TREATING WHEAT ON FARM

Press, Volume CVI, Issue 31119, 23 July 1966, Page 10

TREATING WHEAT ON FARM

TfECENTL? on these pages • Dr. R. C. Close, of the Plant Diseases Division of the Department of Scientific and Industrial Research, referred to interest among fanners handling their wheat in bulk, in treating their seed wheat on the farm with fungicides to control diseases like stinking smut. He discussed the i use of both liquid mercury ' preparations and non-toxic fungicides and suggested that there might be a place for portable slurry machines operated by contractors to do this job. Mr J. W. Crombie, of Waitohi, in the Temuka district, has been treating seed wheat for about four years now. In the most recent season he did about 70 to 80 sacks for his | own requirements. His wheat goes over a idresser before being treated, I and from the point of view of iease of drilling, Mr Crombie I sees some advantage in havI ing a dresser available to do this job, but he says that a ’well harvested line of wheat i would no doubt be quite sat- | isfactory. From the dresser the wheat I is elevated up and drops 'down a chute into a hopper i where a strictly regulated quantity of a liquid mercury ' chemical, Panogen, drips (down on it before it is lifted ; up again by a 3in auger. ! For effective treatment of I the seed wheat and to ensure : that there is no overdose and subsequent effect on germina|tion, there has to be a close

relationship between the amount of wheat coming off the dresser and the amount of chemical being applied tothe seed. A little more than a bushel of wheat a minute comes off Mr Crombie’s dresser and a carefully regulated quantity of chemical at the rate of three-quarters of a fluid ounce to a bushel is applied to the wheat. The chemical Is held in a tin with a cloth over the top to prevent any foreign matter getting into it and interrupting the flow—often a plastic bottle is used for this purpose and Mr Crombie says that this would be ideal. A plastic tube carries the chemical down to an eye dropper through which it feeds into the hopper at “something between a drop and a run,” to use Mr Crombie’s words. The eye dropper fits through a hole in a board clamped above the hopper. The flow of the chemical can be Increased or reduced by lifting or lowering the tin. A measuring glass is used before the treatment begins to ascertain that exactly the correct amount of chemical is dripping through in a minute in relation to the quantity of wheat coming through. On average the fall between tin and dropper Is only about two inches.

Now the treated wheat is augered up and drops down into a bin on the back of a motor-truck and is bagged off from there. In the auger mixing takes place helping the treatment process. Mr Crombie notes here that it Is probably undesirable for the auger to be working too greatly under capacity as it could result in damage to the seed. Mr Crombie says that because of the subsequent fumigant action of the chemical in the bags it is not strictly necessary to have some of the chemical applied to every single seed. But an examination of a treated sample shows that it has a uniform reddish tinge in comparison with the untreated wheat, and it looks as though most seeds do in fact receive some chemical. On the Crombie farm the treatment is done inside the granary and because liquid mercury is highly poisonous the doors are flung wide open and care is taken not to get the chemical on the hands. Mr Crombie says that no adverse effect on the germination of this home-dressed seed has been noted and a big advantage has been the reduced cost of the treated seed as compared with that purchased through normal commercial channels —Mr Crombie puts the saving for Hilgendorf at about 8s or 9s a bushel. He puts the cost of materials used as only about 3d a bushel.