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Browsing Theses by Author "Acharya, Surya"
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- ItemThe agronomic benefit of pulp mill boiler wood ash(Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2001, 2001) Patterson, Shane; University of Lethbridge. Faculty of Arts and Science; Thomas, James E.; Acharya, SuryaLand application of wood ash is becoming more appealing, as a disposable alternative, to landfilling options. It is estimated that 110,000 tonnes of wood ash is produced annually in Alberta by cogeneration systems, a large percentage produced in Central and Peace River Regions of Alberta. Alkaline (pH-13) properties and nutrient content of wood ash provides an alternative for the acidic and nutrient deficient soils within these regions. The objective of this field study was to determine the effect wood ash applications would have under field conditions on: the chemical and physical properties of soils; barley dry matter production; grain and seed yield of barley and canola; and the nutrient and metal uptake by crop tissue. Ash applications significantly increased dry matter and seed yield, improved crop nutrient quality, increased soil pH and improved soil nutrient availability, while not infringing on any environmental regulations.
- ItemCharacterization of new sainfoin populations for mixed alfalfa pastures in western Canada(2014-05-13) Sottie, Edmund Tei; Thomas, James E.; Acharya, SuryaA series of experiments were conducted to compare nine new sainfoin populations developed to persist in mixtures with alfalfa under a multiple-cut management. In trials at Lethbridge under rain-fed and irrigated conditions, new sainfoin populations produced higher (P<0.05) dry matter yields as compared to Nova sainfoin. New cultivars persisted for three production years in mixed stands with alfalfa accounting for >20% DM at each harvest. Condensed tannin concentrations in sainfoin were highest at the bud stage. One new sainfoin population, LRC-3519 seeded in alternate rows with alfalfa caused a reduction (p<0.001) in bloat incidence by 98% as compared to Nova-alfalfa stands. Average daily gains (>1.0 kg d-1) of steers on alfalfa-sainfoin mixed pastures were similar (p>0.05). Seeding of these new sainfoin populations in mixed stands with alfalfa could prove to be a means of taking advantage of the productivity of mixed forage legume pastures while preventing bloat in grazing ruminants.
- ItemDetermination of water use efficiency for forage legumes in Southern Alberta with emphasis on dryland and irrigated alfalfa cultivars(Lethbridge, Alta. : University of Lethbridge, Dept. of Biological Sciences, 2014) Attram, Jeremiah; Thomas, James E.; Acharya, SuryaField studies were conducted at Lethbridge and Picture Butte in 2012 and 2013 to determine the effects of irrigation water application levels on the dry matter yield, water use efficiency (WUE) and forage quality of irrigated and dryland type alfalfa cultivars. These studies indicated that: 1) Alfalfa cultivars developed for irrigated areas could be irrigated at 75% of the volume applied to the optimal treatment, with 40% depletion of available water at the root zone without incurring drastic yield loss; 2) Both the irrigated and dryland alfalfa cultivars can be irrigated at 75% of the volume of water applied to the optimal treatment, with 40% depletion of available water within 60 - 90% of the root zone with a greater prospect of optimizing WUE of these cultivars under southern Alberta growing conditions; and 3) The height of alfalfa and stage of maturity at the time of harvest affects alfalfa nutritional quality.
- ItemDevelopment of disease resistant fenugreek for Western Canada.(Lethbridge, Alta. : Universtiy of Lethbridge, Department of Biological Sciences, 2018) Subedi, Udaya; University of Lethbridge. Faculty of Arts and Science; Thomas, James E.; Acharya, SuryaCercospora leaf spot (CLS) caused by Cercospora traversiana is an important phyto-pathological problem of fenugreek (Trigonella foenum graecum), a multiuse legume crop. Knowledge about the inheritance of genes controlling CLS resistance is essential when selecting suitable breeding approaches while information about epidemiological factors affecting the disease can help develop new control strategies. Our greenhouse and field experiments showed CLS resistance in fenugreek (L3717 and PI138687) to be governed by a single dominant gene which is moderately heritable (46% narrow sense heritability). This indicates a relatively simple pathway for transfer of genes to adapted fenugreek cultivars. Rapid screening techniques (detached leaf assay and whole plant assay) were developed to identify the degree of resistance to C. traversiana in fenugreek genotypes. Several epidemiological factors such as temperature, physical injury (wounding), level of host resistance, plant age and inoculum concentration were found influencing CLS severity in controlled environment conditions.
