Dual Gold

Dual Gold

1 Trade name	Manufacturer	Form
DUAL GOLD HERBICIDE	SYNGENTA CROP PROTECTION PTY LIMITED	EC

ACTIVE INGREDIENT: METOLACHLOR 960 g/L

4 CHEMICAL GROUP: K.

AMIDE or CHLORACETAMIDE

FORMULATION: Liquid

5 RELATED HERBICIDES: Alachlor

6 GENERAL DESCRIPTION:

Metolachlor is a mainly absorbed through the germinating shoots and roots. It is translocated through the plant and has a short residual life in the soil. It will control many grasses and some broadleaved weeds. Its main use is for pre-emergent weed control in cereals, vegetables and pastures It presents little hazard to the environment.

7 APPLICATION METHODS AND TIPS:

Metolachlor is normally applied to bare soil or in combination with a knock down herbicide. Rainfall is important to wash the herbicide from plant residue into the soil. High plant residue levels may reduce weed control (eg. 4 t/ha wheat straw reduced weed control by 20%). For grass weed control, the ideal placement for metolachlor is just above the germinating seeds. Deeper incorporation appears beneficial for broadleaved weed control. This may be due to metolachlor being more efficiently absorbed by shoots and cotyledons of grasses compared to roots and vice versa for broadleaved species.

Plant cereal crops at least 4 cm deep. Crop damage may occur on light soils and/or when heavy rain occurs within a few days of spraying.

Metolachlor should not be applied to wetlands.

15 REPLANTING INTERVALS:

Crop	Time
All unregistered crops	6 months

16 WITHHOLDING PERIODS:

Crop	Type	Time
All	Harvest
All	Grazing

17 RE-ENTRY PERIOD:

Wear protective clothing if re entry before the spray has dried.

24 TOXICITY:

Repeated exposure may cause allergic disorders.

Mammalian toxicity - low.

Acute oral LD50 - 2780 mg/kg (rate)

Acute dermal LD50 - 10,000 mg/kg (rabbit)

Skin - not irritating

Eye - Will damage eyes.

Vapour Inhalation LC50> 1.7 mg/L - non toxic.

Chronic Oral Toxicity - NOEL 100 - 300 ppm.

Tentatively classified as showing limited evidence of carcinogenicity in animals.

It is not teratogenic or mutagenic (does not cause reproductive effects).

Birds - low toxicity (LD50 2510 mg/kg)

Fish - moderate toxicity (LC50 4 - 10 ppm)

Invertebrates - low toxicity (LC50 25 ppm).

26 FIRST AID:

Contact Poisons Information Centre on 13 11 26.

If Swallowed - Contact a doctor.

If in Eyes - Flush with water for 15 minutes.

If on Skin - Wash with soap and water.

20 MODE OF ACTION:

Metolachlor is absorbed by the roots and young leaves (coleoptile) of all germinating plants. It requires moist soil and rainfall to wash it into the top few centimetres of soil to be effective. It moves mainly in an upward direction and inhibits plant growth. The primary biochemical mechanism is unknown. Growth inhibition is due to a reduction in both cell division and enlargement. Longitudinal growth is reduced more than lateral growth. This results in a compact appearance of affected roots. Protein and fat synthesis, respiration, lignification and anthocyanin production are reduced. Hormonal effects also occur resulting in hormone like symptoms.

Selectivity of metolachlor is due to the ability of tolerant plants to metabolise the herbicide more rapidly than sensitive plants. A number of commercial safeners and antidotes are used in conjunction with metolachlor to increase selectivity in crops.

Within the plant metolachlor is degraded by conjugation with gluthianone, deamination and side chain cleavage.

23 PLANT SYMPTOMS:

Seeds normally germinate but often fail to emerge. Seedlings that do emerge have stunted and abnormal growth. The first leaf may fail to unfold. Roots are stunted and compact. Leaf senescence may be delayed.

27 ENVIRONMENTAL FATE:

Metolachlor is degraded mainly by microbes in the field. The half life is normally 3 to 8 weeks and may be up to 12 weeks under cold, dry conditions in silty soils. The half life is usually longer in clay loams than sandy loams which is contrary to most other herbicides.

