The high level of copper (Cu) accumulation in the soil, the risk of surface water contamination,
and the potential public health problems due to Cu entering the food chain have raised concerns
on the use of Cu compounds in agriculture, including olive growing. As a consequence, there is
worldwide regulatory pressure on agricultural systems to limit the use of Cu compounds. Hence, a
field trial was carried out to evaluate the effectiveness of low copper containing chemicals to control
olive leaf spot (OLS) disease caused by Venturia oleaginea. The trial was conducted in 2021 in an
olive (cv. Nabali Baladi) grove in Palestine. Copper complexed with lignosulphonate and gluconate
(Disper Cu Max®) and the self-defense inducer Disper Broton GS® were evaluated and compared to
dodine and the traditionally and frequently used copper hydroxide. In addition, untreated trees were
used as the control. Treatments were made in March, July, and August. In March 2021, leaves grown
in 2020 were present and 100% infected. V. oleaginea infections caused defoliation in untreated and
treated olive trees with varying degrees of intensity: the Control had the most defoliation, followed
by copper hydroxide and Disper Cu Max®, whereas dodine and, in particular, Disper Broton GS® had
the least. All treatments reduced symptomatic leaves but their efficacy varied significantly: copper
hydroxide was the least effective, Disper Cu Max® was intermediate, dodine and, mainly, Disper
Broton GS® were the most effective. Overall, the results are promising since Disper Cu Max® and
Disper Broton GS® were able to significantly reduce OLS damage and the amount of copper used
for treatments.

Title

AGRICULTURE

Publisher

MDPI

Publisher Country

Switzerland

Indexing

Thomson Reuters

Impact Factor

3.4

Publication Type

Prtinted only

Volume

12

Year

2022

Pages

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