In accordance with the requirements of the”Regulations on the Prevention and Control of Crop Diseases and Insect Pests”, in 2020, the National Agricultural Technology Center will organize 100 national pesticide resistance monitoring points for rice planthoppers, rice stem borers, and wheat The resistance of 24 major diseases, insects and weeds, including aphids, wheat head blight, whitefly, rice (wheat) field weeds, etc., was monitored. After consultation with experts, the”National Agricultural Pest Resistance Monitoring Report in 2020″ was formed. This article only extracts the relevant content of”the resistance status of vegetable pests”.
The diamondback moth populations currently monitored in vegetable production areas in North China and the Yangtze River Delta are sensitive to low-level resistance to the bisamide chlorantraniliprole (resistance factor 2.4 ～5.7 times), the resistance to indoxacarb is at a moderate level (resistance multiples of 11 to 56 times), and it is at a low to moderate level of resistance to chlorfenapyr (resistance multiples of 6.7 to 18 times). Compared with the monitoring results in 2019, the overall resistance of Plutella xylostella to the above agents has not changed much.
two countermeasures and suggestions
Plutella xylostella is one of the most severely resistant vegetable pests. It has developed resistance to various pesticides to varying degrees, and its prevention and control Comprehensive resistance management measures should be adopted. According to the forecast results, it is emphasized that pesticides should be applied during the young larval stage, abamectin and beta-cypermethrin should be stopped, and chlorantraniliprole, tarfenac, indoxacarb, spinetoram and other agents should be strictly controlled in the diamondback moth. The frequency of use in prevention and control, the use of vegetables in each season should not exceed once. Pay attention to alternate and rotating use of different action mechanisms of agents or combinations of agents to control Plutella xylostella and delay the development of resistance.
At present, the beet armyworm populations in the monitored area are at a high level of resistance to the bisamide agent chlorantraniliprole (the resistance factor is greater than 600 times), among which Baiyun, Guangdong The population resistance factor is the highest, reaching 4185 times; the resistance to indoxacarb is at a medium to high level (the resistance factor is 70-220 times), and the Shanghai Chongming, Hubei Huangpi, and Guangdong Baiyun populations are all at a high level of resistance (the resistance factor is 105～220 times); low to moderate resistance to insect growth regulator methoxenozide (7.2～59 times of resistance); sensitive to low resistance to spinosad (resistance) Multiples of 4.1 to 6.8 times). Compared with the monitoring results in 2019, the resistance of beet armyworm to chlorantraniliprole and indoxacarb has increased by 2 to 4 times.
Beet armyworm is one of the most resistant vegetable pests, and comprehensive resistance management measures should be adopted for its prevention and control. According to the forecast results, it is emphasized that the application of pesticides in the young larval stage is emphasized, the use of chlorantraniliprole and indoxacarb is suspended, and the use of methoxenic hydrazide and spinosad in the control of beet armyworm is strictly controlled. , Vegetables should be used no more than once per season. Pay attention to alternate and rotating use of agents with different mechanisms of action or combinations of agents to control beet armyworm and delay the development of resistance.
At present, the nymphs of Bemisia tabaci in the monitoring area are at a moderate to high level of resistance to cyantraniliprole and spirotetramat (resistance to cyantraniliprole 17～ 768 times, 82～1651 times to spirotetramat), among which the populations of Wuhan, Hubei and Changsha, Hunan are at a high level of resistance, and the resistance is greater than 200 times; the adults of Bemisia tabaci are at low to moderate levels to thiamethoxam Horizontal resistance (resistance multiples of 5.4 to 12 times). Compared with the monitoring results in 2019, the overall resistance of Bemisia tabaci to the above-mentioned agents has not changed much.
In view of the high resistance of Bemisia tabaci populations in the vegetable production areas of Hubei and Hunan, pay attention to alternating and rotating the use of fluroxypyr, sulfoxaflor, and nitridine Different mechanisms of action or combination of insecticides such as insecticide and dinotefuran control whitefly and delay the development of resistance.
Western Flower Thrips
The populations of Western flower thrips in the monitoring area have high levels of resistance to spinetoram and emamectin benzoate (to ethyl Spinosyn resistance multiples of 195 to 10095 times, p-ethylamino abamectin benzoate resistance multiples of 331 to 1384 times); moderate to high levels of resistance to spinosad and tarfenil The resistance to thiamethoxam is 34 to 2552 times, the resistance to tarfenile is 24 to 295 times), and the resistance to thiamethoxam is at a low to medium level (the resistance is 5.5 to 37 times). Compared with the monitoring results in 2019, the overall resistance of Western Flower Thrips to the above drugs has not changed much.
In areas where the western flower thrips is highly resistant to insecticides, the use of spinetoram and emamectin benzoate should be suspended , Pay attention to alternate and rotating use of insecticides with different mechanisms of action such as carfenil, thiamethoxam or combinations of agents to control Western flower thrips, and delay the development of resistance.
At present, the population of Tetranychus urticae in the monitoring area is highly resistant to abamectin (resistance factor 304～1051 times); the resistance to carboclofen is moderate The highest level of resistance (36 to 113 times of resistance), among which the Yinchuan population is at a high level of resistance, with a resistance of 113 times; and it is at a medium level of resistance to pyraclostrobin (the resistance is 23 to 57 times). Para-bifenazate is in a sensitive state. Compared with the monitoring results in 2019, the overall resistance of Tetranychus urticae to the above agents has not changed much.
In the Tetranychus urticae prevention and control strategy, the use of abamectin should be suspended, and attention should be paid to alternating and rotating the use of tebufenil, bifenazid, and pyriprazine Different action mechanism agents such as dicofenate and etoxazole or a combination of agents control Tetranychus urticae and delay the development of drug resistance.