Diflufenican 30% SC Herbicide: Precision Weed Control for Cereal Crops

Technical Specifications

Mode of Action

1. Absorption Routes
   • Shoot Absorption: Primarily, diflufenican is absorbed by the shoots of germinating seedlings. Once the herbicide comes into contact with the emerging shoots of weeds, it quickly penetrates the plant tissues.
   • Limited Root Uptake: Although root uptake is not the main pathway, there is some absorption by the roots of young weeds, especially in the early stages of germination.
2. Biochemical Disruption
   • By inhibiting phytoene desaturase, diflufenican blocks the biosynthesis of carotenoids in the target plants. Carotenoids are essential for protecting chlorophyll from photo – oxidation. Without carotenoids, the chlorophyll in the weed cells becomes vulnerable to damage from sunlight.
3. Symptom Progression
   • Initial Bleaching (3 – 5 days): In the early days after application, the first visible symptom is the appearance of bleaching or whitening in the young leaves and shoots of the weed. This is due to the destruction of chlorophyll caused by the lack of carotenoid protection.
   • Growth Inhibition and Necrosis (7 – 14 days): As the carotenoid deficiency persists, the bleaching spreads throughout the plant. The weed’s growth is severely inhibited, and eventually, the leaves wilt, turn brown, and die, leading to the complete collapse of the weed.

Application Guide

Application Best Practices

• Water Volume: For ground applications, use 200 – 400 L of water per hectare. This volume helps in achieving even coverage of the herbicide over the soil surface (for pre – emergence) or the foliage of emerged weeds (for post – emergence). In aerial applications, adjust the water volume according to the specific guidelines of the application equipment, ensuring proper distribution.
• Adjuvants: Adding a non – ionic surfactant at a rate of 0.2 – 0.5% v/v can enhance the performance of Diflufenican 30% SC. The surfactant improves the wetting and spreading of the herbicide on the leaf surface (for post – emergence applications) and aids in better soil penetration and adsorption (for pre – emergence applications).
• Tank Mixes
  • In wheat fields, Diflufenican 30% SC can be tank – mixed with isoproturon to control both broadleaf and some grassy weeds more comprehensively. For example, a combination of diflufenican and isoproturon can target both galium and wild oats effectively. However, always conduct a jar test before large – scale tank mixing to ensure compatibility.
  • In barley fields, it can be combined with flufenacet for enhanced broad – spectrum weed control. Flufenacet is effective against grassy weeds, and the combination with diflufenican can control a wider range of weed species.
• Weather Conditions: Apply on calm days with temperatures between 10 – 25°C. Avoid spraying when rain is expected within 24 hours, as rain can wash away the herbicide before it has a chance to be absorbed by the weeds or penetrate the soil. High – temperature conditions can increase the volatility of the herbicide, so it’s best to avoid applications during extremely hot weather.

Key Advantages

1. Broad – Spectrum Broadleaf Weed Control
   • Diflufenican 30% SC can effectively control over 40 different species of broadleaf weeds. This includes many common and troublesome weeds in cereal fields, such as pigweed, shepherd’s purse, chickweed, and wild mustard. Its broad – spectrum activity makes it a valuable tool in integrated weed management programs, reducing the need for multiple herbicide applications.
2. Residual Activity
   • It provides significant residual soil activity. After pre – emergence application, the herbicide remains in the soil for several weeks, preventing the germination of new weed seeds. This residual activity can last for 4 – 6 weeks, depending on factors such as soil type, temperature, and moisture. As a result, it helps in maintaining a weed – free environment in the treated area for an extended time.
3. Crop Safety
   • When applied at the recommended rates, Diflufenican 30% SC shows excellent selectivity in wheat, barley, and rye. These crop plants are able to tolerate the herbicide well, while the target weeds are unable to withstand its effects. In some cases, such as in barley when applied pre – emergence, there may be a slight temporary discoloration of the crop leaves if there is heavy rainfall after application, but the crop usually recovers quickly.
4. Flexible Application Options
   • It can be used both pre – emergence and in early post – emergence stages. Pre – emergence applications target germinating weed seeds, providing early – season weed control. Early post – emergence applications can be used to control small, emerged weeds. This flexibility in application timing allows farmers to choose the most appropriate method based on the weed growth stage and field conditions.
5. Resistance Management
   • As part of an integrated weed management strategy, diflufenican can be rotated with herbicides from different mode – of – action groups. This helps in reducing the selection pressure for resistant weeds, ensuring the long – term effectiveness of weed control measures.

