000			02146nam a2200193Ia 4500
008			220216s9999 xx 000 0 und d
100			_aMedrado M J S
245		0	_aAnatomical changes in rubber tree cuttings (Hevea brasiliensis clone RRIM 600) in response to different rooting techniques
260			_bScientia Agricola _c1995
300			_a89-95
520			_aClones of Hevea spp are presently grafted on seedilings, because no economic method of producing clonal rootstocks by vegetative means or clonal cuttings has so far been discovered. Because of this, Hevea clones do not exteriorize their maximum genetic potential for latex production. The rooting of clonal cuttings overcomes this problem. However, Hevea is considered a plant with very poor capasity of rooting, in its mature phase. Plants have at the stem base an almost continuous cylinder of lignified tissues, which along with chemical barriers can difficult rooting. At present, rooting problems in some plant species may be overcome by a combination of new techniques as it is the case of total or local etiolation and girdling. This work has the aim to characterize the modifications occured in clonal cuttings of Hevea when subjected to the above mentioned technique, alone or combineed. It was possible to conclude that the girdling of the cutting base from the RRIM 600 clone, as well as its utilization in combination with the other two types of etiolation, promoted drastic alterations in the sheath, as compared to the control. Moreover, girdling promoted the activity of the vascular cambio, which produced a greater number of parenquimatous cells in the phloem, resulting in a discontinuity, of the perivascular fibers sheath. Other alterations elapsed of the girdling were : the division of parenquimatous cells around of the sheath forming meristematic rings and a greater number of lenticells in comparison to the control, which can favour the rooting of the cuttings.
650			_aAdventitious rooting
650			_aAnatomy
650			_aCutting
650			_aHevea brasiliensis
700			_aAppezzato-da-gloria B
700			_aCosta J D
942			_cJS
999			_c54281 _d54281