Assessment of Bion, Two Commercial Bio-products and Other Organic Amendments for Management of Potato Brown-Rot under Field Conditions

The efficacy of using Bion, two commercial bio-products and organic amendments on reduction of potato brown rot and their effect on susceptibility of eight potato cultivars to the disease was evaluated. Field experiments during 2019/20 and 2020/21 growing seasons at Giza governorate, Egypt revealed that all the tested treatments effectively reduced the bacterial wilt under the natural infection. The combination treatments of Bion + Bio-ARC + Bio-Zeid and Bio-ARC + old Balady manure + chicken manure were the highly efficient ones in lowering the infection, being 2.3% wilt, 1.9% infected tubers and 2.0% wilt, 1.4% infected tubers, respectively. Additionally, Mondial potato cultivar was the least susceptible one associated with high rhizospheric microflora content. Using the combination of the resistance inducer Bion (BTH) with two commercial bio-products (Bio-ARC and Bio-Zeid) and two organic manures (Balady and chicken) are promising alternative methods for reducing potato bacterial wilt. Besides, there were remarkable variations in the values of free, conjugated and total phenols of the tested 8 potato cultivars, where Mondial cultivar recorded the highest values, Spunta the lowest values and the other cultivars recorded intermediate values.