University of California

Susceptibility of almond leaf to Coryneum blight, and evaluation of helicopter spray applications for disease control


J. M. Ogawa
W. E. Yates
W. W. Kilgore

Authors Affiliations

J. M. Ogawa was Associate Professor of Plant Pathology and Associate Plant Pathologist in the Experiment Station, Davis; W. E. Yates was Associate Professor of Agricultural Engineering and Associate Agricultural Engineer in the Experiment Station, Davis; W. W. Kilgore was Lecturer, Department of Food Science and Technology, and Assistant Biochemist in the Agricultural Toxicology and Residue Research Laboratory, Davis.

Publication Information

Hilgardia 35(19):537-543. DOI:10.3733/hilg.v35n19p537. October 1964.

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Coryneum beijerinckii conidia germinated equally well on both surfaces of almond leaves. The underside of leaves was more prone to infection than the upper side and deposits on both surfaces were required for effective disease control. Helicopter spray applications with captan gave excellent disease control, provided the spray droplet size and air speed were reduced from those normally used in commercial helicopter spray applications. The finer spray droplets and slower helicopter speed resulted in considerably more captan deposit on both surfaces of leaves and glass slides. The amount of this deposit was determined by chemical analyses and its fungitoxicity was determined by bioassay with conidia of C. beijerinckii.

Literature Cited

Kilgore W. W., Yates W. E., Ogawa J. M. Evaluation of concentrate and dilute ground air-carrier and aircraft spray coverages. Hilgardia. 1964. 35:527-536. DOI: 10.3733/hilg.v35n19p537 [CrossRef]

Ogawa J. M., Yates W. E. Effect of volume and variation in droplet size of spray applications from an air-carrier sprayer on control of three almond diseases. Plant Disease Reptr. 1962. 46:614-15.

O’Reilly H. J. Relative efficiency of airplane and ground application of sprays in controlling almond shot-hole disease. Phytopathology. 1957. 47:530

Ogawa J, Yates W, Kilgore W. 1964. Susceptibility of almond leaf to Coryneum blight, and evaluation of helicopter spray applications for disease control. Hilgardia 35(19):537-543. DOI:10.3733/hilg.v35n19p537
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