Chemical induction of physiological changes during adventitious root formation and bud break in grapevine cuttings

The effects of some terpenoids (isopatchoulenone-rich fraction ofCyperus scariosus oil, C16-guaianolide and thymol), anauxin (IBA) and a combination of terpenoids and IBA were investigated onrooting, sprouting and accompanying biochemical changes in grapevine cuttingsvar. perlette. Treatment of cuttings for 24 h before planting insand pots caused stimulatory effects in terms of number of primary roots,lengthof longest primary root and shoot length, with a concomitant increase in totaldry weight of roots and shoots over control at 60 days after planting stage.Theactivities of peroxidase, polyphenol oxidase and the content of total phenolsdeclined in comparison with the control, hence sparing IAA resulted in enhancedcontents for the induction of adventitious roots. Different terpenoidtreatmentsalso significantly enhanced the chl a, chl b and total chl content in leaves.The levels of total soluble sugars, reducing sugars and proteins also alteredwith these terpenoids. C.S. oil and C16-guaianolide exhibited a better responsein combination with 100 μg ml^sup -1^ IBA, whichsuggests its synergistic effect.[PUBLICATION ABSTRACT]