SHRIVELLED GRAIN.

Otago Witness, Issue 3292, 18 April 1917, Page 13

SHRIVELLED GRAIN.

The fact that seed wheat is none too plentiful or is firmly held may tempt growers who elect to sow this autumn to rest content with an inferior sample of seed to their lasting regret. This matter of quality in seed was of some concern two years ago in Australia, and the question whether it was wise to sow shrivelled grain with any degreo of safety was carefully considered in the light that it might jeopardise the quality of the following Season's grain. Professor Perkins, of South Australia, had the following to say in this connection: "In considering the matter we should recollect that any .organised being—and seed is as much an organised being as a human—comes under two influences — namely, inheritance, which is fundamental and fixed, and environment, which is accidental and variable. You have your grain of oats, therefore, the result partly of inherited tendencies and partly of surrounding conditions. The first question, then, is, ' What are the inherited tendencies present in every oat grain, whether it is shrivelled or well developed? The answer is that they include all cultural characteristics of the variety, bred into it through _ a long succession of generations. You will get the same character of straw, the same oolour of grain, and the same size of grain, etc.

"It is as well to bear in mind that in so far as these characteristics are concerned, the influence of a single season is practically nil. This means • that, given favourable conditions in the present season, all the inherited characteristics should reappear in the new plants, whatever the character of the grain may be. This would seem to imply that shrivelled, ill-developed grain is quite as good for seed as large, plump grain. However, neither general experience nor direct experimental work in the subject confirms this view. Dr Cobb, in New South Wales, conducted very careful experiments for over three years, and his final conclusions were very definitely in favour of the plump, well-grown grain. The fact is that we have yet to consider the influence of environment or surrounding conditions on the final development of the young plant. " We can summarise the influence_ of environment under the following headings: (1) The start in life of the plant; (2) the ability of the plant to feed_ itself adequately; and (3) weather conditions throughout the period of growth. Now, we can rule out the last two points, because thgy would operate equally whether the grain was well or badly developed. There remains, then, for consideration the first point—the start in life of the young plant. This may conveniently be divided into two sections under the subheads (1) germination and (2) early development. " Germination itself may be said to_ depend on the' (1) vitality and healthiness of the germ attached to the grain, and (2) in suitable conditions of soil, of moisture, and of temperature. As the latter operates equally in all cases, the only point we need consider is the vitality and healthiness of the germ. Here, I am afraid, everything is in favour of the plump, welldeveloped grain. If you take 100 sound, plump grains, and sow them under favourable conditions, they should all germinate. The same is not the case with shrivelled, ill-developed grains, as a proportion, ' more or less great according to the circumstances, will fail; henoe the necessity with poor grain for sowing a greater number of grains to the acre —not necessarily a greater weight, as they are lighter. "Lastly, we have the early development of the. young plant, and here, again, the ill-developed grain is at a disadvantage. The weight of the germ which ultimately develops into the oat plant is very incon siderable—probably not 1 per cent, of the grain-. One-quarter of its weight is_ represented by husk, and the balance food upon which the young germinating seedling draws in its early stages. This food is vei'y largely in the form of starch. The germinat : on process gradually liquifies it, and in th ; s state it passes into the tissues that are being formed in the young plant. It is here that the ill-developed gram is at the greatest disadvantage. In this grain the amount of starch stored up for theyoung plant is never equal to that in plump grain, and the young plant suffers in the same way as a calf that is stinted of milk. It may -ecover in time, particularly in good, rich soil and _ in a favourable Beason. Generally speaking, however, the start will influence final growth and yield; but it can have no influence on the plumpness or general development of the grain. "To summarise these points: Plants produced from defective grain will germinate less freely and start off less well than those from good, plump grain. Yields of hay and grain will . probably be lighter • but, given good conditions, there is nothing to Interfere with the quality. The latter is exclusively a factor of surrounding conditions."