Nutrient deficiencies in three pine species (Pinus sp.) grown in hydroponic culture for one growing season

Abstract

The effects of nutrient deficiencies on three pine species (Pinus pinaster Ait., Pinus pinea L. y Pinus halepensis Mill.) are studied in this work. Seeds were planted in a mixture of peat and perlita. When the seedlings reached an adequate size, they were transplanted to hydroponic culture and grown for 4 months (April - July, 1998). Nutrient solutions lacking N, P, K, and Fe, and a control solution were used. During this period, morphological attributes (height, diameter, needles length, and dry weight of shoot and root) and physiological attributes (chlorophyll and nutrient content of needles) were measured, as well as visual symptoms produced by the nutrient deficiencies. Differences were observed depending on the lacking nutrient and the pine species. Nutrient deficiencies affected morphological and physiological attributes and caused growth decrease and visual symptoms. Nevertheless, these effects reached different importance depending on the lacking nutrient and pine species. For example, Fe deficiency caused the greatest and quickest effects, whereas K deficiency hardly affected. Deficiencies effects were greater in shoot growth than in root growth. P. pinaster was the most affected pine species.