Production and quality of eucalyptus mini-cuttings using kaolin-based particle films

摘要

Considering the expansion of forest plantations over the Brazilian territory and the imminent increase in air temperatures due to global warming,the search for technologies that ensure high levels of productivity and high quality plants in clonal nurseries is essential.Applying kaolin-based particle films(KBPF)has been used as a physical barrier to reduce the negative effects of excessive solar radiation and adverse temperatures.The effects of KBPF on production and physiological quality of eucalyptus mini-cuttings were evaluated during two different seasons.A randomized block design was used,consisting of five treatments and four replications.Five concentrations(0,3%,5%,7%,and 10%)were tested here and six weekly replicates of each concentration was applied.The different kaolin concentrations and seasonal variations resulted in a quadratic response of the leaf SPAD reading during both daily evaluation periods.KBPF applications resulted in a quadratic response of photochemical efficiency in the morning period,and an increasing specific leaf weight linear response,and during the dry season,the different kaolin concentrations resulted in a bud length quadratic response.The results indicated that the kaolin application maintained the production and yield index statistically equal between weekly KBPF applications,improving photochemical efficiency,leaf thickness,SPAD reading,and bud length.The use of KBPF could reduce the intervals between collections of mini-cuttings and increase nursery yields in environments that present high temperatures.