Macronutrient and micronutrient foliar sprays vs. water stage fruit split in pecan Carya illinoinensis

Abstract

Northern Mexican pecan growers from Coahuila reported yield losses caused by the water stage fruit split (WS) probably linked to nutrient deficiencies. Therefore, the effect of foliar fertilizations on the occurrence of WS in Wichita and Western pecan cvs. was evaluated. First, trees were sprayed with macronutrients, micronutrients or both. At the midpoint of the growing season, the percentage of split nuts was measured and the leaflets from leaves next to nut clusters containing non-split and split fruits were sampled to measure their nutrient concentration. The WS was only detected in Wichita trees, but even if the fertilizations improved their nutrient status, compared to non-fertilized control, they did not significantly impact the WS occurrence. However, leaflets next to split fruit containing clusters showed higher nitrogen (N) and lower iron (Fe) concentration than leaflets next to non-split clusters. This suggests that N and Fe play an important role on the WS disorder.