ILOILO City — Pest and disease pressure in rice fields across Western Visayas remained generally low to moderate during the July to December 2025 cropping season, with risks peaking only at mid-season and easing toward harvest, according to the Department of Agriculture’s (DA) Regional Crop Protection Center (RCPC).
The assessment, based on monitoring of 201 rice fields across the region, showed that pest and disease incidence increased during the wet and reproductive stages of rice growth — particularly from August to October — before declining from November to December, a pattern considered typical during periods of high moisture and dense crop growth.
“We are pleased to present the summary of July to December 2025 Regional Rice Pests and Disease Monthly Bulletin,” the RCPC said, noting that the report aims to guide rice farmers, local government unit (LGU) extension workers, and other stakeholders in strengthening Integrated Pest Management (IPM) practices.
Disease trends
The bulletin showed that rice diseases gradually increased from July to September, peaked around September to October, and then declined sharply by November, with brown spot recording the highest incidence during the peak months — often linked to nutrient imbalance and prolonged leaf wetness.
Sheath blight also rose in September due to dense canopies and high humidity but later declined, while bacterial leaf blight and bacterial leaf streak remained low yet persistent, with slight increases toward December. Leaf blast and neck blast stayed at minimal levels, indicating effective field resistance or sound crop management.
Disease pressure was highest from maximum tillering to panicle initiation, though proper spacing, balanced fertilization, and early monitoring helped prevent severe outbreaks.
Insect pests, weeds, and rats
Insect pest incidence followed a similar trend, staying low early in the season before peaking mid-season and tapering off afterward.
Stem borers emerged as the most significant concern, with whitehead symptoms increasing steadily and peaking in October and December, while deadheart damage was most evident in October.
Rice bugs slightly increased toward December during grain-filling, but major sucking pests such as BPH, GLH, RBB, and RGB remained very low, avoiding hopper outbreaks.
Weed cover was highest in September during the vegetative phase, declined toward November, and slightly rose again in December as new field establishment resumed.
Rat injury stayed low throughout the semester, with only a minor spike in September, indicating that early control measures were effective.
The monthly bulletin was generated under the Pest and Disease Risk Identification and Management (PRIME) Project, which provides early warnings and management advisories to help farmers sustain crop productivity and prevent large-scale pest outbreaks./PN
