|Authors: ||M. Radi, M. Mahrouz, A. Jaouad, A. Gaouji, M. Tacchini, S. Aubert, M.J. Amiot|
The effects of different levels of NPK fertilizers on the biochemical and technological characteristics of apricot were studied.
Apricot fruits (var.
Canino) were picked in the Marrakech area (Morocco). An experimental design with four factors: N,P,K, each one at two levels and two modes of N feeding (either 1/3 in February and 2/3 in April or 2/3 in February and 1/3 in April) was used.
The weight of the fruits, refractometric index, dry matter, sugar and organic acid content, and free acidity were measured in apricots at the commercial maturity stage.
The main phenolic compounds were identifield and their concentration determined using HPLC. Apricot fruits from trees fertilized with 80 kg nitrogen/ha showed a significantly higher content in phenolic compounds, a slightly higher sugar concentration and a lower organic acid concentration than those fertilized with 150 kg nitrogen/ha.
In this latter case, the weight of the fruits was higher.
In contrast, fertilizations with the lowest P and K levels (respectively 30kg/ha and 60kg/ha) resulted in lower concentrations in phenolic compounds, sugar content, and dry matter, but higher free acidity and fruit weight, when compared to the fruits having received the highest P and K levels (respectively 90kg/ha and 120kg/ha). The mode of N feeding seemed to play a major role in the quality of apricot fruits.
In addition, our results showed great interactions between N, P and K fertilization.