How should imidacloprid and acetamiprid be used correctly?

I. Acetamiprid

Acetamiprid is a novel, broad-spectrum insecticide with moderate acaricidal activity; it functions as a systemic insecticide when applied to soil or foliage. It is widely used for the control of aphids, leafhoppers, thrips, and certain lepidopteran pests in rice, as well as in vegetables, fruit trees, and tea crops.

Application method:

At concentrations of 50–100 mg/L, it can effectively control cotton aphids, vegetable aphids, peach fruit moths, and other pests. When applied at a concentration of 500 mg/L, it controls leaf miners, citrus leaf miners, and pear fruit moths, and also kills eggs.

Acetamiprid is primarily applied via foliar spray to control pests, with the specific dilution ratio or dosage varying according to the active‑ingredient concentration of the formulation. On fruit trees and tall‑statured crops, it is typically used as a 3% formulation at 1,500–2,000-fold dilution, a 5% formulation at 2,500–3,000-fold dilution, a 10% formulation at 5,000–6,000-fold dilution, or a 20% formulation at 10,000–12,000-fold dilution; alternatively, a 40% water‑dispersible granule can be applied at 20,000–25,000-fold dilution, a 50% water‑dispersible granule at 25,000–30,000-fold dilution, or a 70% water‑dispersible granule at 35,000–40,000-fold dilution, all by uniform spraying. On short‑statured crops such as cereals, cotton, oilseed plants, and vegetables, a formulation containing 1.5–2 g of active ingredient per 667 m² is generally applied, mixed with 30–60 L of water for spraying. Uniform and thorough application enhances the efficacy of the pesticide.

Main uses

1. Chloronicotinyl insecticides. This class of compounds is characterized by a broad spectrum of activity, high efficacy, low application rates, long residual activity, and rapid action. It exhibits both contact and stomach toxicity, as well as outstanding systemic properties. It is effective against pests belonging to the Hemiptera (aphids, leafhoppers, whiteflies, scale insects, and other armored scales), Lepidoptera (diamondback moth, leaf miners, codling moths, and stem borers), Coleoptera (longhorn beetles and weevils), and Thysanoptera (thrips). Moreover, because its mode of action differs from that of currently widely used insecticides, it demonstrates particular efficacy against pests resistant to organophosphates, carbamates, and pyrethroids.

2. Highly effective against pests of the Hemiptera and Lepidoptera orders.

3. Belonging to the same chemical class as imidacloprid, acetamiprid boasts a broader insecticidal spectrum and is particularly effective in controlling aphids on cucumbers, apples, citrus fruits, and tobacco. Due to its unique mode of action, it also demonstrates strong efficacy against pest populations that have developed resistance to organophosphates, carbamates, and pyrethroids.

II. Imidacloprid

Basic Introduction

Imidacloprid is a highly effective neonicotinoid insecticide characterized by broad spectrum activity, high efficacy, low toxicity, and minimal residue. It exhibits low risk to humans, livestock, plants, and beneficial organisms, and exerts multiple modes of action, including contact, stomach poisoning, and systemic uptake. Upon contact with the pesticide, it disrupts normal neural transmission in pests, leading to paralysis and death. The product demonstrates rapid knockdown, with significant control achieved within one day of application, and a residual period of approximately 25 days. Its efficacy is positively correlated with temperature—higher temperatures enhance its insecticidal performance. It is primarily used for the control of piercing‑sucking pests.

Characteristics of Action

Imidacloprid is a systemic nitro‑methylene insecticide that acts as an agonist at the nicotinic acetylcholine receptor, disrupting the pest’s nervous system and impairing chemical signal transmission, with no cross‑resistance issues. It is used to control sucking‑mouthpart pests and their resistant strains. As a next‑generation chloronicotinyl insecticide, imidacloprid offers broad spectrum activity, high efficacy, low toxicity, and minimal residue; it is unlikely to induce resistance in target pests and is safe for humans, livestock, crops, and beneficial organisms. It exhibits contact, stomach‑poison, and systemic modes of action. Upon exposure, the pesticide blocks normal neural transmission, leading to paralysis and death. It provides rapid knockdown, with significant control achieved within one day, and maintains residual activity for approximately 25 days. Its efficacy is positively correlated with temperature—higher temperatures enhance its insecticidal performance. It is primarily employed for the management of sucking‑mouthpart pests.

