Occurrence and Control of Spodoptera litura and Spodoptera exigua in Shanghai

Spodoptera litura: The annual probability of severe occurrence is 70%, and the annual probability of moderate occurrence is 30%.

Spodoptera exigua: The annual probability of moderate occurrence is 80%, and the annual probability of recurrence is 20%.

Second, the prediction basis

The Municipal Agricultural Technology Extension Service Center held a dynamic monitoring and communication exchange between Spodoptera litura and Spodoptera exigua on June 30. The plant protection staff and the surveyors of the nine counties and the Guangming Group exchanged the data of the current monitoring data of the two larvae. The summary is as follows:

Spodoptera litura

Investigation of the moth system under the black light in the monitoring station of the Vegetable Technology Service Center in Minhang District. The adults were observed on May 3, 20 days earlier than May 23, 2007 and six days later than April 27, 2006, compared with the five-year average. May 9 as early as 9 days. By the end of June 26, the accumulated amount of moths was 29. In the same period of 2007, there were 12 in the same period of 2006, 11 in the same period of 2006, 26 in the same period in 2005, and an average of 15.6 in the same period of the same period in the five years; sexually induced adults began to see June 26 from the beginning. The number of accumulated moths was 1,152, which was 1,414 in the same period of 2007 and 576 in the same period of 2006. The main moth peak period from June 22-26, accumulated 297 heads of moths on four days. The Chongming County Vegetable Technology Promotion Station measured the number of accumulated moths at the end of June 25 and ended June 25. The accumulated number of moths was 598, and the cumulative number of moths in Zhongxing Town, Chongming County from June 20 to June 26 was 1481. . A total of 1031 cumulative moths were detected in Pudong New Area, and 736 accumulated in Jinshan District.

2. Spodoptera exigua

Investigation of the moth system under the black light in the monitoring station of the Technical Service Center of Minhang District. Adults started on May 7th, 6 days earlier than May 13, 2007, and 31 days later than April 6, 2006, compared to the 5-year average. From May 3 to May 25, the cumulative moth volume was 738, compared with 30 in the same period of 2007. In the same period of 2006, it was 79 in the same period and 49 in the same period in 2005, which was 21.3 times that of the average of 34.7 in the same period of five years; The total number of moths accumulated since the beginning of June 25 was only 240, compared with 23 in the same period of 2007, 19 in the same period of 2006, and 633 in the same period of 2005. According to the investigation of the moth trap system under the black light lamp at the monitoring station of the Chongming County Vegetable Technology Promotion Station, the total number of moths attracted was 1,336 from the first day of observation until June 25, and 727 sexually induced adults, of which the main moth peak was from May 30 to May 6. On the 12th and 13th days of the month, the cumulative amount of moths was 1063, which accounted for 79.5% of the total number of moths.

3. Daejeon Infestation Survey: Most districts and counties and Guangming Group investigated the damage of two species of tobacco moths on cowpea, edamame, leeks, leeks and other crops. Minhang, Chongming County, Jinshan District, Songjiang District, etc. were in the field. Larvae have been found.

Third, the trend analysis

Since May this year, the temperature is high, and the hot and humid showers are conducive to the early migration of two adult moths, and they can reproduce in the local area. Since the beginning of June, the weather is still hot and heavy, and it is extremely suitable for two kinds of moths. Occurrence and base reproduction, recent rains in southern areas such as Guangdong, Guangxi, and Fujian have caused floods in larger areas, resulting in high local residual insect populations and abundant exodes; exogenous moth peaks converge with local breeding insects to form In the near future, there are many moths and more frequent peaks of moths. It is expected to enter the beginning of the second generation from the beginning of July, 10-15 days earlier than the normal year. According to comparative analysis of the amount of moths during the same period of the previous years from 1992 to 2007, Spodoptera litura is expected this year. In line with the recurring trend, Spodoptera exigua has a tendency to re-emerge. It is hoped that the districts and counties will pay attention to the occurrence of Spodoptera litura and organize timely prevention and treatment.

Fourth, prevention advice

1, control period

According to the characteristics of the duration of two species of insects, the occurrence period of the insects, and the characteristics of this year's tendency to become heavy, it is recommended that the second generation should be organized for secondary prevention. The first control period is July 5-8. , the second time in July 12-15; the first period of the third generation of the control period is appropriate by the end of July, the second August 8-10; the first control period of the fourth generation period 8 On the 25th to the 28th of the month, the second on September 5-8; the fifth generation of the prevention and control of the second generation, the appropriate period in the early October - 5, the second October 12-15.

2, prevention techniques

According to the habit of nocturnal moth larvae nocturnal, medication time should be carried out in the evening, it is best to control after 6 o'clock.

3, pharmaceutical control

Optional tamper (150 g/litre indoxacarb suspension) 3000 times, dilute (10% chlorfenuron suspension) 2000 times, the United States in addition (50 g/litre urea urea emulsifiable concentrate) 1000 times, San Ling (2.2 2500-fold microdilution agent for Acarbose, 2000-fold for Retong (24% Methoxyfenozide Suspension), and Ao-Green No. 1 (1 billion PIB/mL for Autographa californica Nuclear Polyhedrosis Virus Suspension) 1000 Times, card dead grams (5% flufenoxil EC) 1000 times spray control. It is necessary to publicize the characteristics of vegetables to subsidize pesticides, and pay attention to the rational use of pesticides, delay the development of insecticide resistance to pesticides, and pay attention to the safety of various pesticides harvest interval, reduce pesticide residues.

Author: City Agricultural Center Plant Protection Division