The Impacts of Tumorigenic and NontumorigenicAgrobacterium vitisStrains on Graft Strength and Growth of Grapevines

Abstract

The effects of tumorigenic and nontumorigenic strains of Agrobacterium vitis on graft strength and growth of grapevines was studied. A procedure was developed for inoculating graft interface surfaces with A. vitis and for measuring the force required to break grafts at different time points. Cuttings were soaked in an aqueous suspension of bacteria, about 106 CFU/ml, and bacteria were spread onto the graft interface during the grafting procedure. Tumorigenic strain CG49 caused reduced bud germination and increased callus (crown gall) at the graft union and at the base of cuttings at 30 days postinoculation (dpi) and significantly reduced shoot growth by 60 dpi whereas, at the same time points, nontumorigenic strain F2/5 inhibited callus formation but did not affect bud germination or shoot growth. Graft strength was enhanced at 30 dpi with CG49, presumably because the crown gall callus served to secure the union; graft strength was weakened by F2/5 over the same period. Between 30 and 60 dpi, the greatest increase in graft strength was observed in the water control. Following graft union inoculations, the A. vitis population increased more than 1,000-fold within 5 days.

Crown Gall Disease of Fruit Trees, Berry Plants and Ornamentals Caused by Agrobacterium Spp.

“…Среди средств, проходивших испытания, можно назвать паурин -биопрепарат на основе P. fluorescens CR 330D, который применяется для профилактики заболевания в опытных питомниках в Молдове (Леманова, Магер, 2011). Имеются положительные отзывы по применению для профилактики заболевания в РФ и за рубежом целого ряда невирулентных штаммов A. radiobacter (Магер, 1991;Hao et al 2018). Большая часть испытанных в полевых и лабораторных условиях антагонистов агробактерий принадлежали Paenibacillus spp.…”