Best Management Practice of Nutrient of Olive Orchards in Rainfed and Irrigated Areas of Morocco


25 Mar 2014

2013 Annual Interpretive Summary

This study was conducted under rainfed and irrigated farming conditions in the Tensift-Al Haouz region in collaboration with INRA Marrakech. Two on-farm experimental sites were selected with olive orchards in irrigated and rainfed areas of Marrakech and Essaouira provinces, respectively. At each site, four treatments were used, viz., plot without additional fertilization, farmer practice (FP), fertilization based on nutrient removal, and fertilization based on foliar analysis. To determine the initial status of soil fertility, soil samples were taken from the experimental plots and analyzed for pH, CEC, N, P, K, and soil organic matter. Tree leaves were sampled between the end of June and mid-July from olive groves of the on-farm experiments and also from 19 and 15 olive groves sites in Marrakech and Essaouira region, respectively.

Foliar analysis showed a high spatial variability of nutritional status of macro- and micro-nutrients of olive groves in both regions. On average, 67% of the sampled sites were deficient in N, while all sites were deficient in P. Potassium was deficient at all sites in the rainfed area and in 90% of the sampled sites in irrigated area. Magnesium was more available (in the range of the optimum level) in 58% of sampled sites in the rainfed area compared to 15% in the irrigated area. Among the foliar micronutrients, Cu was not deficient in any of the sites and in both areas. Iron was at optimum level in 95% of the sites, while Mn was deficient in 40% of the sites. Deficiency of Zn was more prominent (52% of sites) in the rainfed area than in the irrigated area (31% of sites). According to the results of the foliar composition, additional fertilizers will be applied in the two on-farm experimental plots in February and March 2014 at rainfed and irrigated sites, respectively. Fertilizer recommendations will also be provided to the local farmers where olive orchards leaves were sampled and analyzed.