000			01662nam a2200241Ia 4500
008			220216s9999 xx 000 0 und d
100			_aGoncalves P De S
245		0	_aVariability of the structural characteristics of the bark in the laticiferous system of young rubber (Hevea) trees
260			_bPesquisa Agropecuaria Brasileira _c1995
300			_a649-656
500			_aSource Year: 1996
520			_aThe variability and repeatability of characteristics of the laticiferous system of the bark of 76 3-year-old plants of rubber (Hevea) were studied in Sao Paulo, Brazil. Observations were made on bark thickness (BT), total number of latex vessel rings (NLVR), diameter of latex vessel rings (DIA), density of latex vessel rings per 5 mm per ring averaged over all rings (DD), and average distance between consecutive latex vessel rings (DLVR). Based on the analysis of variance, coefficients of repeatability and genetic gains were estimated for each charecteristic for 2, 3,4 and 5 different height samples taken from the stem of each seedling. The heighest average repeatability values were observed for DLVR and BT, respectively. These highest genetic advances were obtained for BT and NLVR with 4 and 5 samples, respectively. The repetability and genetic gain obtained with 3 bark samples were only slightly less than with 4 and 5 samples, and gave a better progress in the selection.
650			_aBrazil
650			_aGenetic gain
650			_aHevea
650			_aLatex vessel rings
650			_aLaticiferous system
700			_aBortoletto N
700			_aMartins A L M
700			_aUtida R De C
856			_uAEDR
942			_cJS
999			_c72096 _d72096