Science and Practice in Farm Cultivation Part 21

CHAPTER XXVII.

ON THE SUPPOSED ORIGIN OF BARLEY AND RYE.

The cereal barley is found to offer three important forms, which can be best explained by the annexed diagramatic arrangement:-

[Ill.u.s.tration:

_Two-rowed-by abortion of four_

_Four-rowed-by abortion of two_

_Six-rowed-by fruition of all_

_the seeds of a spikelet._]

The two-rowed barley has been named _Hordeum distichum_; and as we are inclined, with Professor Lindley, to the belief that this is the original from whence the other forms have sprung, we here quote the learned Professor's remarks upon this and the probably allied forms:-

"It is probable," he says, "that all kinds of barley grown by farmers are varieties of one species, of which, the _H. distichum_ of Linnaeus is the type. The spikelets of this genus always standing in threes, and the threes being placed back to back, it is evident that every ear of barley must consist of six rows of spikelets. If the middle spikelet of each set of threes is alone perfect, the side spikelets being abortive, we have _H. distichum_, the common two-rowed barley, and its many varieties; if the two-tuberal of each set is perfect, and the central spikelet imperfect, as sometimes happens, then we have four-rowed barley; if, on the other hand, all the spikelets are perfect, we have six-rowed barley, or _H. hexastichum_; but the cases of four-rowed barley have been merely accidental-they may be referred to the six-rowed form; and thus we have only two princ.i.p.al kinds of barley-namely, _H.

distichum_ and _H. hexastichum_.

"1. _H. distichum._-This is the only kind of barley that has been found apparently wild. We have now before us specimens gathered in Mesopotamia during Col. Chesney's expedition to the Euphrates, with narrow ears, a little more than an inch long, exclusive of the awn, or four and a half inches awns included; and others from the ruins of Persepolis, with ears scarcely so large as starved rye. Both are straw-colour, but that from Mesopotamia has the glumes much more hairy than the other. The plant is also said to inhabit Tartary.

The report that it grows wild in Sicily seems to have arisen from the Mediterranean _aegilops ovata_ having been mistaken for it. To this species belong all the varieties, from one to sixteen, formerly mentioned under Barley; as also does No. 20, fig.

34[14]-the _H. zeocriton_, sprat or battledore barley, an undoubted result of domestication, chiefly remarkable for the ears being so much broader at the base than the point as to produce a long ovate figure.

[14] See Morton's _Cyclopaedia of Agriculture_.

"2. _H. hexastichum._-We found no record of this having been found wild, and presume it and its numerous varieties to be domesticated forms of _H. distichum_. The common bere, or winter barley, may be taken as the typical form to which Nos. 18, 21, and 22, and figs.

37 and 38[15] are evidently referable, varying in size, colour, and hairiness, more than in any other circ.u.mstance deserving botanical appreciation.

[15] Ibid.

"The _H. vulgare_ of Linnaeus is a form with the grains in four rows, the naked-eared variety of which is again the _H. cleste_ of some writers.

"Both these forms of barley vary with naked seed, the pales losing their adhesion to the grain. But this difference is attended with no other peculiarity.

"3. The _H. trifurcatum_, also known under Dr. Royle's name of _H.

aegiceras_, is a very remarkable naked-seeded species, with much the appearance of wheat. It is a tall or glaucous six-rowed sort, but the rows are not placed in lines with the same exactness as in the two former kinds, so that the ears are round like wheat. The pales are apparently in a monstrous form, the ends being three-lobed, and curved back in the form of horns, which sometimes extend into awns.

It has been introduced from the Himalaya Mountains within a few years, but its economical qualities remain to be determined."[16]

[16] _Cyclopaedia of Agriculture_, vol. ii. p. 68.

We have had opportunities, through the kindness of Professor Lindley, who contributed seeds, of cultivating all the forms just described; but our experiments for two years did not elicit anything new upon the subject: we therefore feel justified in quoting the above entire, especially as the different forms in our plots afforded sufficient evidence of an uniformity of origin on the one hand, with every disposition for forming varieties on the other.

Rye (_Secale cereale_).-For the little that is known of the natural history and origin of this crop-plant we again quote from the _Cyclopaedia of Agriculture_, which states as follows:-

"The common rye is a cereal gra.s.s, distinguished from wheat by its narrow glumes and constantly twin narrow florets, with a membranous abortion between them. Otherwise it is little different in structure, although the quality of its grain is so inferior.

According to Karl Koch, it is found undoubtedly wild on the mountains of the Crimea, especially all around the village of Dshimil, on granite, at the elevation of from 5,000 to 6,000 feet.

In such places, its ears are not more than 1 to 2 inches long. Its native country explains the reason why it is so much hardier than any variety of wheat, the southern origin of which is now ascertained."

We have not seen any of this so-called wild rye; it would, however, be of great service could some good experiments be made with it, with a view of noting the changes which take place on cultivation. Indeed, we have long wished for authentic examples of all our wild, or supposed wild, cereals, with a view of examining side by side the nature and amount of the changes which cultivation would most a.s.suredly produce.

