RESPONSE OF LITCHI (Litchi chinensis Sonn.) TO NPK FERTILIZATION IN NORTHERN OAXACA, MÉXICO

Abstract

Responses of six years old litchi (Litchi chinensis Sonn.) trees cv. ‘Brewster’ to NPK fertilization at north of Oaxaca state were evaluated from 2009 to 2011. Six dosage treatments (0, 25, 50 75, 100 and 125 %) of the 50-130-50 kg ha^-1 of N, P₂O₅ and K₂O were used. Additional treatments were: 100 % dosage + 3.6 t ha^-1 of compost, 100 % + 18 kg ha^-1 of micronutrients, and 100 % + 18 kg ha^-1 of micronutrients + 720 kg ha^-1 of Ca(OH)₂. The first fertilization was applied on November 2009, but no response was obtained in 2010. In 2010 and 2011 the fertilization was divided in two parts. The first half was applied in August 30, 2010, and the other in February 11, 2011. The results reported here correspond to the 2010 - 2011 period. Highest concentrations of N, P and K in the leaves at the flower bud stage were obtained with the highest dosages. The highest amounts of flowers and fruit yield compared to the control were observed with 100 % of NPK + micronutrients. Highest chlorophyll contents were found with the 125 % dosage. The highest values of new shoots dry weight and leaf area were obtained with the 100 % dosage + compost. Positive correlations between foliar nitrogen with new shoots weight and leaf area (r = 0.72 and r = 0.65, respectively), were found. It is concluded that litchi trees fertilized with NPK , compost and micronutrients increased N, P and K concentration in the leaves, amount of flowers, fruit yield, green color of leaves, new shoots weight and leaf area. No response to calcium hydroxide application was observed in litchi trees.