-1). Although results were not significant, growers would be well advised to consider keeping macronutrients (nitrogen and calcium) and micronutrients (zinc, copper, manganese, iron and boron) in the sufficiency range as far as leaf and soil recommendations are concerned.