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The experiment on wheat seeding depth in CanadaСодержание книги
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Wheat is generally sown only deep enough to place the seed in moist soil that will be adequate for normal germination of the seed and growth of the young plant. In humid climates most of the wheat is sown at depths of 2.5 to 7.6 cm. In dry climates it is often necessary to sow at depths of 5.0 to 10.2 cm in order to place the seed in moist soil. Some producers believe that varieties of spring wheat differ in their response to seeding depth. In order to investigate this problem, a study was started in1970 at the Research Station, Swift Current in Canada. Three varieties of spring wheat, Manitou, Thatcher and Chinook, were sown on loam soil at depths of 2.5, 5.1, 7.6 and 10.2 cm. Seeding was done with one-row hand-operated seeder. Plots consisted of four rows with 22.9 cm between rows and 5.0 m in length. Over the 4-year period the three varieties were compared at the four seeding depths on the basis of a number of plants and number of heads1 per 3 m row and the yield. The data clearly demonstrate that the 5.1-cm depth of planting for all three varieties was better than either the shallow depth of 2.5 cm or the deep planting of 10.2 cm in the number of mature plants, and the final yield. The experiments show that at the depths less than 3.8 cm the soil is often too dry for good germination and stands2 may be reduced. Notes and Commentary 1 head – колос 2 stands- сходи
NEW HYBRID WHEATS IN AUSTRALIAN FIELDS Hybrid wheat is already a commercial reality for farmers throughout the wheatlands of America. Australia is going to conduct the first production trials1 of hybrid wheats on the fields of its best farmers. Hybrid wheats are more resistant to rust2 and other cereal diseases than the present ordinary varieties and their milling and baking3 qualities are among the best of the present-day wheats. As with other grains the yield potential of the hybrid varieties is as much as 20 to 25 per cent above what can be expected from non-hybrid varieties. However, there are some drawbacks4 in growing hybrid wheats. They are:1) hybrid wheat used for seed costs considerably more than ordinary wheat seed and many farmers will think hard before growing only hybrid wheats; 2) the hybrids will produce high expected yield only if they have adequate moisture during the growing season; in other words, under irrigation the hybrid weats can be expected to give a great increase in yield but in normal dry farming they will be at greater risk than ordinary wheats; 3) farmers that grow hybrid wheats will have to buy new seed from the hybrid breeders each year as crops from their own grown seed will quickly produce lower yields.These drawbacks may limit the growing of hybrid wheats by Australian farmers. It is interesting to note that, while all 10 hybrids released so far in America are hard red winter wheats, the Australian program has been directed to the development of white wheats, for which Australia is famous in world markets. Notes and Commentary 1 trial - дослід 2 rust - іржа 3 milling and baking – борошняні та пекарські 4 drawback – недолік CORN Most of corn grown at present is known as hybrid corn. Due to the development of hybrid corn better quality grain and higher yields nave been obtained. Now some new types of corn and some new methods of growing corn are being developed and discussed by the scientists all over the world. HIGH-LYSINE CORN Why is high-lysine corn valuable?. The experiment on feeding high-lysine corn to young pigs was conducted in the United States. They grew twice as fast as the pigs fed with common corn. Some young pigs were fed with only common corn. These animals developed a protein-deficiency disease and after 110 days they began to die. High-lysine corn is also very important in the diet of people. The scientists believe that new high-quality protein corn will be commercially produced throughout the world. "WAXY"1 CORN What element makes corn waxy? Waxy corn is another type of corn developed to increase its feeding qualities. It is called "waxy" because its starch2 is like wax. Corn starch is the source of most of the energy in the grain. About 25 per cent of starch is usually amylase, the element that is not digested by animals. The other 75 per cent is amylopectin that is highly digestible. It is due to amylopectin that corn is such an important high-energy feed. The scientists are working now to develop corn with 100-per cent amylopectin-type starch. Notes and Commentary 1 waxy - восковидний 2 starch - крохмаль
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