Submitted to: Pecan Grower
Publication Type: Trade Journal
Publication Acceptance Date: 9/20/2016
Publication Date: 11/1/2016
Citation: Bock, C.H., Grauke, L.J., Conner, P., Burrell, S.L., Hotchkiss, M.W., Boykin, D.L., Wood, B.W. 2016. Scab susceptibility of a provenance collection of pecan in in the southeastern USA. Pecan Grower. 27(5):42-55.

Interpretive Summary:

Technical Abstract: Pecan scab is the most economically destructive disease of pecan in the Southeast US. It is spread in rain and is widespread in the Southeast where conditions conducive to epidemics. A provenance collection of pecan from 19 locations representing the native range of the tree is located in Byron, Georgia, and was assessed for pecan scab severity in 1998, 2013 and 2014. There were significant differences among the 19 provenances with those from wetter locations (generally north of Texas) having a greater proportion of scab resistant trees, while provenances from the drier southern areas (Texas and Mexico) tended to be the most susceptible to scab. The association with rainfall was born out by correlation analysis. Despite using different methods, there was generally good agreement among years in regard to severity of disease on individual trees. In conclusion, trees from areas with greater annual rainfall (generally more norther locations) are most likely to provide valuable and diverse sources of resistance to scab. The provenance collection contains a range of scab-resistant genotypes from diverse locations that can contribute to genetic improvement regarding scab resistance.