The 32nd report of the National Dalbulus maidis Monitoring Network with catch data collected between November 30 and December 15, 2025 shows that early corn has already passed the period of susceptibility to Spiroplasma and the basic corn growing areas are stable and the vector has been practically not detected. Despite some specific outbreaks in endemic areas and in Corrientes that require particular attention, the outlook for late corn is also excellent.
In the NOA endemic zone, the leafhopper remained absent in 48% of monitored sites, while in 36% of traps captures were at minimum levels (1 to 4 adults per trap). The nerve centers recorded in previous reports continued to occur, particularly in Alto Verde (Tucumán). Only 9% of the traps were located on plots with maize (generally maize and seed), as the region is characterized by late summer sowing.
In the NEA, the other endemic region, 55% of sites remained without detections of Dalbulus maidis and 13% recorded the lowest capture rate. However, with the increase of the middle and high categories in certain places, especially in Comandante Fontana (Formosa), a period of population growth begins. 40% of traps in this region are installed on corn plants, which promotes early detection.
On the coast, Dalbulus maidis was not detected at 65% of monitored sites and at 16% catches remained at the lowest levels. However, at some locations with corn in advanced reproductive stages, there were slight increases in the intermediate category. It is worth remembering that 97% of traps in the region are installed on corn plants.
In the Central-North region, 85% of locations had no detections, while 12% recorded the lowest catches. 87% of traps in the region are in plots of corn.
In the central south, too, no Dalbulus maidis was detected in 97% of the locations; in the remaining areas only the minimum amount was detected. 86% of the traps were placed on corn.
For the network’s experts, it is crucial to maintain monitoring throughout the year, both with traps and crop observations, both in early maize growing areas (especially when interventions have already stopped) and in late growing areas, where volunteer maize (“guachos”) can favor the survival and proliferation of the pest and its pathogens.
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