Location: Northwest Irrigation and Soils ResearchTitle: Beet curly top resistance in USDA-ARS Kimberly germplasm lines evaluated in Idaho, 2017 Author
Submitted to: Plant Disease Management Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/1/2018
Publication Date: 8/27/2018
Citation: Eujayl, I.A., Strausbaugh, C.A. 2018. Beet curly top resistance in USDA-ARS Kimberly germplasm lines evaluated in Idaho, 2017. Plant Disease Management Reports. 12:CF152.
Interpretive Summary: Curly top in the semiarid production areas of the United States is caused by Beet curly top virus and vectored by the beet leafhopper. Resistant sugar beet cultivars became available in the 1930s prior to which curly top almost eliminated the sugar beet industry in the western United States. However, resistance is typically low to intermediate in commercial cultivars and has a tendency to be associated with lower yield potential. Thus, novel sources of resistance need to be identified and incorporated into commercial cultivars. Thirteen sugar beet lines were screened for resistance to curly top. Several lines performed very well and will be investigated further. The results and germplasm will be accessible to interested parties through the USDA-ARS, NPGS GRIN database (http://www.ars-grin.gov/npgs/index.html). These germplasm lines will be released to the general public, so they can be utilized to improve curly top resistance in commercial sugar beet cultivars.
Technical Abstract: Curly top caused by Beet curly top virus is a widespread disease problem vectored by the beet leafhopper in semiarid sugar beet production areas. Host resistance is the primary defense against this problem, but resistance in commercial cultivars is only low to intermediate. In order to identify novel sources of curly top resistance, 13 sugar beet lines were screened in a disease nursery in 2017. The lines were arranged in a randomized complete block design with six replications. A curly top epiphytotic was created by releasing six viruliferous beet leafhoppers per plant at the four- to six-leaf growth stage on 14 Jun. Foliar symptoms were evaluated on 6 Jul using a scale of 0-9 (0 = healthy and 9 = dead) in a continuous manner. Curly top symptom development was uniform and no other disease problems were evident in the plot area. The checks performed as expected for both the visual rating and ELISA. Based on both visual ratings and ELISA, KDH4-9 (PI683513) and KDH13 (PI663862) performed the same as the resistant check. All the KDH13 progenies (crossed to susceptible parental lines) had moderate visual ratings, while two of the progenies (KDH13/EMS9 and KDH13/19-19) had ELISA values that were not different from the resistant check. KDHEMS09 is new line that had very low virus accumulation. These results and germplasm information will be accessible through the USDA-ARS, NPGS GRIN database (http://www.ars-grin.gov/npgs/index.html). These germplasm lines will be released to the general public, so they can be utilized to improve curly top resistance in commercial sugar beet cultivars.