Instructions for Use

It is primarily used to control piercing‑sucking pests (and can be alternated with acetamiprid at low and high temperatures—use imidacloprid in cooler conditions and acetamiprid in warmer ones), including aphids, leafhoppers, whiteflies, leafhoppers, and thrips. It is also effective against certain beetles, flies, and moths, such as rice weevils, rice water weevils, and leaf miners. However, it is ineffective against nematodes and red spider mites. It can be applied to crops including rice, wheat, corn, cotton, potatoes, vegetables, sugar beets, and fruit trees. Owing to its excellent systemic activity, it is particularly well suited for seed treatment and granular application. Typically, 3–10 grams of the active ingredient per mu are diluted in water for foliar spray or mixed with seeds. The pre‑harvest interval is 20 days. When applying, take appropriate protective measures to avoid skin contact and inhalation of dust or spray; wash any exposed areas thoroughly with clean water after use. Do not mix with alkaline pesticides. Avoid spraying under strong sunlight to prevent reduced efficacy.

To control pests such as the rose aphid, apple woolly aphid, peach aphid, pear psylla, leafroller moths, whiteflies, and leafminers, apply a 10% imidacloprid solution diluted 4,000–6,000 times by spraying, or use a 5% imidacloprid emulsifiable concentrate diluted 2,000–3,000 times. For cockroach control, consider using Shennong 2.1% cockroach gel bait.

Continuous use over the past few years has led to a high level of resistance, and the substance has already been banned for use on rice in China.

Methods for Seed Treatment (using a 600 g/L, 48% suspension concentrate/suspension seed coating as an example)

It can be used in combination with another piercing-sucking insecticide (acetamiprid).

〈1〉: Large-grain crops

1. Peanuts: Mix 40 ml with 100–150 ml of water to coat 30–40 jin of seeds (enough for one mu of land).

2. Corn: Mix 40 mL with 100–150 mL of water to coat 10–16 jin of seeds (enough for 2–3 mu of land).

3. Wheat: Mix 40 mL with 300–400 mL of water to coat 30–40 jin of seeds (enough for one mu of land).

4. Soybeans: Mix 40 mL with 20–30 mL of water to coat 8–12 jin of seeds (enough for one mu of land).

5. Cotton: Mix 10 mL with 50 mL of water to coat 3 jin of seeds (enough for one mu of land).

6. Other legumes: peas, yardlong beans, common beans, green beans, etc.—mix 40 mL of the product with 20–50 mL of water to coat the seeds for one mu of land.

7. Rice: Apply 10 mL per mu during seed soaking; sow after the seeds have begun to show white radicles, and keep water application to a minimum.

II: Small-grain crops

For rapeseed, sesame, and canola, mix 40 mL of the product with 10–20 mL of water to coat 1–1.5 kg of seeds.

III: Underground Fruits and Tuber Crops

Potatoes, ginger, garlic, Chinese yam, and similar crops are typically treated by mixing 40 ml of the product with 1.5–2 kg of water to coat the seeds for one mu of land.

IV: Transplantable Crops

Sweet potatoes, tobacco, and vegetable crops such as celery, scallions, cucumbers, tomatoes, and peppers.

Instructions for use:

1. Transplanted with nutrient-rich soil

40 ml, mixed with 15 kg of crushed soil and thoroughly blended with nutrient-rich potting soil.

2. Transplanted without a nutrient-rich soil ball

Use 40 mL of water, ensuring it just covers the roots of the seedlings. Before transplanting, soak the seedlings for 2–4 hours, then mix the remaining water with crumbled soil to form a thin slurry, and dip the roots in this slurry before planting.

Source: Fertilizer and Pesticide Assistant