Effect of Environment (Central Otago Wheats).
The effect of environment on strength of wheat is considerable. It has long been observed that comparatively high temperatures, long days, and absence of excessive moisture during ripening hasten maturation of the grain and increase its protein content; it was to be expected, therefore, that wheats grown in the drier districts of New Zealand would show differences from the average. Such has been the case with samples of wheats tested from Central Otago. In 1923 nine samples were received from the Tuapeka and Upper Taieri (Central Otago) districts, and all were found to possess very good strength. Some of these varieties were more or less unknown to wheat-growers, but amongst them were three samples of Velvet, all of which were prominent for strength in this collection of good wheats. Again in 1925 seven samples from Lake and Vincent Counties (Central Otago) produced loaves of very good volume. These particular flours, being low in protein content, were exceptions to the general rule that good strength is associated with good protein content; nevertheless, one of them (a sample of Tuscan) produced a loaf which compared favourably
with the best of the flours yet tested. The matter of low protein content and good loaf volume is referred to later (see “Degree of Buffering”).
In connection with the question of protein content it may be added that local samples of good strength have been compared with samples of wheat of accepted good strength grown in Kansas (the great wheat-growing centre in the United States) and have lost nothing in comparison (N.Z. Jour. Agric., 1923, vol. 27, p. 173).