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The use of heterosis in the production of agricultural and horticultural crops | Heterosis in the production of agricultural and horticultural crops
1949
Ashton, T.
Changes in American farming | Changes in farming in war and peace
1949
Johnson, Sherman Ellsworth
This report is a revision of the summary of a study that was begun in the fall of 1944 with the same purpose of analyzing the changes in farming during the interwar and war years, appraising the forces back of the large increases in production, and evaluating some of their peacetime implications. The background data used for this analysis are largely the statistics contained in the crop and livestock reports and other production releases of the Bureau of Agricultural Economics. | This study was undertaken in the belief that a first requisite for intelligent action on our peacetime production problems is an understanding of the nature and strength f the forces that have shaped the course of agricultural production in the years to come.
Показать больше [+] Меньше [-]Grass seed production: Potentially profitable crop suitable for place in crop rotation system
1949
D Sumner | M Miller
The following article is an abstract from a forthcoming Agricultural Extension Circular on Grass Seed Production now in preparation by the same authors.
Показать больше [+] Меньше [-]Un breve estudio sobre las mastitis bovina
1949
Castruita López, José | Rodríguez Dávila, Roberto
"Todos los pueblos de la tierra se nutren con alimentos que ellos mismos producen o que importan de otros países unos pueblos comen carne de mamíferos, otros principalmente de peces y mariscos"
Показать больше [+] Меньше [-]La explotación del cerdo en el Norte de Coahuila.
1949
De la Garza Villareal, Félix
"La exportación del cerdo es una industria pecuaria es una importancia económica, tanto por que produce materias alimenticias de consumo universal"
Показать больше [+] Меньше [-]algunas consideraciones sobre los trabajos de conservación del suelo y el agua
1949
Mendoza Medina, Santiago | Pacheco Badillo, Pedro | Siller Siller, Demetrio
"Unos de los problemas más graves que aquejan a nuestra patria y en general a todo el mundo es sin duda es la paulatina perdida de la principal fuente de riqueza"
Показать больше [+] Меньше [-]Annual Report of the Game Department for the year ended 31st December, 1947
1949
Game Department, Uganda Protectorate
) General (2) Legislation (3) Nets (4) Imports and Exports of Dried Fish (B) Economic:-(I) Lake Victoria (2) Lake Albert (including the Albert Nile(3) Lake Edward and Associated Fisheries (4) Lake Kyoga (5) Minor Lakes, Dams and the Victoria Nile (6) Introductions (7) Fish Transfers (8) Crocodiles:-(C) AnglingTrout Nile Perch BarbelTilapia Variabilis
Показать больше [+] Меньше [-]East African Inland Fisheries Research Organization Annual Report for the year 1948
1949
East African Inland Fisheries Research Organization
IntroductionThe laboratory at Jinja is being developed as a centre forhydro-biological research in East Africa, It has been built and is at present wholly financed from a grant from the Central Research allocation of the Colonial Development Fund. The building contains six laboratories in addition to a library, common room and general office. A maximumnumber of ten research workers could be given laboratory accommodation. However, shortage of living accommodation will limit the numbers who can work here for the next year or two. | Library stamp on first page has: EAFFRO Occasional Paper, 3.
Показать больше [+] Меньше [-]A study of speckled leaf blotch of wheat and its causal organism (Septoria tritici Rob.), in Canterbury, New Zealand
1949
Wenham, Hugh Trevor
An error in production has resulted in there being no page numbered p66, however no text is missing. | The available evidence suggests that speckled leaf blotch of wheat is increasing in severity in Canterbury. Prior to 1947 it was practically unknown in the province, but in November of that year a wheat crop at Lincoln College was found to have a high percentage infection. In November of 1948 a preliminary survey of wheat crops in North Canterbury was made by the writer, and of forty fields inspected, all except two were found to be infected. This evidence, together with the known potential importance of the disease as illustrated by the severity of attacks in overseas countries has emphasised the need for fundamental studies of the disease and its causal organism under New Zealand conditions. This thesis embodies the results of a two year study conducted at Canterbury Agricultural College, Lincoln, during 1948-49 and is intended to contribute to our understanding of the disease. The aims were 1. To isolate and prove pathogenicity of Septoria tritici Rob. as causal organism of speckled leaf blotch under Canterbury conditions. 2. To study signs and symptoms as they occur in the field and under glasshouse conditions. 3. To study the causal organism in pure culture. 4. To study host range of the causal organism in New Zealand. 5. To study varietal resistance to the disease in New Zealand wheats. 6. To determine the mode of perpetuation of the causal organism in New Zealand.
Показать больше [+] Меньше [-]Safflower production in the western part of the northern great plains
1949
Claassen, Carl Ernest