The Philippine Rice Research Institute (PhilRice) has issued pest management advisories following a report by the Bureau of Plant Industry (BPI) identifying pests potentially endangering rice production in the first quarter, based on historical data spanning from 1993 to 2023.

The pests listed by the BPI, including rodents, brown planthoppers, rice stem borers, bacterial leaf blight, and rice black bugs, pose threats such as destructive feeding habits, sap-sucking, stem boring, bacterial disease, and direct damage to rice crops.

Data show that Region 3 is expected to be affected by the five pests. Regions 5, 6, and 7 are also projected to experience attacks from these pests with most of the provinces identified as potential infestation sites.

Experts recommended practicing field sanitation and fallow period, synchronizing planting schedules, timing control applications, and regularly monitoring fields to effectively mitigate pest infestations.

“Rodents, which threaten six provinces in the Bicol Region and Central Luzon, are known for their incessant gnawing behavior, driven by the continuous growth of their incisors from nine days after birth throughout their lifespan,” crop protection expert Leonardo V. Marquez said.

These provinces include Camarines Sur, Sorsogon, Albay, Catanduanes, Masbate, Camarines Norte in Bicol and Aurora, Pampanga, Bulacan, Nueva Ecija, Tarlac, Bataan in Central Luzon.

To control rat populations, experts recommend setting up a community rat trap barrier system, hunting, field sanitation, flooding, observing fallow periods to disrupt rat habitats and food sources, and synchronizing planting to limit food availability for rats.

Farmers in the provinces of Regions 3 and 8 are also advised to monitor infestations of the brown planthopper (BPH), which sucks the sap of rice plants, leading to wilting of shoots or the entire plant. The persistent sucking and excretion of BPH on rice plants promote mold growth.

Marquez shared that a high number of 100 or more BPH per plant can cause hopper burn or rapid drying of the rice plants. Farmers are encouraged to refrain from excessive nitrogen usage, to flood fields as necessary, and to apply insecticides judiciously.

Central Luzon’s seven provinces may also be infested with rice stem borer, which causes deadheart, affecting the central shoot of the plant and whitehead, characterized by the turning of panicles to white.

Cutting leaf tops to reduce egg layover and field release of the egg parasitoid Trichogramma japonicum are among the options in managing stem borer infestation.

Farmers in Regions 3, 5, and 6 are also advised to monitor bacterial leaf blight, which could lead to a yield reduction of 10-60%. They are also advised to maintain good drainage and avoid excessive nitrogen use.

While the rice black bug (RBB) may only affect a few areas in Western Visayas and Central Luzon, experts warn that its threat should not be underestimated as it can reduce yield by 15-23% for every 10 RBBs detected per rice stem.

Recommendations for managing RBB include light trapping, increasing water levels, herding ducks, plowing under heavily infested fields, and plowing after harvesting.

Farmers can contact their local municipal or city agriculture office, PhilRice, or BPI for assistance in implementing integrated pest management strategies, including cultural, biological, and chemical controls, for timely intervention.