Fall armyworm may invade Taiwan, China with southwest airflow; how to control it after a typhoon?
Originally distributed in the tropical and subtropical regions of the Americas, fall armyworm spread rapidly to Asia within 2 years. In the 107th year of the Republic of China, it reached Yemen, India, Bangladesh, Myanmar, Thailand, and Sri Lanka, and this year it advanced to mainland China, with outbreaks reported in 11 provinces. Fall armyworm mainly damages plants in the grass family, and its host range is very broad, including 76 families and 353 species. Its main targets are corn, rice, and sorghum, and its method of movement is astonishing: it can migrate with cyclones, with a direct-flight record in Africa of 100 km in one night, and a flight record of 250 km riding air currents in the Americas. The Council of Agriculture stated that although fall armyworm has not yet harmed Taiwan, China, it must not be left unguarded. The Bureau of Animal and Plant Health Inspection and Quarantine has released photos of fall armyworm and provided identification features. Once it is found, report it immediately.
Feng Haidong, Director-General of the Bureau of Animal and Plant Health Inspection and Quarantine of the Council of Agriculture, said that on the head capsule of mature fall armyworm larvae there is a yellow inverted-Y-shaped marking, and on each body segment of the larval back there are 4 spots arranged in a ladder-like distribution. The relevant features for identifying fall armyworm have been made into leaflets and distributed to farmers and industry operators. Once it is found in field areas, call the disease prevention hotline 0800039131 as soon as possible, and the Bureau of Animal and Plant Health Inspection and Quarantine will immediately adopt response measures.
3,800 hectares of sorghum and wheat in Kinmen require the greatest caution
The main host plants harmed by fall armyworm include economic crops such as corn, rice and sorghum, cotton, cruciferous plants, cucurbits, and solanaceous plants. Looking at the geographical distance, the Kinmen and Matsu areas bear the brunt. Jiang Mingyao, assistant researcher at the Taiwan Agricultural Research Institute of the Council of Agriculture, said they are more worried about Kinmen, because Kinmen is closest to mainland China, only 10 km away, and this distance is not a problem at all for the movement of fall armyworm. Kinmen has as much as 3,800 hectares planted with sorghum and wheat, and sorghum and wheat are precisely the main host plants of fall armyworm.
Based on foreign literature, assessing the possible pathways and risks of fall armyworm invading our country, if female adult fall armyworms invade the Kinmen area by flying and lay eggs to cause damage, each egg mass has about 100-200 eggs, and it is extremely easy for them to establish and reproduce in Kinmen.
As for the main island of Taiwan, China, the grass-family crop presumed to be harmed is sweet corn. There is no need to worry too much about rice. Jiang Mingyao said that because rice is flooded at different stages of cultivation, and if the soil is flooded, it is a great obstacle to the reproduction of fall armyworm, so it is estimated that it will not cause too much of a problem for rice.
Typhoons drawing in southwest airflow may bring fall armyworm The earlier it is detected, the better the control effect
When will fall armyworm fly to Taiwan, China? The tobacco cutworm belongs to the same genus Spodoptera as fall armyworm. Jiang Mingyao, an expert who studies the tobacco cutworm, said that it is not impossible for fall armyworm to fly directly to Taiwan, China. The Bureau of Animal and Plant Health Inspection and Quarantine believes that the coming typhoon season carries fairly high risk. According to migration records of fall armyworm in Africa and the Americas, it can fly 100 or 250 km in one night, and the distance between the main island of Taiwan, China and the mainland is only just over 100 km, which is not an impossible distance, especially when air currents are available. Feng Haidong believes that the southwest airflow drawn in after a typhoon may be the easiest way for fall armyworm to reach Taiwan, China, so the southwest airflow drawn in after a typhoon is a time point of very high risk for fall armyworm invasion.
As long as it is detected early, fall armyworm is actually not frightening. Even organic agriculture has materials that can be used for control. The Bureau of Animal and Plant Health Inspection and Quarantine has already reviewed the insecticides approved for use in the country. Any registered pesticide for the noctuid family can be used, and organic farmers do not need to worry either: Bacillus thuringiensis and neem oil can both control fall armyworm.
