Yield, quality, alternate bearing and long-term yield index in pecan, as a response to mineral and organic nutrition

The pecan nut is produced in 57 countries in the world. Alternate bearing is one of the main biological problems that affect pecan cultivation. Mineral and organic fertilization is a good strategy to maintain and increase pecan nut production. In this study, several mineral and organic doses of fertilization were tested using a factorial arrangement 56 bounded to 25 treatments was used in structure Taguchi L25: 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. The study was carried out in Aldama city, Chihuahua (Mexico). An average yield of 2.4 t ha-1 was obtained, 157 nuts per kilogram and 58.9% of edible nut. The average alternate bearing intensity was 31.58%, and the long-term yield index (IRLP) was 9.59%. It is concluded that the factors whit the greatest impact on the analyzed variables were N and P2O5. In addition, it was found these mineral and organic fertilization systems help to reduce alternate bearing in pecan and simultaneously improve production and long-term productivity index. Optimal fertilization doses were defined: 181.4 kg ha-1 of N, 93.5 kg ha-1 of P2O5 and 3287.2 L ha-1 of liquid humus. Finally, the mineral fertilization complemented with organic fertilization is considered a good fertilization strategy for pecan trees, to increase production and with lower environmental impact.