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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

The use of sweet clover in a grain rotation as a means of increasing the fertility of grey-wooded soils.

Carder, A. C., 1910- January 1949 (has links)
The grey-wooded soils of Western Canada are becoming increasingly important due to the fact that future settlement will be largely confined to such soils. In the Peace River region today sizeable tracts of wooded soils are being brushed and broken for crop production by modern power machinery. Over the three Prairie Provinces grey-wooded soils consist well in excess of 100,000,000 acres and of the four major soil zones (brown, dark brown, black, grey-wooded) they represent by far the largest area. About two-thirds of the entire province of Alberta is made up of the grey soil zone. Vyatt (39) points out that ultimately over 50 per cent of all cropped land of this province will belong to the grey soil group. Of the surveyed area of the Peace River region 78 per cent or approximately 13,000,000 acres is of the grey-wooded or grey-transitional type. The grey-wooded soils are generally rather poor in fertility as they represent a degraded phase, the result of prolonged leaching under a forest cover. Under cultivation their scant organic matter rapidly disappears and the limited amount of available nitrogen is quickly absorbed by crop growth. Moreover, their initial poor physical condition is enhanced with puddling, washing, and blowing as the inevitable result. [...]
42

An evaluation of certain agronomic characteristics of tetraploid dollard red clover.

Mittelholzer, Alexander. S. January 1956 (has links)
Since the beginning of the twentieth century, plant breeders have been working with the aim of improving red clover. This plant Trifolium pratense L. belongs to the Leguminosae family and is one of the most important plants used as forage. Not only is it of consequence for animal nutrition, but it plays a valuable role in soil improvement by merit of the Rhizobium trifolii bacteria that live in nodular structures in the roots of this legume. Red clover is dependent on insects for pollination and is almost, if not entirely, crosspollinated and therefore exists in a heterozygous state.
43

Studies of Some Factors Affecting the Establishment of Certain Forage Species.

Anderson, Gordon Colin. January 1957 (has links)
Today in Canada there are approximately sixty-one million acres of land which are devoted to pastures and ranges, of which the greatest proportion is in a natural or unimproved condition, and therefore peak production is far from being realized. A fact that has been long known is that the sod crop represents the heart of a farm rotation. [...]
44

Influence of certain climatic factors on the varietal adaptation of oats.

Dermine, Pierre. January 1962 (has links)
The 1956 acreage of oats in the province of Quebec was estimated at a little over one million three hundred thousand acres, representing approximately eleven per cent of the total Canadian oat acreage. Thus, among field crops, oats come second only to hay crops for both the acreage covered and the total farm value of the produce. Oats are grown on a wide variety of soils and under a broad range of climatic conditions, from the warm summers of the Ottawa-Montreal plain to the shorter and colder seasons of Lake St. John and Northwestern Quebec. The importance of the crop brought up the need for varietal improvement through breeding and selection.
45

A study of certain factors affecting the adaptation of bird’s-foot trefoil (Lotus corniculatus L.).

Martineau, Real. January 1953 (has links)
It is a known fact that under the climatic conditions prevailing in Eastern Canada most pastures make poor growth during the drought period 0f midsummer, namely during July and August. Moreover there are large areas of sandy soils and up-lands that are too dry, too low in fertility or too acid to grow successfully the better know legumes such as alfalfa, red clover and Ladino. Alfalfa is a perennial plant, but it is confined to fertile and well-drained deep soils which have a pH 6.5 or higher.
46

Investigation of the nutrient status of corn with special reference to nitrogen and phosphorus.

Findlay, Wallace. I. January 1955 (has links)
Study of the nutritional status of crops as evidenced by plant analysis was begun as early as 1804. Recently efforts have been made by a number of workers to establish, by study of data on yields and the levels of different nutrients in specific plant parts, the response of these plants to applications of fertilizer. Further work has suggested the possibility of using the level of a leaf constituent at a specific physiological stage as a criterion of the state of supply of certain elements.
47

A proposed ‘growth cycle’ in red clover (Trifolium pretense, L.) to interpret morphogenetic aspects related to vegetative propagation, photoperiodism, and auxinology.

Cumming, Bruce. G. January 1956 (has links)
"Grasslands of the World are the largest undeveloped resources for increased agricultural production. More than half of the total land surface of the earth is in grazed lands. Most of these enormous acreages are unimproved. Improvement practices, based on research findings, can result in vast increases in production ……" This statement was made in 1952 in the "Foreword to the Proceedings of the Sixth International Grassland Congress."
48

The effect of chemical fertilizer treatment on culm diameter, crown development and plant height of three varieties of oats as related lodging.

Casserly, Leo. M. January 1954 (has links)
One of the most important cereal crops in Eastern Canada is oats. Lodging is one of the most serious hazards which limit the amount of chemical fertilizers that may be applied to this crop. There are more than one kinds of lodging. However the type of lodging which occurs prior to maturity is the most common. It involves a leaning or bending of the culms at ground level and often an uprooting of the immature oat plant. It is most frequently encountered after heavy rain or wind storms.
49

Predicting and Enhancing Spring Wheat Grain Protein Content Through Sensing and In-season Nitrogen Fertilization

Rellaford, Matthew John 09 June 2018 (has links)
<p> Grain protein content is an essential component to producing a profitable Hard Red Spring Wheat (HRSW) (<i>Triticum aestivum</i> L.) crop in the northern Great Plains. Growers can increase grain protein content through in-season N fertilization; however, the cost of these applications may outweigh the benefits. Predicting the grain protein content of early-season HRSW would give growers crucial information as they decide whether to apply in-season fertilizer to boost grain protein content. This research encompasses three studies; two of which aim to predict grain protein content with hand-held and aerial sensors respectively, and a third, which investigates the optimal rate, timing, and source of N fertilizer to boost grain protein content. Results of these experiments seemed to be greatly influenced by environmental factors. Findings of this research suggest that an in-season N application should be used for ameliorative purposes and not as a regular practice.</p><p>
50

Evaluation of Row Patterns for Mid-South Corn Production Systems

Poulsen, Tyson T. 29 August 2018 (has links)
<p> Row patterns affected irrigated corn productivity when grown in the Mid-South region of the United States. Narrow (76 cm) row spacing increased grain yield 8% when compared to traditional wide (96-102 cm) row spacing. Twin rows (20-25 cm spacing) in a wide (96-102 cm) row pattern, produced similar grain yield as a traditional wide single row. At a normal plant density of 79,040 ha<sup> -1</sup>, traditional wide rows yielded 10.51 Mg ha<sup>-1</sup>, twin wide rows yielded 10.34 Mg ha<sup>-1</sup>, and the narrow rows yielded 11.33 Mg ha<sup>-1</sup>. Growing corn at various plant densities did not affect corn grain yield response to various row patterns. As a comparison the traditional wide rows and twin rows were similar in their yield, and the narrow rows performed better. Corn grain yields for the traditional 96-102 cm wide single rows were 11.20 Mg ha<sup>-1</sup>, wide 96-102 cm twin rows yielded 11.22 Mg ha<sup>-1</sup>, and narrow 76 cm rows produced 12.07 Mg ha<sup>-1</sup>. Row pattern had no effect on corn plant height, photosynthetically active radiation (PAR), leaf area index (LAI), SPAD, stalk diameter, and plant lodging in either study.</p><p>

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