ADVICE TO FELLOW-GROWERS.

Nelson Evening Mail, Volume XLII, Issue XLII, 14 April 1908, Page 1

ADVICE TO FELLOW-GROWERS.

(Sydney "Daily Telegraph.") Some little time ago (writes Mr J. C. Watson, from Mudgee) I gave a short description in your columns of raj experiences in "bluestoning" wheat, and since then several farmers with whom I have lately been in contact have desired to know something more about the disease of wheat, etc., called smut. They kriow that carefully treat ing the seed with various solutions —es pecially sulphate of copper—mitigates to a marked extent the ravages of the disease, but why it does so they are in the dark. For the benefit of such a; these I give a detailed description of the operations of smut in the plant, and my own operations and experi monts extending over a good few years. For my earliest teachings on "smut" I am indebted to Marshall Ward", Pro fessor of Botany, and I have one of his pamphlets, and shall refer to it as oc casions arise. It is a common thing with many of us to see somo of the ears of wheat barley, or oats, in a field of grain pre senting a blackened. shrivelled ap pearance, totally different to the goldei colour of the ripe, full ears around, anc' if we were to gather some of thes< "smutted" ears, they would be founc' to be withered and full of a powder re sembling soot. This powder consists o! millions of minute, dark, roundis' spores of a fungus called ustilago. Th particular species which produces th smut or blackheads in our wheatfield: belongs to what may be called a ver; ancient family of fungi, and wa known to the Greeks and Romans, anc* caused a great stir in the world durin historic times. Tho agriculturists of that period used to think when thei: crops were blighted that it was the vi sitation of an offended deity, the blight ing influences of a thunderstorm, a punishment for some wrongdoing. Tcome to later times, only five years age I heard a farmer remark, when tli majority of his crop was blighted, that it was an angry visitation of Pro videncc for some of his sins. A groat deal of attention lias beei directed to these "smuts," and tin mystery attached to the subject ha always been a great attraction. Thi mystery has been cleared up by the ait of the microscope, and I shall give ir as simple language as possible th.reason why the smut gets into the ears and the part tho bluestone plays to pre vent it getting there. The seed graiis sown in due season, germinates, am everything goes on well to all appeal ances until the heads begin to fill anr ripen. Suddenly, as the grain is get ting near the time for harvesting, thfarmer finds a greater or a smaller pre portion of the ears smutty. Each bar' grain is filled to bursting with small dark, powdery spores. Each smut bal is made up of millions of these spore in the same way that many thousand: of grains of sand make up a handful only each spore has a little root, as i< were, that penetrates the grain, draw ing nourishment from the plant. I was once a puzzle as to how the fungu got into the plant at all. Comparin the behaviour of other fungi with tha of the smut fungus led many to sup pose that the black spores or grain fell on to the leaves or flowers of th wheat, and put forth their roots o fungus filaments into the plant. Aftei exhaustive experiments, and puttin;. many things together, it was found ou! that tho fungus enters the seedlini when it is still very young, grows uj with the plant, and does not show it self until the fruit or grain begins ti ripen, as we all well know. If we place some spores in a drop of water and keep at a right temp.eratun they will germinate and shoot out a short, very delicate tube loot. Tht safe thing happens when a grain of smut adheres to a grain of wheat; tht moist condition of the soil causes it te germinate as well as the cereal, and the roots of the smut penetrate th young and tender tissues of the bladt before it gets above ground. Once in side the young seedling, this germina' tube bores its way from cell to cell, un til it reaches the bud of tho shoot

takes up its abode there and keeps pac< I with the growth of the wheat through; all its months of growing, becomes master of the situation, and again pro duces its kind at the expense of the wheat. We will now see how the bluestonc ' acts, and I think many a farmer will shake his head when I say that blue stone will not kill smut. This is what it does, though. Bluestone is a poison, : and when we soak the wheat in the solution and dry again, a certain quanf j tity of dry powdered (precipitate) bluo- , ; stone is found adhering to the grain, ? i and when the sumt sends out its little roots they come in contact with the , bluestone, and are killed, and when the roots are dead the smut can do nc j further damage. We can cause wheat c ! to germinate in bluestone water, but " as soon as the little root or bud of the J" , wheat comes in contact with the solu 1 tion it is immediately killed ; there 1 fore, for the same reason, farmers .should see that the solution is strong ' I enough to kill the roots of smut while I not too strong to injure the bud of tbe j ] wheat. Farmers hove often been heard to remark that the smut is in the ground. Quite right, for some previous 'ly infected crop has. showered the spores on the ground ready to feed on , its host — the a'heat plant — as soon as opportunity offers. This I proved by exhaustive experiments. I secured some specially clean wheat, a handful, and subjected each grain to a minute mi , croscopical examination. Having satis- ! Red myself that no spores were en- I tangled in the hairs surrounding the I gram, I sowed in a plot which I knew . , contained smut from a previous bad j crop. It grew, and over 90 per cent, of j the heads were smutty. Alongside this i plot was sown other handfuls of wheat ' — proved perfectly free from smut by I the same careful examination — but treated with bluestone and various , other solutions by way of information. These samples grew, and produced , fine healthy heads without exception. I am still experimgiting with the other solutions, and up to the present have had marked success with boiled urine ; but of this later on. i There is one other little matter that I would like to draw attention to. It is a general plan for farmers to feed ■ their working horses on the dirty smutty grain that comes from the cleaner; also on the infected hay. The spores are able to pass through the ani mal uninjured, and are spread about the paddocks by means of the drop pings, and unless the pickling of the seed is thoroughly carried out, th< coming crop is sure to be smutty, ne matter how clean the seed may have been. We stand very little chance of ever getting rid of this djsease — still it does' not do to get disheartened, but strive to beat and keep it down by all means within our power, and the re ward shall be beautiful waving fields of golden grain, delighting the heart of man, and feeding the multitudes with snow-white flour, free from the ob- s. jectionable and pernicious spores of smut. jj'