ILOILO City — Brown spot continued to be the most common rice disease in Western Visayas in June, although the overall pest situation remained under control as most rice fields across the region had already been harvested, the Department of Agriculture (DA) Regional Crop Protection Center (RCPC) reported.
The RCPC’s June 2026 Rice Monthly Pest Bulletin showed brown spot affecting 7.18 percent of monitored rice fields, the highest among all recorded diseases and continuing a steady rise from the previous two months.
Agriculture experts said the gradual increase could be linked to nutrient-poor soils, crop stress, older rice plants and humid weather conditions associated with intermittent rains.
Despite the upward trend, the agency emphasized that brown spot has not reached epidemic proportions but warned that farmers should remain vigilant because the disease can reduce grain quality and harvests if left unmanaged.
The findings were based on pest surveillance conducted under the Pest and Disease Risk Identification and Management (PRIME) project, which regularly monitors selected rice-growing communities in Western Visayas.
The June assessment covered 153 monitoring sites, but only 17 fields still had standing rice crops. Nearly 90 percent of the monitored farms had already completed harvest or were waiting for the next cropping cycle, reducing available host plants for pests and diseases.
Aside from brown spot, disease incidence remained minimal across the region. Leaf blast registered 0.38 percent, while bacterial leaf blight dropped to 0.24 percent, indicating that existing disease management practices and prevailing weather conditions continue to limit their spread.
Insect infestations also stayed at relatively low levels.
Stem borer damage, measured through deadheart and whitehead symptoms, averaged 1 percent, while rice bug occurrence was placed at 0.52 percent.
Although these levels remain below economic damage thresholds, the RCPC advised farmers to continue monitoring their fields, particularly during critical crop growth stages and in late-maturing rice areas where rice bugs can still affect grain development.
The bulletin also noted that weed cover averaged 5.15 percent, a decline from May but still slightly exceeding the recommended management threshold. The agency said timely weed control remains necessary to prevent unnecessary competition for water, nutrients and sunlight.
Meanwhile, rat damage averaged only 0.38 percent, reflecting generally low rodent activity. Even so, agriculture officials encouraged communities to sustain coordinated rodent control efforts before populations increase in succeeding planting seasons.
Among the provinces, Iloilo posted the highest brown spot incidence at 7.18 percent. The province also recorded 5.15 percent weed cover, 1 percent stem borer injury, 0.52 percent rice bug incidence, and 0.38 percent for both rat damage and leaf blast.
In Aklan, weed cover reached 3.33 percent, while rice bug incidence stood at 0.67 percent.
Both Capiz and Guimaras reported 5 percent weed cover, while Antique had no pest records submitted during the June monitoring period.
The RCPC said the latest surveillance points to a generally stable pest situation across Western Visayas, with no widespread outbreaks detected.
It urged farmers to continue regular field inspections, practice balanced fertilization and proper water management, adopt integrated pest management strategies, remove weeds early, and sustain community-based rodent control measures to protect rice production in the coming cropping season./PN
