The differences of these two affections of wheat may be expressed as follows:—
| Bunt. | Ear-cockle.. |
| Grain smooth externally, sometimes appearing black from blackened interior grains showing through the thin epidermis (bran). These corns easily crush beneath the finger, emitting the black fungi. | Grain cockled and irregular in shape, purple externally, skin thickened, interior of the grains stuffed with a white cottony substance, not compressible by the finger; but being opened, and the interior magnified, exhibits the living wheat-eels. |
As regards the ear-cockle, we incline to the belief that a damp atmosphere and cold soil are chiefly concerned in its spread, if not in its production. As we have shown the difference between it and bunt, we now proceed to offer a few remarks upon the production of the latter, and its remedies.
Bunt is mainly produced by defective seed. It occurs on all kinds of soils—sands, clays, and limestones—and is not peculiar to any climate. Professor Henslow believes the disease to be wholly propagated by the spores of the fungus adhering to the wheat-seed. He says, “It has been clearly proved that wheat plants may be easily infected, and the disease thus propagated, by simply rubbing the seeds before they are sown with the black powder or spores of the fungus. It is also clearly ascertained that if seeds thus tainted be thoroughly cleansed, the plants raised from them will not be infected;” and he deduces from this a proof in favour of steeping; for he says, “This fact is now so well established, that the practice of washing or steeping seed wheat in certain solutions almost universally prevails.”[17]
[17] See an essay on Diseases of Wheat, in the Journal of the Royal Agricultural Society for 1841, by the Rev. Professor Henslow.
Our own experiments, however, recorded in the “Journal of the Royal Agricultural Society” for 1856, led us to conclude that the success derived from pickling wheat in different caustic and corrosive solutions arose from the fact of diseased grain being destroyed in the process; and we extract the following record of experiments made in 1853, as explaining this view of the matter.
Four plots of wheat, all from the same sample, were sown in the following order:—
| 1. | 2. | 3. | 4. | |||
| Much diseased wheat, without pickle. | Much diseased; treated with sulphate of copper. | Perfect picked seed, without pickle. | Perfect picked seed, with sulphate of copper. |
The results of these were as under:—
Plot 1. Most of the seed germinated, but the crop was much blighted, both in straw and grain; in fact, scarcely a perfect ear of the latter.