Bordeaux mixture


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Related to Bordeaux mixture: hydrated lime

Bordeaux mixture

(bôrdō`), fungicide consisting of cupric sulfatecupric sulfate
or copper (II) sulfate,
chemical compound, CuSO4, taking the form of white rhombohedral crystals or amorphous powder. It decomposes at 650°C; to cupric oxide (CuO).
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 and lime in water. Its fungicidal activity is associated with the slow formation of copper compounds, the ultimate toxicant being the cupric ion. It originated in France in 1885 and was widely used for spraying orchards, dusting crops, and treating seeds until c.1930. Since it was found that Bordeaux mixture frequently caused russeting of fruit, injured the leaves, and led to premature defoliation, it has been generally replaced by solutions made with powdered fixed copper. Sal soda Bordeaux, or Burgundy mixture, containing cupric sulfate and sodium carbonate (sal soda), was formerly used to spray small fruits but has been replaced by more convenient preparations. See pesticidepesticide,
biological, physical, or chemical agent used to kill plants or animals that are harmful to people; in practice, the term pesticide is often applied only to chemical agents.
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Bordeaux Mixture

 

a widely distributed chemical used against fungous and bacterial diseases of plants.

Bordeaux mixture is prepared on the day of use. One kg of blue vitriol is dissolved in 90 liters (7) of water. While these ingredients are being mixed, 10 1 of freshly prepared milk of lime is added. This causes the precipitation of basic sulfuric salts of copper in the form of a gelatinous precipitate that covers the leaves and fruits of plants effectively.

Bordeaux mixture is used most frequently to prevent grapevine mildew, apple scab, pear scab, and spots on stone fruits. The period and quantity of application depends on the biological characteristics of the cause of the disease and on weather conditions. Plants are sprayed with a 3–5 percent Bordeaux mixture (blue spraying) until the buds open. At the time of vegetation, a 0.5–1 percent solution is used. Bordeaux mixture should not be acidic, or it will burn the leaves. It is slightly poisonous.

Bordeaux mixture

[bȯr′dō ‚miks·chər]
(materials)
A fungicide made from a mixture of lime, copper sulfate, and water.
References in periodicals archive ?
To start with, we used three dependent variables for estimation of equation (1): (a) Adopter of Bordeaux mixture [=1 if adopter of Bordeaux mixture (one or two times), =0 otherwise], (b) Adopter Systemic fungicides [=1 if adopter of Systemic fungicides (one or two times), =0 otherwise] and (c) Adopter of both Bordeaux mixture and Systemic fungicides [=1 if adopter of both Bordeaux mixture and Fungicides (one or two times), =0 otherwise].
Channels of communication for Bordeaux mixture and systemic fungicides are distinguished by fellow farmers and extension workers.
Make your own Bordeaux mixture with 9oz of copper sulphate, 6oz of quicklime in five gallons of water.
Spray potatoes with Bordeaux mixture every two weeks until September as a precaution against potato blight.
But it was 25 years before the Bordeaux mixture fungicide was developed - too late to stop the ravages of the great hungers of 1845-50.
Instead of waiting for the arrival of blight, spray against it with Bordeaux mixture in July and then once a fortnight until September.
I always water them in with a copper-based fungicide such as Cheshunt Compound, Traditional Copper or Bordeaux Mixture.
The only sure way of avoiding potato blight is to routinely spray plants with Bordeaux mixture or Dithane (mancozeb) before they become affected.
Spray peaches, nectarines and almonds again with a copper-based solution such as Bordeaux Mixture or Murphy Traditional Copper.
REMEMBER to water seedlings (especially those just pricked out) with a copper fungicide such as Cheshunt Compound, Traditional Copper or Bordeaux Mixture, to tend off damping off disease.
The blight responsible for the potato famines in Ireland remains a problem and while spraying from July every fortnight until September with Bordeaux mixture does help, it is probably easier to plant only blight resistant varieties.
WATER newly-sown seed and young seedlings with a liquid Copper or Bordeaux Mixture fungicide to prevent damping off disease.