WHEAT DAMAGED BY BUG

Press, Volume LXXXVI, Issue 26032, 8 February 1950, Page 4

WHEAT DAMAGED BY BUG

BAKING QUALITIES AFFECTED SOME LINES REJECTED FOB FLOUR-MAKING As a result of damage by so-edited wheat bugs, some lines of current wheat ‘crop have been rejected for milling and baking. This W reported yesterday by Mr E. W. Hullett. chief chemist at the Wheat Research Institute, Christchurch, who explained that the damaged wheat was unsuitable for the manufacture of flour because the dough became sticky and soft during fermentation and the crumb of the bread was very coarse. As far back as 1936 attention w drawn to the fact that certain liW wheat from Otago produced , ‘sticky dough” or “slimy gluten” during fermentation, said Mr Hullett, but it was not until the current season that the damage had assumed considerable proportions. . The damage was fortunately nottcea early in the present season. The dam* aged samples were among the first eight wheat samples to be tested at the Wheat Research Institute, and a warning was immediately sent out by the institute to all flour millers and grain merchants. They have accordingly been able to guard against tpe impairing of flour quality by the use of damaged wheat. T , The incidence of the damage has also declined as the season has advanced. At the beginning of the season about one in four lines tested at the institute was affected, but the incidence has become much less. A large number ot samples, sent in by millers, have been tested by the institute for damage by the bugs. Suitable for Seed Experiments made some years ago by the late Dr. F. W. Hflgendorf. former director of the Wheat Research Institute, showed that the grains attacked germinated normally, so that lines rejected by millers for milling are perfectly suitable for seed. They are also suitable for feed for Poultry and other animals. It is not considered that there will be any difficulty this season in disposing of all the affected wheat for seed or feed. “Sticky gluten” wheat caused a serious problem in Europe between 19Z» and 1933, and it was not till 1931 iha» it was linked with the attacks of insects. This was first reported by c. Bawmann, a Spaniard. .. After two hot and dry summers lv was noticed in Germany in 1935 tnai the insects that did the damage baa greatly increased, and it is now thought that the highest incidence oi damage follows such conditions. Mr H. E. West, formerly of the Wheat Research Institute, and now head of the William Angliss Fora Trade School in Melbourne, was tne first to draw attention to slimy gluten” wheat in New Zealand in w® It was decided that a thorough investigation of the problem should be unae£ taken to find out whether the msects responsible for the damage to wneav in the Northern Hemisnhere naa gained entrance to New Zealand, or whether there were other insects present in the country which were cap" able of damaging wheat in a similar manner. . . j An intensive survey of the inftjw districts in Otago was made in I?*? "J Mr M. L. Morrison, entomologist Canterbury Agricultural College, a series of experiments were made Or screened wheat plots at Lincoln, using a variety of insects collected frjj crops growing in Otago. It was show? that the insects responsible for trouble in other countries were W present in New Zealand, but that.« least three different species of bug (hemiptera-heteroptera) occurtog in New Zealand were capable of J* tacking the grains and producing “sticky dough. They are StenOWJ binotatus, Nysius huttoni, and anceps. T Several of the Wheat Research stitute’s experimental wheat trial plow at Lincoln have been attacked by JJ? bug, and for quality trials they wou l be useless, said Mr Hullett.