Effects of Some Plant Growth Promoting Rhizobacteria (PGPR) on Graft Union of Grapevine

摘要

In this study, effects of topical applications of three plant growth promoting rhizobacteria (PGPR) strains (Pseudomonas BA8, Bacillus BA16 and Bacillus OSU142) on graft union were evaluated in terms of success rate, callusing rate, callusing degree and full callusing rate on four different rootstock-scion combinations including 41B-Beyaz gavus, 41B-Italia, 5BB-Beyaz gavuS and 5BB-Italia. The results showed that in general all of the bacterial strains had significant effects on all parameters testedin all rootstock-scion combinations compared with the control. Application of Pseudomonas BA8 in 41B-Beyaz gavus, Bacillus OSU142 in 41B-Italia, Pseudomonas BA8 in 5BB-Beyaz gavus, and Bacillus BA16 and Bacillus OSU142 in 5BB-Italia combination increasedthe success rate (83.3%, 93.3%, 80.0% and 86.7%, respectively) compared with the control (23.3%, 80.0%, 60.0% and 70.0%, respectively). Application of PGPR also increased the callusing rate, callusing degree and full callusing rate in all rootstock-scion combinations compared with control.Among the bacteria strains tested, Pseiidomonas BA8 was the most effective PGPR strain which can be used for graft union of grapevine grown in commercial, sustainable or organic agriculture.