THE WHEAT BUG

Press, Volume LXXII, Issue 21970, 19 December 1936, Page 11

THE WHEAT BUG

INCIDENCE AND CONTROL The quarterly report of the Wheat Research Institute gives much intuesting snd valuable information ab-.ut the suspected new pest of wheat called the "wheat bug." Description of the Injury In Turkey, Spain, and latterly in Germany, there has been found a bus, about a quarter of an inch long whicn sucks the sap of the developing wheal grain, and at the same time injects, into the grain a juice which after the grain is ripe causes it to make a very inferior flour with a sticky dough, in New Zealand certain sticky doughs havebeen noticed this year, and furthermore certain samples of wheat have been found with all the marks borne by the German wheat attacked by the wheat bug. These marks consist of a circular pale yellow opaque patch on the cheek of the grain, and in the middle of the patch there is, in well defined cases, an almost microscopic black mark, which is probably the place where the bug has inserted its proboscis. The whole thing is rathen like a miniature mosquito bite, with Us central puncture and inflamed circular area round it. The Insect in New Zealand j It is not probable that the insect j that attacks the grain in New Zealand is the same as that found in Turkey and Spain. Even in Germany it is not! the same bug, but a native one, which I used to suck the sap of weeds, and j has only lately attacked wheat. In! New Zealand there are at least a j dozen sap-sucking bugs, and the insti-1 tittc has arranged that an entomolo- j gist visit the suspected areas and try j to identify the insect causing the j damage here. If it proves to be a native, that will have an important bearing, on the probability of the attack recurring in future years. This year's attack may be only the effect of some peculiarity of the season. This is rendered somewhat probable by the impression held by some handlers oi wheat that they have seen the condition in former years, and by old records of very poor flours from areas now apparently showing bug attack. Distribution of the Attack The officers of Ihe institute have inspected stocks of wheat from most districts in Canterbury and Otago and have found some affected lines from nearly all wheat-growing areas in Otago. None has so far been found north of the Waitaki. Control or Remedy Little is known overseas of methods of warding off the insect attack, and therefore attention has to be concentrated on remedying the defect at the milling and baking stage. The first suggestion is that millers should avoid where possible the purchase of infected lines. If it becomes necessary to use them they can be safely used in small proportions, j There is nothing injurious to health, in the affected wheats, the damage j being caused merely by a special j enzyme in the wheat. On the Continent, where affected wheat is very much more common than here, serious j trouble in the bakehouse is completely avoided by judicious blending in the mill. Treatment of affected wheats has been largely studied in the laboratory of the institute. The hot conditioning! of wheat recommended in Germany has been tried with fairly satisfactory results, but any such process must be expensive and requires some special equipment. . Subjection of the flour to ultra violet rays produces a great improvement. If flours with sticky gluten reach the bakehouse, serious trouble may be avoided by modifications of the baking technique, which will be explained tu all bakers 'by the officers of the institute, if this becomes necessary. Many hundreds of loaves have been baked in the attempt to find the most .iuitable process to use, and every avenue of combating this new pest is being vigorously explored. The wheats of the coming harvest will be watched with special interest lo see if this bug damage is going to increase, or if it is only one of periodical troubles that come and go with the varying seasons.

The last sale of cattle at the corporation yards, Melbourne, where sales nave been conducted for the last (>4 years, was held on December 4. Amid fitting enthusiasm the sale of the last milch cow was conducted by an auctioneer who has held a license for 48 years. The sale was booked by a man who has been in the stock market for the same period. The animal sold was a dairy cow, which fittingly realised the highest price for years—£2l. Future Friday sales will be held at Newmarket. Greasy wool reached a record price for the season at the Melbourne sales on November 9, when 3u.id was paid tor Moorallah and Banongill merino.