Foliar sprays of 0.025M and 0.04M solutions of K2HPO4 and KH2PO4 + KOH (both plus Triton X-100) and commercial systemic fungicides inhibited development of powdery mildew fungi on fruit clusters, flower clusters, fruits and leaves of field-grown grapevines, mango and nectarine. The effectiveness of phosphates in controlling powdery mildew on berries of Chardonnay grapevines was similar to that of the systemic fungicide pyrifenox (Dorado 480 EC). However, the systemic fungicides diniconazole (Marit 12.5% WP), myclobutanil (Sisthane 12E) and penconazole (Ophir), were more effective in controlling the disease on inflorescences of mango and fruits of nectarine, respectively, than either phosphate. Alternating treatments of phosphate salt with each of these fungicides, however, enhanced the inhibitory effect against the fungus in each crop. With the exception of young, newly developed nectarine leaves, these phosphate solutions were not phytotoxic to plant tissue. The inhibitory effectiveness of phosphate salts makes them useful 'biocompatible' fungicides and ideal foliar fertilizers for field application for disease control.
Bibliographical noteFunding Information:
Contribution from the Agricultural ResearchO rganiza-tion, The Volcani Center, Bet Dagan, Israel. No. 1316-E, 1994s eries.T his work was supportedi n part by the Ministry of Sciencea nd Technology, the Stateo f Israel. Project No. 3583-2-92.
- disease control
- foliar fertilizers
- systemic fungicides
ASJC Scopus subject areas
- Agronomy and Crop Science