Rye, unlike either wheat or barley, is not remarkable for a long list of varieties-a fact which may, perhaps, be attributed to the more limited growth of the former than the two latter. Its less extended cultivation must be attributed to its inferior qualities as food; for, though rye is in the main a hardier plant than wheat, and therefore could withstand the evils of a colder climate and colder treatment, yet with the advanced climate-the acclimatization of a country rather than a plant-the superior plant, wheat, everywhere prevails; and this cause also gives rise to the production of finer varieties, which are thus grown where only coa.r.s.er ones were possible.

CHAPTER XXVIII.

EPIPHYTICAL PARASITES (VEGETABLE BLIGHTS) OF CORN CROPS.

These forms of parasite are so numerous, that nearly every species of flowering plant may become the nidus even of several named genera, with many species, or, at least, varieties of them. We here say attacked, because the advent of many of their forms pa.s.ses under the name of "blight;" a term which at once recognises their injurious tendency.

Whether these epiphytes are the causes of the so-called blighted conditions, or merely their effects, is a subject upon which no little discussion has been expended. We do not, however, mean to re-open the question here; we will only remark, that in all probability this very wide range of the lower tribes of the vegetable kingdom is very variable in these respects.

Again: it will be impossible to enter into details of the different species of epiphytes. We shall hope, therefore, to elucidate their natural history, in so far as the farmer is concerned, by pointing out the more general facts connected with the following forms:-

1. _Uredo segetum_-s.m.u.t or dust-brand of wheat, barley, and gra.s.ses.

2. _Uredo caries_ (_Tilletia_)-Bunt } } 3. _Uredo rubigo_-Red gum or red robin } } of wheat.

4. _Uredo linearis_ } } }-Straw-rust, or "mildew" } 5. _Puccinia graminis_ } }

6. _Puccinia fabae_-Bean-rust.

7. _aecidium berberidis_-Barberry-rust.

8. _Cladosporium herbarum_-Corn-ear mould.

9. _Botrytis infestans_-Potato-mould and mildew.

10. _Botrytis_-Turnip-mildew.

11. _Odium erysiphioides_ } } Hop-mildew.

12. _Erysiphe macularis_ }

13. _Odium abortifaciens_-Ergot of gra.s.ses.

1. _Uredo segetum_, s.m.u.t or Dust-brand, is common to barley, and not unfrequent in wheat; in both of which crops it is easily recognised from the affected ears of corn appearing as though they had been powdered over from the sweep's soot-bag. On closely examining these blackened ears, we find that the whole flower has, as it were, effloresced into a black powder, which, on being placed under the microscope, is shown to be composed of myriads of granules, called by the fungologist _spores_, in which latter are contained still smaller grains, or _sporidia_.

These black spores are all washed away by the time the crop is ripe, leaving the stalks bare and grainless, so that the sample suffers no injury from this blight, which, even if present after threshing, would only tend to a slight discoloration of the sample, which is remediable by the s.m.u.tter. Its chief effect, however, consists in causing the loss of much grain. We have observed it to the extent of as much as an eighth, but usually the diminution is about equal to the amount of seed sown; though it is not improbable that the whole crop may in many cases be greater when the s.m.u.t is present. Sheep-folding previous to barley, special manuring for this crop, and other causes of increased fertility, are constant causes of the increase of the dust-brand.

2. _Uredo caries_-Bunt, Pepper-brand, s.m.u.t-b.a.l.l.s.-This blight differs from the preceding in the fact that in the grain no flower is formed, but its interior becomes filled with a dark powder, which, when viewed under a high magnifying power, is found to consist of granules, with a surface which is rough, and not smooth as in the dust-brand.

In most cases, the whole grains of the ear will be so affected; in others, only a portion of them. They will be gathered in the harvest, and as the diseased grain is readily crushed, the black powder materially damages the appearance of the sample. Nor is this all: this blight has a most disagreeable odour and flavour, both of which are communicated to the sample, and so, besides diminishing the amount of produce, it greatly deteriorates it. Its specific name of _caries_ of course refers to this fact, as also does that of _U. ftida_, adopted by Baur, an author to whom we are greatly indebted for information upon these curious productions.

Before considering the remedy for this evil, it will be well to distinguish it from the "purples, ear-c.o.c.kle, or peppercorn" (_vibrio tritici_)-a name expressive of its animal origin, and frequently rendered "wheat-eels." In the purples, the grain is shorter than a healthy wheat grain, irregular in shape (c.o.c.kled), and purple externally; but its interior is filled with what, to the naked eye, is like very short white cotton-wool. On placing a bit of this woolly substance with the point of a needle on a slip of gla.s.s, just touching it with water and submitting it to a high magnifying power, the term "wheat-eel" will at once be seen to be justified; for, if alive, thousands of eel-like creatures will be seen writhing in the fluid.

The differences of these two affections of wheat may be expressed as follows:-