Pinecone failure, hydrogel, fertilizer and volume of containers in the production of araucaria seedlings

Abstract

The objective of this work was the evaluation of initial growth and quality of araucaria seedlings under the influence of alterations to different proprieties of the substrate. Four different experiments were installed, comparing volume of tubes, concentrations of controlled release fertilizer (FLC), proportion of crushed pinecone failures (substrate characteristics were also evaluated) and the effect of hydrogel concentrations in seedlings derived from different mother trees. The evaluations were carried out 10 months after sowing, varying according to the experiment, and were comprised of height, diameter, height/diameter ratio (h/d), survival rate and germination speed index. The seedlings developed inside the larger tubes (280 cm3) averaged higher in height, diameter and h/d ratio. The 6 g L-1 dose of fertilizer generated higher averages for all analyzed variables. The addition of pinecone failure to the substrate improved some physical attributes such as density, total porosity and aeration space, however it worsened the attributes related to water availability in the substrate. As for the growth of seedlings, the addition of pinecone failure did not change the height, diameter and h/d ratio. The use of hydrogel (3 g L-1 and 6 g L-1) generated better results for height. It is recommended the use of 180 cm³ tubes and 6 g L-1 of the contloed release fertilizer. Pinecone can be used in the substrate, as well as hydrogel as a additional resource.