Introduction:

Nitrogen is the nutrient most demanded by pecan trees, therefore, is a limiting factor for development, production and quality of the nut. However, given the increase in fertilizer prices and the effect of overuse of environmental pollution, now becomes more evident the need for nutrients sustainable manner. An alternative to reduce application of inorganic nitrogen fertilizers in pecan is complemented with the application of compost, vermicompost, worm leachate microorganisms and enhancing soil fertility such as mycorrhizae. So the aim of this study was to reduce the use of inorganic nitrogen to the soil by adding organic amendments and enhancers microorganisms’ soil fertility without affecting production and quality.

Method:

The study was conducted in Aldama Chihuahua, during the 2010-2012 cycles on trees 'Western Schley', used a Taguchi L16 structure to four factors and four levels for each factor: Nitrogen 330, 220, 110 and 0 kg ha-1; compost 0, 2.5, 5.0, 7.5 t ha-1; earthworm humus (OptiHumusMR) 0, 1.5, 3.0, 4.5 t ha-1 and mycorrhizae (Sehumic-VamMR) 0, 7.5, 15.0, 22.5 g cm-1 trunk. The content of organic matter and nitrates in the soil, production and nut quality was determined, which were analyzed by response surface.

Results:

Although it was possible to reduce nitrogen application for a production of 2.9 t ha-1 level did not allow a good quality pecan nut and achieve an adequate content of organic matter and nitrates in the soil. For a yield of 2.9 t ha-1 with 153 nuts kg and 59.4% of edible nut, 1.06% organic matter and 183 ppm of nitrates in ground requi-laughed 305 kg of N, 6600 kg of compost, 3500 kg vermicompost and 18 g mycorrhizal by g cm-1 of trunk; this dose could ensure the quality of current production and provide nutrients to the tree for the next production.

Discussion or Conclusion:

It was possible to reduce the application of nitrogen as 27 kg ha-1 for a production of 2.9 t ha-1, so that nitrogen alone can not increase soil fertility and improve the quality of the nut, which is required the addition of organic amendments and mycorrhizae. With these preliminary data, we can conclude that the inorganic nitrogen fertilizer and mycorrhizal supplemented with organic amendments, could be a viable option for improving soil fertility and pecan production alternative.

        · resumen en Español     · texto en Español     · Español ( pdf )