A recent study from the Philippine Rice Research Institute (PhilRice) found that biopesticides or organic pesticides are effective in managing rice pests and diseases.
The study, titled “Bio-pesticides: Pest management in rice,” conducted by PhilRice Isabela and the Department of Agriculture (DA) Northern Cagayan Experiment Station, proved that, aside from vegetables, biopesticides can also be used for paddy rice.
“Often, biopesticides are used in vegetables. But the study…proved that they can also be effective in managing pests,” PhilRice said.
Biopesticides are compounds derived from plants, animals and microorganisms that contain natural deterrents and antimicrobial properties that help ensure good plant growth. These type of pesticides can also prevent the growth, feeding and the development or reproduction of a pest or pathogen.
Study leader and senior science research specialist from PhilRice Isabela Gracia B. Amar said the team used PSB Rc72H (Mestiso 1) as the test variety in an irrigated lowland area of 3,000 square meters.
They chose bio-pesticides, including the effective microorganism (EM), lactobacilli (lactic) acid, fermented fruit juice (FFJ), biodegradable soap plus water and metarizhium, in conducting the study.
Based on the results of the study, it was found that EM can be used for the management of bacterial leaf blight and bacterial leaf streak; lactic acid for bacterial diseases and flies or maggots; FFJ for green leaf hoppers (GLH), caterpillars and fungal diseases; biodegradable soap plus water for whorl maggots; and metarizhium for leaf folder, whorl maggots, white-backed planthoppers, brown planthoppers and GLH.
Amar said that, among the treatments, EM consistently reduced the number of diseased leaves, while the biodegradable soap reduced lesion length.
The highest reduction on diseased leaves was also observed on plots sprayed with EM and FFJ. Lactic acid was also observed to cause considerable reduction in lesion length and number of diseased leaves.
“This technology will help our farmers, who work in irrigated lowland condition, to increase yield and manage rice pests,” Amar said.
According to Amar, biopesticides only affect target pests and contain less toxic compounds compared to chemical pesticides.
“Biopesticides are also sustainable and environment-friendly because they decompose quickly,” Amar added. However, she said making biopesticides requires a lot of labor. Using it also needs repeated application, as it takes time before it could affect insect pests and diseases.