Why are vegetable leaves covered with sores? Why do vegetable farmers work in the field for three days and at two ends? Why do so many seedlings die mysteriously? Behind many vicious incidents, it is because of a small insect at work! That's right, it's the number one pest of leafy vegetables, the yellow-striped jumping beetle.
Yellow Stripe Jumping Armor "A Life of Sin"
Close-up of jumping armor
Yellow striped jumping armor is also known as vegetable fleas, soil fleas, etc. in some places, and the common ones are yellow curved strip jumping armor, yellow straight jumping armor, yellow wide strip jumping armor and yellow narrow strip jumping armor. The hazard crops are widespread, especially cruciferous plants.
imago
Yellow stripe jumping armor hazards
Often clustered on the back of the leaves to feed, small, can fly, very lively, life expectancy of about 50 days, long can survive for 1 year.
Nibbling on the leaves often causes the damaged leaf surface to be covered with dense oval holes, so that the leaves wither, photosynthesis is reduced, and the value of the commodity is lost.
Jumping nails are tender and like to feed on the young parts of the leaves, so the seedling stage is the most seriously affected, often causing seedling destruction.
ovum
Jumping nail spawning site
Adult eggs are mostly laid in the soil crevices around the roots of the plant or on fine roots, the eggs are about 0.3 mm long, oval, pale yellow translucent, and the egg stage is 4 to 9 days.
larvae
Yellow-striped jumping beetle larvae
Yellow-striped beetle larvae have 3 instar stages, and the larval stage is about 11 to 16 days. The old mature larvae are about 4 mm long, cylindrical, yellowish-white, with inconspicuous sarcomas at each segment, and fine hairs.
Larvae are infested symptoms
The hatching larvae feed along the whisker root to the main root, peel off the epidermis of the root, forming an irregular stripe scar, and can also bite off the whisker root, so that the leaves of the plant are yellow and dead, and even cause decay to cause soft rot to spread.
chrysalis
Yellow-striped jumping chrysalis
Mature larvae mostly pupate in soil 3 to 7 cm deep. The pupa is about 2 mm long, oval, milky white, with a head hidden under the forebreast, wings and feet up to the 5th abdominal segment, and sparse brown bristles on the back of the thorax. At the end of the abdomen there is a pair of forked protrusions, and the fork end is brown. The pupal period is 11 to 13 days.
The difficulty of prevention and control of yellow stripe jumping nails
Outstanding athleticism
Jumping armor is named because of the expansion of the hind foot and leg joints and the very good at jumping. It is very sensitive to medicinal agents, and when people spray medicine, even a slight spray can be felt, and they will immediately jump to the ground or burrow into the soil to avoid, which has caused great obstacles to the prevention and control work.
High resistance
With the continuous cultivation of cruciferous vegetables and the excessive use of chemicals, the resistance of jumping nails has become stronger and stronger. In particular, the frequent use of the same agent for prevention and treatment will accelerate the development of drug resistance.
The insect population base is large
The number of generations of jumping nails in a year gradually increases from north to south, and more than 10 generations can occur in the southern region. And the adult worms have a very long lifespan, averaging 50 days, up to 1 year. Coupled with the prevalence of facility cultivation, it provides a rich food source for the wintering of jumping nails, and the insect population base is increasing year by year.
Suspended animation
Adults jump off the blades after being frightened, roll over and briefly suspend themselves after landing on the ground. After determining safety, you should eat and drink, which increases the difficulty of prevention and control.
It is difficult to take medicine
After the jumping nail mating in the soil to lay eggs, hatched larvae eat roots, adults eat leaves, which adds difficulty to the drug, usually growers in order to save labor or medication costs, either spray or drizzle roots, prevention and control work is difficult to complete.
Integrated prevention and control methods for jumping nails
1. Timely prevention and control of jumping nails
● In the season of higher temperatures, most of the adult insects dive back into the soil at noon, and it is generally difficult to kill by spraying. It can be sprayed at 7:00 to 8:00 in the morning or 5:00 to 6:00 in the afternoon, at this time, the adult insects are less active and have good efficacy after they emerge.
● In autumn and winter, jumping beetles are particularly active around 10:00 a.m. and 3:00 p.m. to 4:00 p.m., and are prone to panic and run around, but often lie still at the bottom of the leaves at noon. Therefore, it can be sprayed in the morning when the adults are just emerging, or at noon or in the afternoon when the adult activity is in a "fatigued" state.
2. First outside and then inside
Jumping beetles have a strong jumping nature, spraying from the inside to the outside, jumping beetles are easy to escape, so when spraying, you should pay attention to spraying from the edge of the field to the inside, in order to prevent adult insects with strong jumping ability from escaping.
● If the field is wide, it should be sprayed around first and surrounded by insecticide;
● The field is narrow and long, and can be sprayed at one end first, and then sprayed from the other end, so as to achieve "encirclement and interception" to prevent adult insects from escaping.
● The spraying action should be light and do not disturb the adult insects.
3. Prevention and treatment of both upper and lower levels
Jumping armor only considers spraying on the ground, which is often less effective. Jumping nails not only harm crop leaves, but also harm crop roots, and should be treated together.
● After the crop is harvested, the residual leaves are thoroughly collected, the weeds are uprooted and burned, and the soil is deeply turned before sowing to eliminate some of the insect pupae and worsen the overwintering environment of the insects, which can reduce the harm.
● In addition, lay mulching to prevent adults from laying eggs on the roots.
● In the heavily endangered area, before sowing or before colonization, the soil is treated by sprinkling poisonous soil or spraying liquid first, and the insect pupae in the soil are poisoned and killed.
4. Pay attention to alternate medication
There are many drugs that can prevent jumping beetles, but a single drug is prone to drug resistance, which affects the prevention and control effect.
● When the larvae are found to begin to harm the roots of vegetables, irrigate the roots with 90% crystalline dimethallus or 50% octathion emulsion 1000 to 1500 times liquid, 100 to 200 ml of irrigation solution per tree.
● When there is a hazard in the field, insecticides such as acetamidine, pyridoxine and permethrin can be sprayed, which can be mixed or alternately used, but not a single drug.
● In addition to pharmaceutical prevention and control, physical prevention and control can also be carried out by using the yellowing and phototropism of jumping nails. Such as yellow plate booby-trap, set up insect-proof nets, lamp traps insects, etc. and chemical control collection.
Article Source: Agricultural Assistant (id: nyzs360)