- ItemIdentification of high seed yielding and stable fenugreek mutants(Lethbridge, Alta. : University of Lethbridge, Dept. of Biological Sciences, c2011, 2011) Prasad, Rajib; Acharya, Surya; Thomas, James E.Fenugreek (Trigonella foenum-graecum L.) was recently introduced to western Canada as a forage crop. To reach its full potential, high yielding, early maturing fenugreek cultivars that produce good seed yield and quality within 100 frost free days need to be developed. In this study, mutation breeding approach was used on five locally adapted fenugreek genotypes to generate variants showing improved seed yield and yield attributing traits that can be used for cultivar development. Mutant generations of these plants were evaluated in multi-location, multi-year trials, and individual plants were selected for high seed and biomass yield. Seeds from a tetraploid fenugreek line and its diploid parent Tristar were grown under multiple environments to understand effect of environment on seed oil content. In addition, mold resistant fenugreek genotypes were identified by screening a collection of fenugreek accessions against a destructive fungal pathogen Cercospora traversiana.
- ItemRejuvenation of depleted pasture using bloat-free legumes for high performance cattle grazing(Lethbridge, Alta. : University of Lethbridge, Dept. of Biological Sciences, 2018) Khatiwada, Bikash; Thomas, James E.; Acharya, SuryaDirect seeding into existing pasture is expected to reduce time for rejuvenation and loss of productivity. To accomplish this, experiments were conducted to determine appropriate method of pasture rejuvenation using bloat-free forage legumes. Four sainfoin (Onobrychis viciifolia Scop.) and three cicer milkvetch (CMV) (Astragalus cicer L.) populations were seeded into alfalfa and grass pastures using three seeding methods to compare their ability to establish and persist in the mixtures. At Lethbridge where the old pasture was predominantly alfalfa, significantly higher (p<0.001) proportion of newly established plants were observed when the pasture was completely plowed and reseeded with both alfalfa and test populations (cultivation method) than directly seeding sainfoin or CMV for rejuvenation. Between the two test populations sainfoin contributed higher (p<0.05) proportions of plants to the pasture mix compared to the CMV populations. Two of the three new sainfoin populations, AAC Mountainview and LRC3432 seeded in alternate rows with alfalfa contributed >20% (p< 0.05) in total dry matter (DM) yield at each harvest. In grass pastures at Ponoka and Red Deer maximum biomass contribution from test populations when drilled were 2.3% and 8.2% respectively. Grass-legume mixtures with >10% legume stands increased soil available nitrogen in 2 years. Although in two years sainfoin and CMV mixed pastures did not sequester organic carbon in soil, they increased microbial carbon biomass and enzyme associated with C-cycling. Seeding of two sainfoin populations AAC Mountainview and LRC3432 into established alfalfa pasture could improve productivity of existing pasture while preventing bloat in grazing cattle.
- ItemSeed production technology for fenugreek (Trigonella foenum-graecum L.) in the Canadian prairies(Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2006, 2006) Basu, Saikat Kumar; University of Lethbridge. Faculty of Arts and Science; Thomas, James E.; Acharya, SuryaFenugreek (Trigonella foenum-graecum L.) is an annual legume mainly used as a spice crop in many parts of the world. "Tristar" is a new forage cultivar that requires - 120 days to produce mature seed in western Canada where only - 100 frost-free days are available. The goal for this study was to reduce maturity duration for the crop through a series of studies on the genetics and agronomic aspects of fenugreek. This two year study suggests that: 1)mutation breeding using Tristar seed as a base population could be successfull; 2)multi-location trials using world accessions exhibited genotype X environment interaction; 3)swathing of plants before freezing temperatures set in; 4)application of phosphate fertilizer increased seed yield and; 5)foliar sprays of chemicals can be used for production of high quality seed. In this study some short duration, high yielding and determine lines of fenugreek were produced improving the potential for use of fenugreek and the economics of beef production in western Canada.