Initial assessment and nutritional status of hybrid eucalyptus sp. in the municipality of Colorado Do Oeste, Rondnia State - Brazil

The objective of this research was to determine the initial growth, nutrition and soil fertility of Eucalyptus plantation in Rondonia State, Brazil. The treatments consisted of four hybrids (VM1, H13, GG100 and I144) and four replications, each plot contained 30 plants, totaling 480 plants. The VM1 clone was obtained from the hybrid of Eucalyptus urophylla x Eucalyptus camaldulensis, and the others, from the hybrid of E. urophylla x Eucalyptus grandis, all of which are minicutting source courtesy of a nursery in the region. The experiment was a completely randomized block design, as the area is homogeneous. Biometric evaluations consisted of measuring the BD (base diameter), total height and survival at six and 10 months of age. In September 2014, 20 newly mature leaves of every tree were collected from branches located halfway up the canopy, addressed to the quarter cardinal points. In this analysis, 10 trees of each working area of the plots, of each treatment, formed 16 composite samples for the analysis of macro- and micronutrients. Once collected, the leaves were placed in paper bags and sent for laboratory analysis. Hybrids showed no differences in the concentration of Fe, Mn and B (P> 0.05). The hybrid VM1 exhibited higher concentrations of K, Ca, Mg, S and N and intermediate concentration of P. Clones of E. camaldulensis x E.urophylla presented higher survival, height and diameter than clones of E. urophylla x E. grandis. There were differences between treatments for the height at six and 10 months after planting. For the base diameter, there was no significant difference at six months, but at 10 months, a significant difference was detected between treatments. The differences identified in this study for height growth, nutritional status, base diameter and survival in the seedling stage suggest the possibility of selecting genotypes of this crop for the region.   Key words: Development, genotypes, survival, clone, Eucalyptus.