MATURITY OF WHEAT

Ashburton Guardian, Volume 52, Issue 206, 13 June 1932, Page 7

MATURITY OF WHEAT

EFFECT ON ANNUAL YIELD. MILLING AND BAKING QUALITIES Following up a previous report on experiments in connection with the maturity of wheat for cutting, the second annual report of the Wheat Research Institute, which has just been published, contains further interesting information on this subject. The previous report gave a definite stage of maturity for cutting wheat to secure the highest yield without risk of loss from shrivelling or shaking. It also gave the result of two years pf trials on the milling extraction of wheats cut on the green side, at the binder-ripe stage, and when fully ripe. Then it was shown that under careful sampling the average milling extraction of three varieties was: Cut before binder-ripe, 67.5 per cent - J cut after binder-ripe, 69.2 per cent. ' The trial was repeated in 1931, under very careful sampling conditions. Only one crop was used—one of Tuscan growing at Lincoln College. Twentyone plots 30 feet long and consisting of two rows each were laid down in triplicate. The three plots called ono made up the first milling sample, the three plots called two the second milling sample, and so on. The first plot was cut when the crop was considered about 10 days off the binder-ripe stage, and a plot was cut every second day thereafter. The main crop was cut on January 29 and from then on each second , day saw the cutting of _ two samples, one with long straw as if cut with a binder, and with short straw as if cut with a header. All the longstrawed sheaves were stooked, and the short-strawed heads were hung in openwork bags on a wire fence. All the samples were threshed on the same day. Careful notes were taken ef weather conditions. The following table gives the milling extraction figures:—

"There is here some evidence that milling extraction tends to decrease if wheat is cut after a definite stage of maturity," states the report, but since the average of four cuttings before binder-ripe was 74.4 per cent., and the average of four cuttings after was 73.8 per cent., the difference probably does not mean anything, being within the limits of the probable error in the work of the experimental mill. The trial is being repeated this year. Baking Scores. "The flour secured from these milling tests was aged ■ for about eight weeks, and baked as each became eight weeks old, a constant fraction of each flour being used for the baking test. The scores were as follow: —

"This is a remarkable result. It shows that the baking quality improves steadily until the binder-ripe stage is reached, and then suddenly and markedly improves for the next week after which the improvement ceases. It the figures can be relief on to represent general conditions they mean that the baking quality of the wheat would be greatly improved by leaving the wheat to stand for several days after the stage at which it is at precent cut It has in the past been the general advice to cut on the green side, and these figures show that in this case, at any rate, early cutting has caused an arrest of the development of the qualities that make for good baking quality. ■ Results Tentative. "One fact that wheat cut on the green side tends to be clear in colour. Another fact is that the best milling ■and baking wheats in the world are clear in colour. It was therefore argued that if early cutting secured clear colour that it would also secure high baking quality, and hence this general advice. But there are possibly different causes that produce the same effect of clear colour. If it is produced by climatic conditions, soil, variety, as it is in Canada, then clear colour means good baking quality; if it is produced by early cutting, then it does not produce a good baking quality, but a poor one instead. "These results are, of course, only tentative so far, and are not intended to be used as a guide to practice. It has been suggested, for instance, that the fall of 86 points of rain on January 28, just before the great rise in quality started, was the cause of the improvement, and that without the rain the mere delay in cutting would have had no effect. The trial is being repeated during the harvest of 1932, using three fields at different stages of maturity. Another point brought out by the

figures is that cutting with, the straw long, as is the case with the hinder, allows a transference of foodstuffs from the straw to the grain that improves baking quality. The baking score for wheat with long straw is always higher than that cut with short straw.”

Milling Date of Cutting, Extraction and how cut. Per cent. January 10, long ... ... 69.2 January 12, long ... ... 70.7 January 14, long .., 71.8 January 16, long ... ... 73.8 January 18, long ... . ... 74.3 January 20, long ... 75.6 January" 22, long ... 75.0 January 24, long ... 74.9 January 26, long ... 73.9 January 29, long ... 73.9 January 29, short .. 74.0 January 31, long ... ... 73.6 January 31, short .. 73.7 February 2, long ... 73.9 February 2, short .. ... 74.3 February 4, long ... 72.5 February 4, short .. 73.1 February 6, long ... 72.3 February 6, short. .. 72.3 February 8, long ... 71.9 February 8, short .. 72.2

Date of Cutting, Balnn , and how cut. Score. Januaiy 10, long ... 20.5 January 12, • long ... 24.5' January 14, long- ... 24.5 January 16, long ... 25.5 January 18, long ... 23.5 January 20, long ... 23.0 January 22, long ... 25.5 January 24, long ... 28:0 January 26, long ... 26.0. January 29, long ... 29.0 January 29, short ... 27.5 January 31, long ... 32.5 Januaiy 31, short ... 29.0 February 2, long ... 33.5 February 2, short ... 36.0 February 4, long ... .39.5 February 4, short ... 38.0 February 6, long ... 38.0 February 6, short. ... 38.0 February 8, long ... 39.5 February 8, short ... 38.5