Volatilisation, photodecomposition surface runoff and leaching only account for minor amounts of degradation.

Metolachlor degrades in both aerobic and anaerobic conditions and in waterlogged soils. Thus contamination of ground water supplies is unlikely to cause significant problems. However, in the U.S.A. where large amounts of this herbicide are use it has been recorded, in some tap water samples and in ground water, in two states. It is not strongly bound to soils. Soil type only has a minor effect on the degree of binding.

Metolachlor is rapidly metabolised and almost totally excreted in the urine and faeces with a half life of approximately 24 hours. There is little build up in the tissues of animals.

Metolachlor should not be applied to wetlands.

Trade Name

Manufacturer

Dual Gold

2.	Concentration of Active Constituent : 960 g/L
3.	Formulation : Emulsifiable Concentrate
4.	Poison Schedule : 5
5.	Trade name : Dual Gold - Novartis
6.	Product Colour : Yellow to brown liquid.
7.	Product Flammability : Flammable.
8.	Dangerous Goods Class :
9.	Shelf Life : In excess of 2 years.
10.	Mixtures Compatibility : Flowable Gesaprim (atrazine)
11.	Registered Crop(s) : Wheat, Barley, Pastures.
12.	Effect of Soil Texture on Herbicide : Poor seed bed can result in uneven spray cover and weed germination to escape through 'holes' in the herbicide barrier. Leaching is inhibited by high clay and/or silt content.
13.	Effect of Soil pH on Herbicide : Not significant.
14.	Effect of Soil Organic Matter on Herbicide : Rapidly adsorbed by organic matter. Organic matter is the main constituent determining leaching behaviour as metolachlor is rapidly adsorbed. Crop damage is more likely on soils with low organic matter.
15.	Mode of Action : Affects coleoptile absorption of nutrients, germinating monocotyledon seedlings absorb most metolachlor through the shoots, just above the seed. Dicotyledon plants appear to absorb the herbicide through both shoots and roots. Short residual pre-emergent.
16.	Application Timing : Immediately after planting and before crop and weeds have emerged.
17.	Rate Variation : 300 to 500 mL/ha.
18.	Rates Selection : Lower rate in dry areas or when shorter residual control is required or in situations where crop competition is strong. Higher rate in wet areas or when longer residual control is required or in situations where crop competition is minimal.
19.	Crop Damage (Crop Tolerance) :
20.	Effect on Crop : Good crop tolerance.
21.	Effect on Clover Species : Clovers have good tolerance. In trials Trikkala sub-clover; Haifa white; Maral Persian; Paradanna; Balansa and Redquin showed excellent tolerance to maximum registered rate.
22.	Soil Moisture at Application :

DRY - Reduces effectiveness.

MOIST - Necessary for good results.

WATERLOGGED - Favours toad rush over crop, thus increasing pressure on herbicide and necessitating use of maximum label rate.

23.	Frost Effects : Not applicable.
24.	Frost Free Days Required After Application : Not applicable.
26.	Recommended Water Volume : Sufficient to give good coverage of soil with equipment used. Minimum of 60 L/ha stated on label.
27.	Nozzle Type : Flat fan or hollow cone.
28.	Recommended Nozzle Pressure : Follow manufacturer's recommendations.
30.	Recommended Wetter : Nil.
31.	Other Additives : Not applicable.
32.	Rain Fastness : Not applicable.
33.	Time Interval Before Effect is Noticed : Effects noted as reduced weed numbers reaching seedling stage.
36.	Withholding Period : Nil.
37.	Plant-Back Period : 6 months except for certain tolerant crops specified on the label.
38.	Spray Tank Clean-Up : Wash thoroughly with clean water after use.
39.	Other Comments : Apply after sowing and before crop and weeds emerge. Sufficient rain is needed within 10 days to move the Dual into the soil. If rain does not fall within this period lightly incorporate.

33 REFERENCES:

Acknowledgments:

Collated by HerbiGuide. For more information see www.herbiguide.com.au or phone 08 98444064.