Location: Sustainable Agricultural Systems Laboratory
Title: Comparison of crown and root inoculation methods for evaluating resistance response of sugar beet cultivars to R. solani AG 2-2IIIBAuthor
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BHUIYAN, ZIAUR - North Dakota State University |
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Lakshman, Dilip |
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DEL RIO MENDOZA, LUISE - North Dakota State University |
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QI, AIMING - University Of Hertfordshire |
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KHAN, MOHAMED - North Dakota State University |
Submitted to: Crop Protection
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 10/3/2022 Publication Date: 10/3/2022 Citation: Bhuiyan, Z.M., Lakshman, D.K., Del Rio Mendoza, L.E., Qi, A., Khan, M.F. 2022. Comparison of crown and root inoculation methods for evaluating resistance response of sugar beet cultivars to R. solani AG 2-2IIIB. Crop Protection. https://doi.org/10.1016/j.cropro.2022.106120. DOI: https://doi.org/10.1016/j.cropro.2022.106120 Interpretive Summary: Sugar beet is an economically important crop and sugar beet crown rot and root rot caused by Rhizoctionia solani is a serious threat to sugar beet production in the US, particularly following the introduction of Roundup Ready® sugar beet (RRSB) cultivars. In this investigation, we compared two methods of Rhizoctonia inoculation, namely the crown inoculation and root inoculation methods to evaluate their efficacies to differentiate resistance responses of seven RRSB sugar beet cultivars in the greenhouse. The results of this study demonstrated that the root inoculation method is optimal for consistent disease rating of germplasm in the greenhouse and indicated that root inoculation may serve as a convenient and accurate method for screening RRSB cultivars in Rhizoctonia resistance breeding programs. This information will be useful to plant pathologists, extension workers and sugar beet farmers. Technical Abstract: Sugar beet (Beta vulgaris L.) is the second major economically important sugar-yielding crop in the world and the US is ranked third in world sugar beet production. Sugar beet crown rot and root rot caused by Rhizoctionia solani (Khün) is a serious threat to sugar beet production and processing. Prior to the adoption of Roundup Ready® sugar beet (RRSB) cultivars, crown rot was a serious problem caused by mechanical tillage operations required for weed control. Following the introduction and large-scale cultivation of RRSB, however, crown rot was reduced but root rot became severe. This necessitated reassessment of screening methods for development of Rhizoctonia resistant cultivars. In this study two inoculation methods, viz. crown inoculation and root inoculation, were evaluated for development of Rhizoctonia root rot, aimed at their efficacy to differentiate the reaction of sugar beet cultivars. The results of this study demonstrated that the root inoculation method is optimal for consistent disease rating of the germplasm in the greenhouse. It was concluded that use of root inoculation method is convenient and accurate for screening of RRSB cultivars in a resistance breeding program. |