PRODUCER FIGHT AGAINST CROWN GALL DISEASE.

Agrobacterium vitis-induced crown gall disease (tumor) is the greatest problem in vineyards. Much proceed has not been achieved in fight against crown gall disease. Producers either totally stub out the vines from already established vineyards or keep viticulture activities with palliative measures. This study was conducted for two years to investigate the effects of shoot regeneration on yield, quality and development of A. vitis-infected grapevines. Initially the grapevines with morphologic A. vitis symptoms were determined in experimental vineyard. Then, deep pruning (cutting) was performed 10-15 cm below the tumorous sections of the stems in 2010, 2011 and 2012 and shoot regeneration was stimulated. Data were gathered about yield, quality (number of clusters, cluster weight, berry weight, must TSS content, TA, maturation index) and vine growth parameters (number of buds, number of shoots, burst ratio, pruning weight). About 15% less development was observed in grapevines with shoot regeneration treatments in 2012, 25% in grapevines with shoot regeneration treatments in 2011 and 37% in grapevines with shoot regeneration treatments in 2010. With shoot regenerations in 2012, 2011 and 2010, yields decreased respectively by 49, 58 and 66%; cluster weights decreased respectively by 32, 37 and 47% and berry weights decreased respectively by 14, 19 and 21%. [ABSTRACT FROM AUTHOR]