Occurrence And Control Of Main Pests And Diseases In Cotton Fields In Xiantao In August

First,

The four generation of the blind bug: the occurrence degree is 4 grade (moderately biased), and the local 5 level.

The peak period of nymphs was from August 15th to 30.

Spodoptera litura: the occurrence degree is 4 grade (moderately biased occurrence), a few plots 5 level (big happen), the young larvae are in the middle and late 8 months.

The four generation

The occurrence of red spider and aphid is 3 grade (moderate occurrence).

Two, the main basis

1. Insect pest in the field

Blind bug: due to the rainy days and heavy rainfall in the middle and late 7 months, the field control is inconvenient, and the third generation of bug bugs is very high in the field.

Systematic monitoring showed that on the peak day (July 25th), the average number of hundred insect pests was 42, of which 9 were adults, 33 nymphs, 9 more than that of last year's peak day. In the field survey, the average number of insect pests in the field was 0 to 32, and the number of pests in the field was 100.

Spodoptera litura: no insect has been found in the field.

Helicoverpa armigera: as monitored by the system, by the end of July 30th, the average number of eggs accumulated by the third generation of Helicoverpa armigera was 5.3, with an average of 2 insects per 100 plants, 15.3 and 2 less than last year.

In the field survey, the average number of insect pests per plant was 0.33.

Red spider and aphid: recent survey showed that the rate of spider mites was 0 ~ 60% in average, 12% on average, and 0 to 352 in three hundred plants, with an average of 201.

The aphid has an average aphid rate of 18% and an average of 706 aphids.

2.

The growth period of cotton is later than that of the whole year, and it is still bud flower boll stage in August.

The layout of crops in our city is complex and diverse. Cotton and maize, soybean, vegetable and other flower fields and flower arranging fields are abundant. The source of food is abundant, which is beneficial to the occurrence of the bug, Spodoptera litura and Helicoverpa armigera.

3. Climatic conditions

The weather forecast shows that the precipitation is relatively low in August.

Climatic conditions are favorable for occurrence of Spodoptera litura and Helicoverpa armigera.

Three, prevention and control advice

Blind bug: it is recommended that 1% methamidofin Benzoate Microemulsion, or 3% acetamiprid microemulsion, or 26% chlorofluorocarbon acetamiprid water dispersible granule, or 45% malathion emulsifiable concentrate, or 40% phoxim EC, etc. 1000 to 1500 times liquid spray.

Spodoptera litura and Helicoverpa armigera: it is recommended that 50% bromopropoxide EC (klong) and 1500 times liquid, or 48% chlorpyrifos EC (such as chlorpyrifos EC) (1500), or methylene salt (1% TM, 3% TM, etc.) 1500 to 3000 times liquid should be applied to spray the middle and upper part of the cotton plant evenly.

Red spider: it is recommended to use 3% avermectin (TM, etc.) wettable powder 3000 times liquid spray, or 10.5% Avi Ling wettable powder 1500 times liquid spray.

Aphids: it is recommended to use 25% imidacloprid 2000 times liquid or 3% acetamiprid 1000 times liquid spray.