Doses of controlled release fertilizers in the chlorophyll content and production of seedlings of grapia

Abstract

The objective of this work was to define the best doses of Osmocote® for Apuleia leiocarpa seedling production for 60 and 90 days residence in the seedling nursery after the transplanting and to observe the chlorophyll index response of the seedlings
during the studying period. The experimental design used was completely randomized, with five treatments and ten repetitions. The treatments consisted of increasing doses of Osmocote® ( 0, 3, 6, 9 e 12 kg m-3 of substratum). There chlorophyll index, seedling
diameter and height at 60 and 90 days after transplantation, leaf area, aerial part dry mass, root length and dry mass at 90 days after transplantation. Considering the average values of the points of maximum technical efficiency, seedling diameter and height, it was concluded that the best dosage of Osmocote® for A. leiocarpa seedling production, in a period of 60 and 90 days after transplantation are 7.97 and 7.73 kg of Osmocote® m-3 of substratum, respectively. The chlorophyll index demonstrated quadratic behavior for Osmocote® doses and positive correlation with the variables height and seedling diameter.