Proactive control of rice leaf roller pests

(Baonghean)Over 400 hectares of summer-autumn rice crops in Nghia district have been affected by pests and diseases, primarily small leaf-rolling caterpillars. In response, the District Department of Agriculture and the Plant Protection Station are coordinating with local authorities to direct farmers to implement timely control measures to ensure the rice plants can develop normally.

Since July 4th, small rice leaf rollers have begun appearing in many rice fields in Nghia Dan district. This type of caterpillar has a long life cycle, and if not controlled promptly, it will significantly affect the growth and yield of rice later on. Next to his rice field, Mr. Le Van Nhan, from Son Hai hamlet (Nghia Loc commune), is spraying pesticides before the caterpillars form cocoons. Mr. Nhan said: "My family cultivates over 1 sao (approximately 1000 square meters) of summer-autumn rice and 3 sao of main crop. Currently, the summer-autumn rice crop, which is in the tillering stage, is being damaged by the second generation of small rice leaf rollers. To prevent the infestation from spreading to other areas, I have bought pesticides to spray."

To date, more than 80 out of 400 hectares of summer-autumn rice in Nghia Loc commune have been infected with small rice leaf rollers, with an average density of 10-15 larvae/m2, and in some areas reaching 20-25 larvae/m2. Mr. Ngo Sy Cuong, Vice Chairman of the People's Committee of the commune, said: After more than two years, this pest has returned to the rice fields of Nghia Loc. For example, in the 2010 autumn-winter crop, the rice yield of the entire commune decreased sharply due to the rice leaf roller infestation.

After agricultural extension officers reported on the pest and disease situation in rice fields, the commune coordinated with the district's Plant Protection Station to hold a meeting with the villagers and develop a timely control plan. Specifically, the commune mobilized motorized pumps from the sugar factory and local residents, requiring families with infected fields to go to the fields for simultaneous spraying. As a result, about 80% of the affected area has recovered, while about 20% remains uneradicated because the villagers have not proactively sprayed according to the commune's schedule.

Mr. Le Van Nhan (Nghia Loc commune) is spraying insecticide to control small leaf-rolling caterpillars.

In Nghia Trung commune, over 220 out of 262 hectares of summer-autumn rice crops were damaged by rice leaf rollers, concentrated in 16 out of 19 hamlets. After compiling data from the hamlets, the commune, in coordination with the Plant Protection Station, conducted training and informed the people about pest control techniques. On July 15th, the commune organized a simultaneous spraying operation on all affected rice fields. Because the pests were in their first instar stage, the impact on the rice plants was not significant, and after spraying, the infected rice crops recovered well.

Mr. Le Cong Tam, Head of the District Agriculture Department, said: Identifying the rice leaf roller as a dangerous pest for rice plants, especially during the late tillering and heading stages, the district has directed communes with affected rice fields to establish steering committees and regularly monitor and promptly assess the pest's development. They then report to the Plant Protection Station and the Agriculture Department for timely guidance and support. For communes with significant damage from the rice leaf roller, such as Nghia Loc, Nghia Khanh, Nghia Trung, Nghia Thinh, etc., the District People's Committee has agreed to allow the Plant Protection Station to supply pesticides to farmers through a trust system, with farmers paying later. At the same time, each commune will develop its own plan and mobilize motorized pumps to organize simultaneous spraying to achieve the highest effectiveness. Thanks to these control measures, the pest situation has been brought under control, and the rice crop in the district is developing well.

Mr. Cuong added that, according to the district's Plant Protection Station's forecast, the first generation of rice leaf rollers will break out in the rice fields on July 25th. To prepare for effective pest control, the commune has broadcast announcements over the loudspeaker to inform all residents. Simultaneously, each hamlet will hold meetings to disseminate knowledge on pest control and prepare all necessary equipment and pesticides so that spraying can be carried out simultaneously when scheduled.

Text and photos: Pham Bang