Speakers - PMBWC2025

Biography

Dr. AMLAL Fouad is an accomplished agronomist and expert in plant nutrition. With a doctorate in the field, he has dedicated his career to advancing agricultural science through research and innovation. Dr. Amlal has authored over 15 scientific articles, contributing valuable insights into topics such as fertilization, irrigation, and the impact of climate change on agriculture. His work focuses on developing sustainable practices to improve crop productivity while addressing environmental challenges. A respected figure in his field, Dr. Amlal combines academic expertise with practical solutions to drive progress in agricultural sustainability and resilience.

Abstract

This study aims to track the dynamic of macronutrients in leaves and fruits of peach varieties to enhance fertilization strategies and improve yield and fruit quality. Two varieties of peach were studied: Garbaja as an early variety, and Corindon as a late variety, grown under drip irrigation on calcareous soil. For each variety, leaf samples were collected monthly, and fruits sampling was started 30 days after full bloom (DAFB), at an interval of 15 days with 4 replications (n=4). The nutritional status of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) was determined.
Leaf macronutrients’ contents showed variation over time. Leaf N and P contents showed early-season peaks (at 30 DAFB), with N reaching 3.1% and 4.7% for Garbaja and Corindon respectively, while P was 0.4% in both varieties. This result reveals the high demand for these macronutrients in the early stages of peach tree growth. These levels declined progressively until 180 DAFB, then stabilized at a N content of 2.2% for both cultivars and leaf P levels of 0.12% and 0.16% for Garbaja, and Corindon, respectively. The leaf potassium (K) content of both varieties reveals a marked decrease at harvest time (1.65 % for Garbaja, 1.4% for Corindon) due to its translocation to fruits. These levels reached the peak in June with 2.1% and 2.3% respectively for early and late cultivars. Furthermore, leaf Ca and Mg content of Garbaja showed the same pattern, peaking at harvest (4.8% and 1.13% respectively); then, fluctuated between 3-4.2% and 0.8-1% until leaf fall stage, indicating a gradual stabilization. However, for Corindon, leaf Ca content increases continuously from 1% at set fruit to 5.7% at leaf fall stage. While the Mg level increased progressively to peak at 1% in post-harvest, then stabilized at 0.82% until the end of the season.
On the other hand, fruit nutrient uptake showed continuous translocation, reaching a total uptake of 44 kg/ha N, 14 kg/ha P, 64 kg/ha K, 4.9 kg/ha Ca and 5.7 kg/ha Mg for early variety, compared to 56 kg/ha N, 15 kg/ha P, 86 kg/ha K, 4.4 kg/ha Ca and 4.9 kg/ha Mg for the late cultivar. This result suggests higher macronutrient use efficiency in late-maturing varieties, due to extended fruit growth stage, maximizing uptake and fruit yield.
Regarding the daily removal kinetics, early variety reveals uninterrupted increasing translocation of macronutrients through the fruit stage growth. The highest rate recorded 10 days before harvest, reaching 1.2 (N), 0.46 (P), 2.3 (K), and 0.21 (Mg) kg ha-1 day-1. For Ca, this high rate was recorded at fruit cell growth stage, reaching 0.12 kg ha-1 day-1. However, Corindon exhibits a significant halt of macronutrients translocation at stone hardening stage. The fruit uptake rate peaks at 1, 0.4, 1.8, 0.11, and 0.15 kg ha-1 day-1 for N, P, K, Ca and Mg respectively, 30-45 days before harvest.
These results underscore the necessity of early varieties to benefit from continuous fertilization throughout their short growth cycle. Whereas late varieties require sustained nutrient availability during their extended growth phases with a significant reduction in stone hardening stage period. Thus, this study provides practical guidelines for precision fertilization and nutrient management, laying a foundation for sustainable orchard practices.