Safety & Environmental Notes

• Toxicity
  • Mammalian Toxicity: Diflufenican has relatively low mammalian toxicity. The oral LD₅₀ (rat) is greater than 2000 mg/kg, indicating a low risk of acute toxicity to humans and animals if ingested. However, proper handling and safety precautions should always be followed when using the product.
  • Aquatic Toxicity: It has moderate toxicity to fish and aquatic invertebrates. Avoid direct application into water bodies or areas where runoff is likely to enter water sources. Maintain a buffer zone of at least 50 meters from water bodies during application. In case of accidental spills near water, take immediate measures to contain and clean up the spill to prevent water contamination.
• Environmental Fate
  • Soil Degradation: In soil, diflufenican degrades mainly through microbial action. The half – life in soil (DT₅₀) typically ranges from 14 – 28 days, depending on factors such as soil type, temperature, and moisture. In well – drained, warm, and moist soils, the degradation process is relatively faster. This relatively short half – life helps in minimizing long – term soil residues and reduces the risk of carry – over effects on subsequent crops.
  • Volatility: Diflufenican has low volatility. This reduces the risk of vapor drift to non – target areas, such as neighboring crops or sensitive habitats. However, proper application techniques, such as using appropriate nozzles and application pressures, should still be followed to avoid any potential off – target movement.
• Storage
  • Store Diflufenican 30% SC in a cool, dry place away from direct sunlight. The storage temperature should be maintained between 5 – 30°C. Keep the product in its original, tightly – sealed container to prevent contamination and maintain its efficacy. Store it out of reach of children, pets, and food products.

Packaging & Compliance

• Standard Packs
  • Available in 1 – liter, 5 – liter, and 20 – liter HDPE (High – Density Polyethylene) containers. These containers are designed to be leak – proof, durable, and easy to handle. They are clearly labeled with product information, safety instructions, application guidelines, and relevant regulatory information.
• Custom Solutions
  • For large – scale agricultural operations or distributors, custom packaging options may be available. This can include private labeling with specific brand names and multilingual instructions to meet the needs of different regions.
  • The product complies with all major regulatory requirements in various countries. In the European Union, it meets strict regulatory standards. In the United States, it is registered with the EPA. Regulatory support can be provided for countries in Asia – Pacific, South America, and other regions to ensure proper registration and use.
• Shelf Life
  • Under recommended storage conditions, the shelf life of Diflufenican 30% SC is 2 – 3 years. Regularly check the product for any signs of degradation, such as separation, clumping, or changes in color or odor, before use. If any signs of degradation are observed, do not use the product and contact the manufacturer for further advice.

FAQ

1. Can Diflufenican 30% SC control grassy weeds?
   • While its primary target is broadleaf weeds, in combination with other herbicides (such as flufenacet or isoproturon), it can contribute to the control of some grassy weeds like wild oats in cereal fields. However, it is not as effective against grassy weeds when used alone.
2. What is the pre – harvest interval (PHI)?
   • Wheat: The PHI is typically 60 days. This means that the last application of Diflufenican 30% SC should be made at least 60 days before the wheat harvest to ensure that no harmful residues remain in the harvested crop.
   • Barley: The PHI for barley is around 70 days.
   • Rye: The PHI for rye is approximately 65 days. Always check the product label for the most accurate and up – to – date PHI information, as it may vary slightly depending on local regulations and specific crop varieties.
3. Is it safe to use near water sources?
   • Due to its moderate aquatic toxicity, Diflufenican 30% SC should be used with caution near water sources. Maintain a buffer zone of at least 50 meters from water bodies during application. Avoid spraying on slopes where runoff is likely to carry the herbicide into water sources. In case of accidental spills near water, take immediate measures to contain and clean up the spill to prevent water contamination.
4. How can I manage herbicide resistance when using Diflufenican?
   • Rotate Diflufenican with herbicides from different mode – of – action groups. For example, in one season, use Diflufenican, and in the next, use a Group 2 (ALS inhibitor) or Group 15 (acetamide – type) herbicide. Also, avoid consecutive annual applications of Diflufenican in the same field. Mixing it with other herbicides with different modes of action can also help in reducing the selection pressure for resistant weeds. Regularly monitor the weed population in your fields for any signs of resistance development and adjust your weed management strategy accordingly.
5. Can it be used in organic farming?
   • No, Diflufenican is a synthetic herbicide and is not approved for use in organic farming systems. Organic farming relies on non – synthetic methods such as mechanical weeding, mulching, and the use of certain approved natural herbicides.

Field Performance

• Wheat Field Trials in the UK: In a series of field trials over multiple seasons, application of Diflufenican 30% SC at 180 g ai/ha (pre – emergence) provided over 90% control of common broadleaf weeds like galium and veronica. When tank – mixed with isoproturon, the control of annual meadowgrass (a grassy weed) was also significantly improved. This led to an average yield increase of 10 – 15% compared to untreated plots.
• Barley Farms in Germany: At a dosage of 220 g ai/ha, Diflufenican effectively controlled broadleaf weeds such as shepherd’s purse and chickweed, with control rates reaching up to 92%. When combined with flufenacet, the overall weed control in barley fields was enhanced, resulting in better – quality barley grains and an average yield improvement of 8 – 12%.

Residue Limits