Impact of Organic and Mineral Fertilization in Pecan Nut on Production, Quality and Antioxidant Capacity

Abstract

The pecan nut is considered one of the most important dried fruits in the world by its classification as healthy food. The nutritional balance in the harvest is crucial for its impact on the production, quality and content of bioactive compounds. This research was carried out in the city of Aldama, Chihuahua (Mexico), where doses of mineral and organic fertilization were tested in L25 Taguchi structure with 6 factors and 5 levels by factor: nitrogen (N) 0 - 240 kg·ha-1, phosphate (P2O5) 0 - 120 kg·ha-1, potassium (K2O) 0 - 100 kg·ha-1, calcium (CaO) 0 - 400 kg·ha-1, liquid humus 0 - 3600 L·ha-1 and solid humus 0 - 8000 kg·ha-1. An average yield of 2.2 t·ha-1 was obtained; 145 nuts per kilogram, 60% of the edible part of the nut. The total phenolic content was 225.9 mg gallic acid g-1 and the antioxidant capacity was 180.9 mg Trolox g-1. It is concluded that the factor with the greatest impact on yield, quality and antioxidant capacity in pecan nut was nitrogen. It was also found that the combination of mineral and organic fertilization helps to maintain the production and quality ranges of the nut. In turn, these factors contribute to the increase in the phenolic strength and antioxidant capacity. The optimal fertilization dosis to obtain the maximum levels in production of 3.2 t·ha-1; decrease the number of nuts per kilogram to 135, increase the percentage of the edible part of the nut to 61.8%, the increase in the total phenolic content to 318.6 mg of gallic acid g-1 and in the antioxidant capacity with 187.2 mg of Trolox g-1, was 184 kg·ha-1 of N, 107.4 kg·ha-1 of P2O5, 50 kg·ha-1 of K2O y 2777 L·ha-1 of liquid humus. Finally, the mineral fertilization complemented with organic fertilization is considered a good fertilization strategy for pecan trees and its possible benefits to health and the environment.