Effects of different rootstocks, and degree of psylla infestation on leaf curl in young pear trees
AuthorsW. H. Griggs
D. D. Jensen
B. T. Iwakiri
J. A. Beutel
Authors AffiliationsWilliam H. Griggs is Professor of Pomology and Pomologist, Department of Pomology, University of California, Davis; Dilworth D. Jensen is Professor of Entomology, Department of Entonmlogy and Acarology, U. C., Berkeley; Ben T. Iwakiri is Laboratory Technician IV, Department of Pomology, U. C., Davis; James A. Beutel is Extension Pomologist, U. C., Davis.
Hilgardia 21(10):16-20. DOI:10.3733/ca.v021n10p16. October 1967.
Differences in pear varieties, source of scion wood, and kind of rootstock had little effect on the incidence of leaf curl in these tests. Psylla are evidently the vectors of curl and there appears to be little hope of controlling the disease through selection of propagating material, unless psylla are excluded. If not infected in the nursery row, many pear trees may quickly become infected in the young orchard even under the best commercial spray program.
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