When is the control time for rice stem borers?
The stem borer, also known as the yellow stem borer and the striped stem borer, is an important rice pest in coastal and riverside plain areas, severely affecting rice yield.So when is the control time for rice stem borers? How to control them?
When is the control time for rice stem borers?
Pesticides are generally applied during the peak emergence period of adult rice stem borers and the larval hatching period, that is, the effect is relatively good when the pesticide is used before they enter the rice plant. Among them, the control time for the striped stem borer and the yellow stem borer also requires attention:
(1) The striped stem borer mostly occurs at a distance of 1m from the ridge of the rice field. Observe the stem at a position about 10cm above the water surface. The leaf sheath shows irregular yellowing, and in severe cases is accompanied by brown stripes. At this time, if you pull open the leaf sheath, you will find striped stem borer larvae inside. This is the best period for control.
(2) The best control time for the yellow stem borer must be determined by both pest conditions and seedling conditions. When controlling dead-heart seedlings, pest conditions are the main factor, that is, pesticide application during the peak hatching period of egg masses. The second day after the bottom of 50% of egg masses turns black is the peak hatching period, and is the best period for controlling dead-heart seedlings. When controlling white heads, seedling conditions should be the main factor, that is, within the suitable control period, observe the rice growth stage; reaching the booting and heading stage is the best period for controlling white heads.
How to control rice stem borers?
1. Agricultural control
First, plow and turn the soil to reduce pest sources. Second, adjust the sowing period so that the 3 to 5 true-leaf stage of vegetable seedlings is staggered from the peak occurrence period of the cabbage webworm; third, irrigate appropriately to increase field humidity.
2. Chemical control
Spraying for control must seize the peak emergence period of adults and the larval hatching period. You can choose 1.8% Aifuding emulsifiable concentrate at 2500 to 3000 times dilution, Bt wettable powder at 800 times dilution, which should be applied early or chosen, or 21% Mieshabi emulsifiable concentrate at 2000 times dilution, 20% Jusha or 10% Juma emulsifiable concentrate at 1000 times dilution, or 2.5% Kung Fu emulsifiable concentrate at 3000 times dilution, or 10% Duolaibao suspension concentrate at 2000 times dilution, or 20% fenvalerate emulsifiable concentrate at 3000 times dilution, or 5% Laifuling emulsifiable concentrate at 3000 times dilution, or 10% Tianwangxing emulsifiable concentrate at 3000 times dilution, or 5.7% Baishude emulsifiable concentrate at 2500 times dilution, or 2.5% Decis emulsifiable concentrate at 3000 times dilution, or chlorbenzuron No. 3 suspension concentrate 100.
The rice stem borer is the most common and most harmful rice pest, so growers must do a good job of prevention and control in advance.