The density of small leaf rollers is many times higher than the same period in many years.

Tuesday, August 15, 2023 | 15:45:55

276 views

That was the information given at the conference on implementing pest prevention and control work to protect crop production in 2023 organized by the Department of Agriculture and Rural Development on the morning of August 15.

Agricultural staff of Hung Ha district check the density of leaf rollers in the field.

In the 2023 crop, the whole province will plant 75,033 hectares of rice, of which high-quality rice varieties account for 47% of the area, high-yield rice varieties account for 52.34% of the area, and the rest are hybrid rice varieties. Currently, rice is in the final stage of tillering to panicle formation. It is expected that the winter-spring rice will flower from September 5 to 20.

According to the investigation of the Department of Crop Production and Plant Protection, in the 2023 crop, the leaf roller appeared earlier, lasted longer, was widely distributed and had a much higher density than in the 2022 crop and the same period in many years. The peak of the 6th generation of leaf rollers was prevented and eliminated; the peak of the 6th generation of larvae hatched from August 18 to 25. It is forecasted that the average density of larvae is 100 - 200 individuals/ ^m2 , in some places 300 - 400 individuals/ ^m2 , locally 700 - 900 individuals/ ^m2 to 1,000 individuals/ ^m2 . This is a widespread outbreak of larvae, causing serious damage to flag leaves and functional leaves on seasonal rice fields. In addition, other pests and diseases such as two-spotted stem borer, planthopper, black-striped dwarf disease, bacterial leaf blight, rice blast disease... appear and cause local damage.

Faced with the complicated developments of the leaf roller, the agricultural sector has requested the Provincial People's Committee to issue an urgent dispatch directing localities, departments and branches to organize a good campaign to prevent and control pests to protect the winter-spring rice crop from August 20 to 24, ensuring that no locality or unit is subjective and allows the leaf roller to develop, causing serious damage and reducing the yield of the winter-spring rice crop. In addition, in areas with high density of stem borers, rice in August must combine spraying to prevent and control stem borers. The agricultural sector also recommends that farmers keep the water level in the field from 3 - 7cm at the stage of rice panicle formation to facilitate panicle formation, increasing the effectiveness of pest prevention and control. Do not use urea and foliar fertilizers for the purpose of raising panicles and grains, which increases the level of damage caused by pests, especially bacterial leaf blight and bacterial stripe at the end of the crop.

Ngan Huyen

Source