SPRAY APPLICATION TECHNIQUES IN BLACK CURRANT PLANTATIONS OF TWO SYSTEMS

Two air assisted sprayers: conventional radial-flow sprayer and directed air-stream sprayer were used in black currant row system plantation in order to compare coverage uniformity and biological efficacy of different spray volumes (260, 400 and 600 l/ha) and pesticide doses (standard and reduced by 30%). For conventional sprayer the reduction of spray volume caused a significant decrease of spray coverage in all combinations, while the other sprayer caused no significant difference in coverage between two lower spray volumes.
The biological response was not so obvious in respect to population of twospotted spider mite (Tetranychus urticae). Depending on season and acaricides used, the directed air-stream sprayer gave better or worse control of mites and no significant differences in mile population between spray volumes nor chemical doses.
Infection intensity with currant rust (Cronartium ribicola), in average was lower, and no significant effect of spray volume was observed for directed air-stream sprayer.

Two sprayers: conventional boom without and with air assistance were used at spray volumes 250 and 500 l/ha in high density (solid field) black currant plantation.
The coverage was evaluated at three canopy levels.
Air assistance considerably increased the spray coverage at all canopy levels on both upper and lower sides of targets and enhanced the spray distribution uniformity within the bushes.

VI International Symposium on Rubus and Ribes

G. Doruchowski, B.H. Labanowska, W. Goszczynski, A. Godyn

https://doi.org/10.17660/ActaHortic.1993.352.77