Cold Argentina weather seen slowing leafhopper outbreak in corn crop

BUENOS AIRES, May 27 (Reuters) - Cold temperatures across much of Argentina's farming heartland over the weekend will help slow a severe leafhopper insect outbreak that has damaged the country's corn crop, the Rosario grains exchange said on Monday.

Argentina is the world's third-largest corn exporter, but the current crop has suffered from an explosion in the leafhopper population. The insects spread disease and eat sap, stunting a plant's growth and turning leaves yellow.

The leafhopper outbreak has resulted in the Rosario exchange cutting its forecast for the current corn harvest by 20% since the beginning of the season to 47.5 million metric tons.

"Low temperatures spread not only in the center of the country but also to the north," the exchange said in a report. "In these areas, temperatures below 4 degrees Celsius (39.2 degrees Fahrenheit) were recorded, with frost in several places."

The leafhoppers, whose population had surged due to a dearth of freezes during the previous corn cycle, do not tolerate temperatures below 4 C.

"Below-zero temperatures and frost help reduce the presence of this pest," the exchange said.

As of Thursday, farmers had harvested 28.2% of the corn planted area for the 2023/24 marketing year, according to the Buenos Aires grains exchange.

(Reporting by Maximilian Heath; Writing by Brendan O'Boyle; Editing by Rod Nickel)