65% methiocarb·diethofencarb wettable powder, registered for cucumber gray mold, 80-125 g/mu, spray.
The design philosophy behind this formulation is very clear, and the product performance section states it very directly:
This product is a compounded formulation of thiophanate-methyl and diethofencarb, and is a systemic fungicide.Inhibit the formation of the spindle apparatus in Botrytis cinerea spores., for the control of cucumber gray mold.
The key target is the "spindle apparatus" — a target for disrupting cell division in Botrytis cinerea.
Gray mold (caused by Botrytis cinerea) is widely recognizedResistance evolves most rapidly.one of the diseases. There are three reasons:
Short generation.Under suitable conditions, Botrytis cinerea can complete one generation within a few days, and can undergo more than a dozen generations or even more in a year.
High spore production.A single lesion can produce tens of thousands of conidia, resulting in an enormous population base.
Prone to mutation.Massive reproduction + short generation = high probability of variation.
The result is that a single agent often becomes significantly ineffective after only two to three years of use. This is why specialized formulation design is required for the control of gray mold.
Diethofencarb belongs to the diethylimide class.Its most critical feature is:It remains active against Botrytis cinerea strains that have developed resistance to benzimidazoles.
This means:
Methyl thiophanate (converted to carbendazim in vivo) is effective againstSensitive strains
- Diethofencarb againstResistant strains
The two components have different sites of action, formingBidirectional compressionIn field populations of Botrytis cinerea, both sensitive and resistant strains coexist, and this combination can cover both types simultaneously.
SymptomsWater-soaked lesions appear on petals, young fruit, and leaves, with a gray mold layer (conidia) developing on the surface. Affected fruit subsequently rots.
Occurrence conditions请提供需要翻译的中文段落。
Low temperature and high humidity (15–25°C, relative humidity above 90%)
Insufficient light
Poor ventilation
Protected cultivation cucumbers are a high-incidence scenario.High humidity, poor ventilation, and day-night temperature differences within the greenhouse lead to prolonged leaf surface condensation.
Portals of infection请提供需要翻译的中文段落。
I'm sorry, but you haven't provided the Chinese paragraph to translate. Please send the Chinese text you'd like me to translate into professional English.FlowersPetals serve as a high-quality nutrient substrate for Botrytis cinerea; after petal fall, the residual petals adhering to young fruit provide a site for the pathogen to establish infection.
It appears that only "2." was provided, with no Chinese paragraph to translate. Please send the Chinese text you'd like translated into English.Wound— Wounds from fruit harvesting and pruning serve as infection entry points.
3.Senescent tissue— Old leaves and diseased leaves
The fruits, leaf surfaces, and undersides of the leaves of cucumber plants should all be sprayed.— The registration specifically mentions fruit.
This is because cucumber gray mold mainly damages young fruits, and the disease is most likely to occur where flower petals remain. When spraying, it is essential to:
- Apply to young fruit (especially where withered flowers remain attached)
Spray onto the underside of the leaves.
Apply to the lower older leaves of the plant.
"Once every 10 days"— slightly shorter than the 10–15 days of carbendazim, as gray mold develops rapidly under high-humidity conditions in the greenhouse.
This point must be emphasized:Gray mold is a typical environment-related disease.Chemical agents alone can hardly achieve complete control of recurrent disease outbreaks in high-humidity environments.
Supporting measures:
Ventilate and reduce humidity after pesticide application.
Control irrigation (avoid flood irrigation; switch to drip irrigation or subsurface irrigation under plastic film).
Promptly remove diseased fruits, diseased leaves, and spent flowers, and carry them outside the greenhouse for disposal (do not discard them inside the greenhouse).
Rational close planting to improve ventilation and light penetration.
The value of removing diseased and senescent plant material often exceeds that of applying an additional round of pesticide.— It directly reduces the base level of inoculum.
Although this mixture is designed for resistance management,Resistance to diethofencarb has also been reported.Therefore:
This mixture should not be used alone on a long-term basis.Number of control applications within the season, rotation with agents of different modes of action:
- Strobilurin fungicides (pyraclostrobin, azoxystrobin) — note that this class inherently carries a high risk of resistance development.
- Anilinopyrimidines (pyrimethanil)
- Succinate dehydrogenase inhibitor (SDHI) fungicides (e.g., boscalid, fluxapyroxad)
- Microbial-origin formulations (Trichoderma spp., Bacillus subtilis)
Alternating multiple mechanisms of action is a necessary condition for the management of gray mold.
Do not mix with strongly alkaline pesticides or copper-containing formulations.
Secondary dilution for pesticide preparationFor wettable powders, first dissolve the powder to prepare a mother liquor.
The pre-harvest interval shall be implemented in accordance with the registered label.Continuous harvesting of cucumbers requires strict verification.
The pre-harvest interval for cucumber is 7 days, with a maximum of 3 applications per season.
Cucumbers are harvested continuously (picked every 2–3 days), so a 7-day interval means that after pesticide application during the peak fruiting stage, harvesting must be suspended for 7 days. Although this is not particularly long, it still requires planning.
Allocation of the 3-application upper limitApply once at first appearance of disease spots, once after consecutive cloudy days, and once when the disease recurs. After completing the regimen, rotate to products with different modes of action.
Do not apply during the flowering period of flowering plants.This point concerns bees — diethofencarb and thiophanate-methyl have effects on bees. Although cucumbers mainly rely on self-pollination, if bees are used for pollination in the greenhouse (many greenhouses introduce bumblebees), the application timing should avoid the pollination peak (usually in the morning).
Precautions: This product must not be mixed with copper-based formulations, strongly alkaline pesticides, or similar substances.After spraying copper, mercury, or alkaline pesticides, an interval of one week must be observed before applying this product.请提供需要翻译的中文段落内容。
"A one-week interval" is a specific figure that is easier to follow than the vague instruction "do not mix."
Why is such a long interval required?Residues of copper ions on leaf surfaces and equipment can persist for a period of time, and simple rinsing may not remove them completely. The effect of alkaline agents on leaf surface pH also requires time to recover.
Packaging materials shall be incinerated or buried deep, and must not be discarded at will.
Avoid contaminating water sources. Do not clean application equipment in rivers, ponds, or other water bodies.
Pregnant and lactating women must avoid contact.
It is recommended to rotate with fungicides having different modes of action to delay the development of resistance.
