Seed Treating Products
1. Organo Mercurial:
Organo mercurials are recommended for the treatment of small grains, flax, cotton and safflower. Proper dosage is critical. Over-treatment, however, may result in seed injury and under-treatment may fail to adequately control disease.
In general, the seed treated with the more volatile organic mercury compounds cannot be stored for more than a few days without lowering the viability of the seed, especially if the moisture content is high. The rate of application of organo mercurials should be watched closely. It should never be applied at more than the recommended rates. If the seed is to be stored for a while after treatment with a volatile fungicide, the moisture content of the seed should be below thirteen per cent.
2. Inorganic Mercurial:
The use of inorganic mercurial’s for treating seeds is practically limited to mercuric chloride, mercurous chloride and mercuric oxide. These materials when used are limited primarily to seeds, roots , tubers, garden and vegetable crops. Extreme caution’s is necessary in using inorganic mercurials for seed treatment. Mercuric chloride is injurious to some extent, to most seeds.
1. Organic non-mercurial:
The use of organic non-mercurial such as Thirum and Captan has considerably increased in the recent past. Generally, they are less effective than the organic mercurial but are less damaging to the seeds and less dangerous to persons handling the seed. Excessive dosages are not harmful to the seed which may be stored for long periods of time without suffering injury from the treatment. Organic non-mercurial are not determined to the viability of injured seed. These fungicides act as seed disinfectants and or seed protectants. That is ,they may kill fungal spores on the surface of the seed and also serve as a protectants to the seed against soil-borne organisms.
Copper carbonate, copper sulphate, cuprous oxides constitute the major inorganic non-mercurial compounds which are used as fungicides. Copper carbonate and copper sulphate are used as fungicides. Copper carbonate and copper sulphate are used on wheat as bunt preventives. Cuprous oxide prevents seed decay and damping-off vegetables, but is injurious to seeds of lettuce , crucifer and onions.
Insecticides are finding increased use in seed treating. These may be merchandised in combination with the fungicide, or as distinct products for individual use, or combined with the fungicide in the treating process. The uses include:
1. Protection against storage insects,
2. Protection against certain soil insects that the attack the seed.