Cabbage moth (cabbage moth) is also known as Brassica arborescens, Brassica napus, Latin name: Mamestra brassicae Linnaeus is Lepidoptera, Noctuidae. The Brassica julibrissalis has extremely high dietary habits. It is known that there are more than 100 species of 45 families in the host. The main vegetables are cabbage, broccoli, cabbage, radish, rape, eggplant, beans, melons, and potatoes. Kaoliang Wine,Chinese Famous Liquor,Buy Chinese Liquor Online,Buy Chinese Liquor Online Shan Dong Kao Shang wine industry Co.,Ltd , https://www.ksbaijiu.com
Hazardous features: Newly hatched larvae gather on the back of leaves, eat leafy leaves, and remain on the epidermis. 2 to 3 years of age scattered harm, eat leaves into holes, after 4 years of age, out of binge at night, leaving only the veins, petioles, old larvae can eat crops, and the migration of neighboring fields infestation. Older larvae have habits of drilling, often drill the ball or cabbage heart, excrete feces, and can induce decay caused by soft rot, so that vegetables lose their value.
Morphological characteristics Adults are 18-25 mm in length and 45-50 mm in wings. Gray-brown, grayish-black ring pattern on the front wing, grey kidney pattern, 3 small white dots on the proximal edge of the leading edge, sub-margin line is white and fine, there is a black dot along the outer edge, the hind wings are gray, and no markings .
?? egg hemispheres, bottom diameter of 0.6 ~ 0.7 mm, the surface with a radial three-sequence longitudinal ribs, with a cross between the ridges, the initial production of yellow-white, black purple before hatching.
The last larvae of larvae have a body length of 29.1 mm. The newly hatched larvae are blackish green, and their body color varies from light green to dark brown. Somber obvious. The topline and subline are white dots, the valve lines and valve lines are grayish white, and there are black streaks on both sides of the body back. The first and second instar larvae lacked the first two pairs of gastropods and walked like a ruler.
About 20 mm in length, reddish-brown or dark brown, with a dark vertical band at the center of the back, with a long hip thorn, with 2 long thorns and a bulbous spine.
Living habits: Brassica oleracea occurs in Tibet in 1 generation, in Gansu (Jiuquan) in 1-2 generations, in the Northeast, in the northwest in the 2nd generation, in Liaoning (Xingcheng), in North China, in Central China, in the East in 2-3 generations, in Sichuan (Chongqing) and in Hunan. , Shaanxi (Wu Hui) 3-4 generations, all over the diapause in the soil in winter. The overwintering mites are mostly under the host plants Honda, Tanabe weeds or field terriers. In the spring of the second year of spring from March to June, when the temperature rises to 15 to 16°C, the adult feather emerges unearthed, more irregular, and the emergence period is longer. Adults live in a nocturnal manner, with activity peaking in the middle of the night. Adults have chemotaxis, strong tendencies toward molasses, and poor phototaxis. Females have greater phototaxis than male moths, and females have one mating for a lifetime. Eggs are produced in lush foliage. Dark green plants. Monolayers of eggs are located in the middle and lower leaves, each with 60 to 150 capsules. General female moths live for 5-10 days, lay 500-1000 eggs, and spawn up to 3000 eggs. The egg development temperature is 23.5 to 26.5 degrees Celsius, and the duration is 4 to 5 days. After the 3rd instar, the leaves are scattered and damaged. The leaves form a hole. After 4th instar, they are hidden in the back of the leaves during the day, or in the surface soil near the root of the host, and come out at night for feeding. , but when the plant density is high, it is not hidden during the day. After 3rd age, the cabbage and cabbage leaves were damaged. After 4 years of age, the food intake increased, with the highest food intake at 6 years of age, which accounted for 80% of the total food intake. The damage was most intense. The larval development optimum temperature 20 ~ 24.5 degrees Celsius, duration of 20 to 30 days. After the larvae matured, they sneaked into the topsoil of 6-10 cm for the purpose of soil lice. The pupa period was generally 10 days. The pupa period was about 2 months. The overwintering pods could reach more than half a year. Brassica julibrissioides prefers a warm and humid climate with an average daily temperature of 18-25 degrees Celsius and a relative humidity of 70%-80% for favorable growth, temperatures below 15 degrees Celsius or above 30 degrees Celsius, and humidity below 65% or above. 85% is unfavorable. Brassica zea is an intermittent, locally occurring pest that often occurs in spring and autumn within one year.
The natural parasitoids of Brassica oleracea have natural parasitoids such as Trichogramma, Trichogramma, etc.; the larval stage parasitoids include Brassica napus, Spodoptera littoralis, Spodoptera litura, etc. In the flood season, there are a large number of leg wasps and so on. Predatory natural enemies such as armor, tiger, ant, wasp, and spider also play a role in larval stage. According to the investigation in Chongqing, foot worms and single worms are one of the main factors that inhibit second-generation larvae.
Control methods
1. After the agricultural crops are harvested, they can be ploughed in autumn or winter till deeper. Eradication of weeds can eradicate some of the overwintering mites. In combination with agricultural operations, the leaves gathered by the egg masses and the instar larvae are promptly removed and concentrated.
2, trapping and killing adults to use adult phototaxis and chemotaxis, in the eclosion period set black light or sweet and sour basin (tractor of sugar, vinegar, wine, water ratio of 10:1:1:8 or 6:3:1: 10).
3, biological control First, the larvae before the 3rd instar application of bacterial insecticide Bacillus thuringiensis: Bt suspension agent, Bt wettable powder, generally containing 10 billion spores per gram, 500 to 1000 times the water spray, select the temperature above 20 degrees Celsius sunny Spray effect is better. The second is the artificial release of Trichogramma during the egg period, set 6-8 points per 667 square meters, each time each point put 2000 to 3000 heads, once every 5 days, continuous 2 or 3 times.
4. Control of chemical agents We must control chemical pesticides at the favorable timing when the 3rd instar larvae are concentrated, food intake is weak, and drug resistance is weak. Commonly used agents and dosages refer to cabbage butterfly. The type of medicine used is also selected to be 2000 times and 2500-3000 times the number of hits. If one or two of the larvae is missed, the 2000 times spray of Mizuki can be used. To prevent the emergence of drug resistance, pesticides should be used alternately, without the use of multiple pesticides or continuous use of single pesticides. The amount of water must be sufficient when the drug is used, and the spray should be applied evenly.