D. Moreti et al., ESTIMATES OF GENETIC-PARAMETERS AND GAINS EXPECTED FROM SELECTION OF JUVENILE CHARACTERS IN RUBBER TREE PROGENIES, Pesquisa agropecuaria brasileira, 29(7), 1994, pp. 1099-1109
The objective of this paper was to estimate quantitative genetic param
eters for growth and yielding characters in juvenile half-sib progenie
s of rubber trees [Hevea brasiliensis (Wild ex. Adr. de Juss.) Mull. A
rg.]. Seventeen genotypes were randomly selected from a 35-years-old a
siatic base population established in the Experimental Center of Campi
nas, SP, Brazil. Open pollinated seeds were collected and planted at t
he Experimental Station of Pindorama under randomized complete blocks
design. The characters studied were: yield folowing Hamaker-Moris-Man
(HMM) test (PPB), girth at 50 cm from the ground (CCC), bark thickness
(ECC), total number of latex vessels rings, density of latex vessels
per 5 mm per ring averaged over all rings (DEN), diameter of the latex
vessel rings (DIA), average distance between consecutive latex vessel
rings (DMA), crown evaluation (ACP), leaf area (AFO) and leaf petiole
lenght (CPE). Results indicated significant differences for yield, ba
rk thickness and girth. Also the different types of heritabilities wer
e greater for yield, bark thickness and girth. The genetic gain estima
tes for selection among and within the progenies showed considerable g
enetic advances for the studied characters, revealing the possibility
of successful selection.