CRECIMIENTO DE PLÁNTULAS DE Pinus greugii Engelm. EN RESPUESTA A LA FERTILIZACION

Abstract

The "San Cristóbal" design was used in seedlings of Pinus greggii growing in nursery conditions, to analyze the direct effects and the interadion effects of nitrogen (N), phosphorus (P) and potassium (K) in their growth and development in this cc-ndition. The data obtained from the development of seedlings were used in !;,rowth functions and represented in surface responses. In addition, the height, d,ameter, and shoot, root and total biomass were used to construct morphological indexes which are helpful to estímate seedling quality. Results showed that nutrients effects are less important than the interactions between them, and the dynamic nutrient relationship significantly affects seedling morphology, especially biomass acumulation and distribution. The values obtained for the quality indexes (Dickson and thining) were peor, mainly because of an excessive shoot growth over root growth due to an excess in one nutrient or another, specially the high concentration of nitrogen, which promete the shoot growth. lt was evident than nutrient balance is a key issue on nursery seedling development, thus, it is advisable to conduct experiments assessing single­nufrient doses and regimes in search for both physiological and operational optimum for P. greggii.