On the forum, I saw that a farmer friend Long Shichang asked what diseases and pests the tomatoes had? The blade was horrible!
Photo by farmer Long Shichang
It is the harm of spotted fly diving, adult insects wrap their eggs in the leaf flesh, the larvae begin to eat the leaf flesh after birth, and see the curved "white moth road" is the result of the larvae encroaching on the leaves, commonly known as "ghost painting symbols". Severe latent scars are dense, destroying the normal organization of leaves, affecting the photosynthesis of plants, causing leaf shedding, premature plant aging, and adverse effects on crop production and vegetable planting. The damage in the picture is already very serious, and most of the leaf tissue is damaged. The control is a little late, and you can use potions such as Benevir that are good for dead insects.
<h1>Occurrence characteristics</h1>
Spotted diving flies occur in the southern provinces generally 21-24 generations per year, no overwintering phenomenon, adult worms stab the leaves with ovipositors, suck sap, females lay eggs under the epidermis of some wound holes, eggs hatch after 2-5 days, larval stage 4-7 days, the last larvae bite through the leaf epidermis pupae outside the leaf or under the soil surface, pupae feathered into adults after 7-14 days, 2-4 weeks in summer and 6-8 weeks in winter per generation.
Spotted fly adults and larvae
Adult insects have phototropism, greening, yellowing, a day, 12 noon the most number, 2-4 pm the most vigorous activity, sunset stops, rainy days adult insects less, rainy began to appear in large numbers.
Spotted diving flies have the characteristics of strong reproductive ability, wide range of hosts, large number of generations, and serious generation overlap, which can occur all year round, and spotted diving flies have always been a relatively serious pest in vegetables.
<h1>Integrated prevention and control measures</h1>
1. Agricultural measures
After the harvest of the former stubble crop, the weeds, old leaves, diseased leaves and residual leaves are removed in time, and buried or burned in a concentrated manner to eliminate the source of insects. During the peak of pest occurrence, the leaves with insects are removed in time and incinerated.
2. Physical prevention and control
Booby-trapping of armyworm plates: Adults of spotted flying flies are yellowing, and yellow plates can be hung in the field, generally hanging 20-30 cm on the top of the plant.
Insecticidal lamp booby-trap: Leafminer adults also have phototropism, can use insecticidal lamps for booby-trapping, the effect is also ideal.
3. Biological control
As a natural enemy of spotted fly larvae, parasitic wasps can reach more than 50% without medication. Parasitic wasps with better parasitic rates include Chick bees and submarine cocoon bees. This method is more suitable for organic green cultivation.
Insect growth regulators are used to influence adult reproduction, egg hatching, and molting and pupal of larvae.
4. Greenhouse smokehouse
It can be fumigated with sulfur powder before colonization. In the growth period of leafminer fly common occurrence can be selected for dichlorvos emulsion treatment, both periods of smoking shed can effectively reduce the insect population base, reduce the harm.
5. Pharmaceutical prevention and treatment
When the larvae are 1-2 years old, it is the most critical period for the moth, and the worm passage at this time is about 1-3 cm. Optional containing avermectin, high-efficiency cypermethrin, fly amine, methyl vitamin salt and other agents, when spraying, remember to be comprehensive and thoughtful, the front of the leaf and the back of the leaf must be taken into account. Pay attention to the alternating use of pesticides, to continuous prevention and control, generally sprayed once every 7-10 days.
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