Atrazine's main formulations include: 97% TC, 50% and 80% WP, 38% and 40% SC, and 4%, 8%, and 20% granules. It is a selective pre- and post-emergence herbicide. It controls annual broadleaf weeds and grasses, with better control of broadleaf weeds than grasses, and also has some inhibitory effect on perennial weeds. Apply 200-250 ml of 38% Atrazine SC per acre before weeds emerge or when they are in the 1-3 leaf stage. Due to its long-lasting effect, it is often mixed with other herbicides in production to reduce dosage and minimize phytotoxicity.
Excellent effectiveness (over 90%) on weeds: Amaranthus retroflexus, Chenopodium album, Purslane, Abutilon, Polygonum, Goosegrass, Setaria viridis
Moderate effectiveness (70-90%) on weeds: Echinochloa revoluta, Digitaria sanguinalis, Atractylodes lancea, Solanum nigrum
Poor effectiveness (50-70%) on weeds: Amaranthus truncatula
Very poor effectiveness (less than 50%) or ineffective on weeds: Morning glory, Field bindweed, Cyperus rotundus
However, atrazine is a long-lasting pre-emergence herbicide with a half-life of 35-50 days in the soil. Clayey soil particles strongly absorb the agent, resulting in a longer residual effect and frequent damage to subsequent crops.
Different corn varieties have varying tolerance to atrazine. Therefore, it should not be used in inbred corn lines, sweet corn, glutinous corn, popcorn fields, or corn seed fields. It's best not to apply atrazine to sweet corn fields to avoid phytotoxicity.
When using atrazine, if the liquid drifts due to wind or improper application, it can cause leaf yellowing or curling in neighboring watermelons, cucumbers, beans, peaches, poplars, and jujube trees, and in severe cases, leaf loss. Crops such as wheat, rice, spinach, cucumbers, watermelons, tomatoes, cabbage, cauliflower, kale, and rapeseed are particularly sensitive to atrazine.
In soil, if atrazine residues exceed 0.080 mg per kilogram, cabbage growth will be significantly inhibited; if it exceeds 0.104 mg, cabbage growth will be abnormal; and if it exceeds 0.081 mg, direct-seeded japonica rice growth will be abnormal. In other words, even the slightest amount of atrazine residue in the soil can cause growth problems for these atrazine-sensitive crops.
Very weakly resistant crops: cucumbers, watermelons, peaches, millet, and rice.
Based on local conditions, careful attention and caution can be taken when rotating crops and applying atrazine to reduce or avoid unnecessary losses. It is widely recognized in the industry that runoff or leaching from atrazine applications can pollute groundwater and surrounding water sources. Negative reports on atrazine have also been reported in Europe and the United States, with reports of significant impacts on frog reproduction due to water pollution and human health effects.
1. Deeply till the soil. Start by turning it once with a deep plow to move any atrazine residue from the topsoil to the ground below.
2. Apply biofertilizer and well-rotted farmyard manure to accelerate the decomposition of residual atrazine. Rotary till the soil two to three times after application.
3. Change to sorghum or transplant fruit trees first. However, when planting fruit trees, treat the roots with rooting powder to accelerate new root growth.
4. Combine soil disinfection with soil disinfection to prevent soil-borne root diseases. Some experiments have found that treating the soil with dichlorodiphenylmethane can also reduce residual atrazine damage.
5. Using ammonium nitrogen fertilizer can also reduce atrazine damage to crops.
