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The use of wood as a bioenergetic source requires knowledge of its technical properties. The rubber tree Hevea brasiliensis has an economic life cycle of 25 to 30 years in Brazil. It is used for extracting rubber and generating residual wood for fuel. Our goal was to characterize the wood quality of 10 clonal progenies as a source of raw material for bioenergy. Ten clonal progenies of 12-year-old Hevea brasiliensis from an experimental planting in Selvíria municipality were evaluated. Three trees per clone were evaluated for individual properties of Higher Heating Value, immediate chemical analysis, chemical composition, fiber dimensions, thermogravimetric analysis of wood under nitrogen atmosphere and Fourier Transform Infrared Spectroscopy analysis. We highlight clone IAC 311 for fuel because it presents elevated Higher Heating Value and fixed carbon and less volatile material. However, the other genetic materials studied also meet the specifications for energy use and can be highly viable given their physical, chemical, energy, and thermal properties. [ABSTRACT FROM AUTHOR]

The present study aimed at estimating genetic parameters and variability among and within provenances for silvicultural traits of Handroanthus vellosoi (Toledo) Mattos, in provenances and progenies test stands, located at the Luiz Antônio Experimental Station (São Paulo State, Brazil). The test was established in the compact family block design, with two provenances (allocated in the plots), six replicates and sub-linear plots of five plants, totalizing 35 progenies. Diameter at breast height (DBH), plant height, cylindrical volume, stem form and survival at 24 years of age were evaluated. Significant differences among the provenances were observed only to the trait stem form. The analysis of deviance showed significant differences among progenies for the joint analysis of the provenances (experimental population), suggesting that the population has high genetic variation and indicating the possibility of genetic improvement by selection of the best progenies. Heritability estimates in individual and family level ranged from low to moderate (26% for DBH, 32% for plant height, 24% for cylindrical volume, 27% for form and 36% for survival), confirming the possibility of genetic improvement by selection and that the provenances have potential to respond to the pressure of natural selection. [ABSTRACT FROM AUTHOR]