Measures to control brown planthopper in rice
Brown planthopper (Nilaparvata lugens) is one of the most dangerous pests affecting rice plants in Vietnam. Besides causing direct damage, brown planthopper also acts as a vector for rice yellow dwarf and rice leaf curl diseases, which are extremely dangerous and have caused widespread outbreaks in Vietnam a few years ago.
To minimize the damage caused by brown planthoppers, a combination of measures must be applied synchronously and rationally within the Integrated Pest Management (IPM) process, such as: avoiding continuous sowing (if possible, allow the land to rest for about 20-30 days between two rice crops); maintaining clean fields; using planthopper-resistant varieties;
Avoid sowing too densely (sow 100-120 kg of seeds/ha, or 70-80 kg/ha if sowing in rows); sow simultaneously and in a concentrated manner across each field or area, following the schedule directed by the local plant protection agency to avoid pests;
Apply fertilizer in a balanced ratio of nitrogen, phosphorus, and potassium; avoid using broad-spectrum pesticides at the beginning of the season. To protect the population of natural predators in rice fields, regular field inspections to detect and promptly spray insecticides to control rice planthoppers are indispensable, and often decisive, measures.
Regarding pesticides, there are currently many types of pesticides on the market for controlling rice pests and diseases. However, for brown planthoppers, according to the experience of many farmers in the Mekong Delta over the past few years, the following pesticides have proven to be very effective:
1- Schezgold 500WG: This is a specific insecticide for brown planthoppers (even those resistant to other insecticides). It has contact and stomach poison effects; it also has systemic and translaminar properties. The insecticide has an immediate effect on the conduction and motor nervous systems of the insects, so even if the planthoppers don't die immediately after infection, they can no longer harm the rice plants.
The insecticide kills both nymphs and adult planthoppers, has minimal impact on natural enemies, and therefore does not cause brown planthopper outbreaks. Regarding dosage, mix 1 packet (15 grams) per 16-liter sprayer, and spray 2 sprayers per 1,000 m². If the planthopper population is high, or the rice field is densely covered, you can spray 2.5 - 3 sprayers per 1,000 m².
2. Comda Gold 5WG: This insecticide has contact, stomach, repellent, and systemic action; it has good adhesion and spreading properties, and is highly effective in controlling pests (even those that have developed resistance to other insecticides).
As a bio-based insecticide, it is less likely to cause resistance in pests; and because it has minimal impact on beneficial insects in rice fields, it does not cause brown planthopper outbreaks. Regarding dosage, use 1/3 of a packet (10 grams/packet) mixed in a 16-liter sprayer, and spray 2.5 - 3 tanks per 1,000 m2.
3. Sairifos 585EC: Due to the mixture of two active ingredients belonging to the organophosphorus and synthetic pyrethroid groups, its pest control effectiveness is greatly enhanced; in addition to contact, stomach, and fumigation effects, the pesticide also repels and inhibits feeding, resulting in very high control efficacy. Regarding dosage, mix 25-30 ml of pesticide per 16-liter sprayer, and spray 2.5-3 sprayers per 1,000 m².
4. Sargent 6G: This insecticide has contact, stomach, and fumigant action, a broad spectrum of activity, and fast, strong insecticidal efficacy. Regarding dosage, Sargent 6G can be applied to the field at a rate of 8-10 kg/ha when rice planthoppers appear. When applying, the field must have a layer of water 3-5 cm deep, and this water level must be maintained for 3-5 days.
In rice fields with tall plants or densely packed rice paddies, it's advisable to divide the rice into strips about 1.5 meters wide so that the pesticide can reach the base of the rice plants, resulting in a higher mortality rate for rice planthoppers.
According to NNVN - LY