LEAF NUTRIENT SUFFICIENCY RANGE FOR GUAVA (Psidium guajava L.), IN THE EASTERN REGION OF MICHOACAN, MEXICO

Abstract

Guava (Psidium guajava L.) is an important crop in the Eastern region of Michoacán, Mexico, where it covers 9260 ha, and one of the problems presented is poor nutrition. In relation to the nutritional status of guava, the nutrient sufficiency range was determined, as well as the effect of soil and orchard management factors affecting nutrient nutrient status of trees in the Eastern region of Michoacán, México. Soil samples were taken for physical and chemical characterization, and leaf samples at 25 to 50 % flowering stage to determine nutrient concentrations 31 orchards in 2006, 37 in 2008 and 39 in 2011. In addition, information on orchard management and fruit yield was collected. Regression models were adjusted to estimate yield as a function of nutrient foliar concentration, and for these concentrations as a function of nutrient amounts applied as fertilizer, nutrient content and soil chemical properties, and orchard management factors. The nutrient concentrations in the leaf were related to: 1) the respective fertilization for N, P, K, Ca, Mn and Cu; 2) nutrient content of the soil for all nutrients, except for B, and 3) some soil and orchard management factors that increased or decreased the nutrient uptake by the plant. The adequate foliar nutrient sufficiency range was associated with moderately high and high soil nutrient contents, and fertilizer amounts recommended to be applied in orchards for N, P, K, Ca, Mn and Cu.