• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 546
  • 246
  • 119
  • 113
  • 113
  • 113
  • 113
  • 113
  • 113
  • 37
  • 19
  • 18
  • 5
  • 4
  • 2
  • Tagged with
  • 2030
  • 499
  • 476
  • 458
  • 374
  • 231
  • 196
  • 192
  • 181
  • 179
  • 157
  • 147
  • 127
  • 100
  • 94
  • 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.
11

The influence of certain environment factors, particularly soil types, on the sward cover of permanent pastures in selected areas of the St. Lawrence Lowland, Eastern Podzol, and Laurentian Upland regions of Quebec.

Knutti, Hans. J. January 1962 (has links)
Pastures constitute an integral part of the acreage on most farms in the humid North-East or North America. In the Province of Quebec one firth of the farmland is devoted to pastures of one soil or another, representing three and three quarter million acres. Although adequate grassland resources are evidently of primary importance in grassland farming, pasture improvement progresses slowly, for mainly two reasons, firstly, the pastures are usually the most neglected crop on the average farm, and secondly, an entire misconception or the nature of grassland, i.e. the non-recognition of its complex nature.
12

Effects of mineral nutrition and certain other environmental factors on loose smut development in barley.

Lukosevicius, Petras. P. January 1962 (has links)
Loose smut of barley caused by Ustilago nuda (Jens.) Rostr. is a disease that becomes evident mainly after heading of the host. The spikes of infected plants emerge from the boot slightly earlier than those of healthy Plants. Powdery masses of spores are formed in place of kernels. These masses of spores are covered at first with a membrane, which ruptures early to expose the dark brown chlamydospores. Under certain conditions, sori may form in the upper leaves mostly in the nag leaf. These sori appear five to ten days before heading. The chlamydospores are dislodged from the smutted heads by air currents at the time healthy plants are in flower, leaving bare rachises.
13

The influence of environmental conditions upon alfalfa growth in the Yukon.

Tsukamoto, Yoshikazu. January 1962 (has links)
The future development of the natural resources of the Canadian North definitely includes agriculture and agriculture in that area is not a novelty but a reality, as stated by Nowosad (1959). The importance of agriculture and its possible development in the Yukon Territory was discussed in the debate of the House of Commons by Nielson (1960). The soil survey in the Yukon, conducted by Day in 1957-58 reveals that the soil in general is low in organic matter, nitrogen and phosphorus. Marked advantages resulted from application of manure and commercial fertilizers on grain crops and favorable results were also obtained by the application of nitrogen fertilizer on pasture crops as reported by the Whitehorse Experimental Farm (1958).
14

A study of interspecific competition with particular reference to its determination using a point quadrat method.

Hargreaves, George. January 1963 (has links)
Steppler, H.Competition was studied between four forage species grown alone and in all possible combinations. By the use or a wire grid of 2"x 2" squares, species in the mixtures occupied a predetermined pattern of arrangement. According to yield and leaf area, bromegrass was the most competitive and birdsfoot trefoil the least competitive species. Timothy and Ladino clover varied in competitive ability throughout the season. The yield produced par point density of each species was determined by a point quadrat method. Comparisons were made between mixtures and pure stands to see if this value was affected by and thus could be used as a measure or competition.
15

Studies on the Mesostigmata and Trombidiformes (Acarina) of two Quebec woodland humus forms.

Marshall, Valin. G. January 1963 (has links)
The present investigation in Soil Zoology was initiated in 1960 at Macdonald College, McGill University. The problems relative to the study of the soil fauna are complex, requiring at the very outset, not only familiarity with the soil itself but also some knowledge of the many diverse groups of animals encountered. The aid of specialists for the difficult task of identifying the animals normally round in the soil, also, is almost indispensable (Alvarado and Selga, 1962). The project here discussed is limited to the study of two suborders of Acarina, the Mesostigmata and Trombidiformes of two Quebec woodland humus forms.
16

Yield responses of oats to fertilizer nitrogen as influenced by certain nitrogen fractions in selected Quebec soils.

Elwin, John. H. January 1964 (has links)
Soil nitrogen is important from an agronomic viewpoint, because nitrogen is essential in the synthesis of complex organic substances such as proteins, which are an important source of food for man and feed for animals. The total nitrogen present in most soils is relatively small, and is constantly undergoing many transformations, both chemical and microbiological. However, only a significantly small fraction of the total soil nitrogen is in a form that is available to plants. The ease with which available inorganic nitrogen compounds may be lost from the soil through leaching, erosion and crop removal is an indication of the importance of the study of nitrogen in soils.
17

The influence of immaturity and seed source on the subsequent performance Zea Mays L.

Faust, Noel. J. January 1964 (has links)
Seed production areas and seed consuming areas rarely coincide in this era of scientific agriculture and efficient transportation. That it is not necessary for the two to coincide is based on the premise that the performance of a plant is directly associated with its own genotype and not on conditions under which the seed was produced. McFadden (1963) has cast serious doubt on the validity of this premise with the discovery that the same variety of barley would produce different yields in the same yield trial if the seed were grown in different geographical locations. He found, for instance, that the variety Montcalm grown from seed produced at Guelph (Ontario) gave a higher yield than Montcalm grown from seed produced at Beaverlodge (Alberta), when planted the following year at Guelph (Ontario), Brandon (Manitoba), Lethbridge and Lacombe (Alberta). According to McFadden (1963), it would appear logical to select potentially suitable locations as seed increase centers.
18

The yield, botanical composition and quality of forage as influenced by chemical fertilizers.

Hew, Ewan. G. January 1964 (has links)
In a report presented by Frens (1955) it was pointed out that, apart from some exceptional cases, an extension of the present grassland area could not be advocated in a great number of countries. Consequently, efforts will have to be concentrated on intensifying the production of the existing grassland area or improving the quality of grass. It was stressed that at the same time the best possible management practices would be required. On the basis of the 1951 census, Raymond (1958) in a bulletin on pastures for Quebec showed improved pastures in the province as having a carrying capacity of 1.6 acres per animal unit whereas when the total area - 4,768,313 acres - is considered, a carrying capacity of almost exactly 3 acres per animal unit is obtained.
19

The response of oat crops and succeeding hay crops to chemical fertilizers on different soil types in southwestern Quebec.

Beauchamp, Eric. G. January 1962 (has links)
In a recent publication* by the Quebec Fertilizer Board for farmers, some emphasis was placed on the fact that the soils of Quebec are "undernourished" and are gradually becoming "impoverished." Figures were also presented which indicated that there was a general decline in fertilizer usage during the 1945-1956 period. It has been the general opinion that the soils of Quebec are not sufficiently fertile to warrant this decline in the use of commercial fertilizers. To study the situation more thoroughly, the establishment of field experiments appeared to be a logical endeavour.
20

The yield and quality of selected improved and unimproved pastures in Quebec in response to differential fertilization.

Warnaars, B. C. January 1966 (has links)
Nitrogen, phosphorus and potassium fertilizers at three levels were applied in all possible combinations annually to two improved and four unimproved pastures in Quebec. Botanical composition, crude protein, phosphorus, potassium and a Nutritive Value Index (N. V .I.) were determined on broad and narrow leaved grasses, legumes and others. [...]

Page generated in 0.0255 seconds