The experimental work reported in this thesis quantified the productivity of lucerne over a two-year period (2000-2001) for a Mediterranean climate at Roseworthy in South Australia (34°32′S, 138°45′E), and determined associated dynamics for water and nitrogen in duplex soil. Shoot growth of dryland lucerne was limited primarily by the pattern and amount of incident rainfall, but high temperature (30-35oC) also constrained summer production. These high summer temperatures induced greater production when irrigation was applied, but under the normally dry summer conditions high temperatures combined with soil water deficit (up to 200mm) caused growth to cease. Thus, shoot dry matter yield under rainfed conditions was 4.9 t ha⁻¹ in 2000 (from 7 harvests) and 1.8 t ha⁻¹ in 2001 (from 5 harvests) whereas summer irrigation increased yield to 14.9 t ha⁻¹ in 2000 (7 harvests) and 7.1 t ha⁻¹ in 2001 (5 harvests). Under rainfed conditions the RUE was 0.55 g DM MJ⁻¹ PARi compared with 1.08 g DM MJ⁻¹ PARi in the irrigated treatment in 2000, reducing to 0.4 g DM MJ⁻¹ for the rainfed and 0.7 g DM MJ⁻¹ under limited irrigation in 2001. Lucerne plant population declined from 69 to 20 (plants m⁻²) in the rainfed treatment and the plants partially compensated for this in 2000 by increasing stem density from 300 to 400 m⁻² in 2000 although this declined back to 300 m⁻² in 2001. In all treatments more than 70% of root biomass was in the top 40 cm soil, this was partially due to the vertical distribution of plant available water but also to subsoil constraints to root development below 0.6m. Nevertheless, lucerne was able to extract water and nitrate to 1800 mm soil depth. Large amounts of irrigation >400mm) over summer (Dec 1999-Mar 2000) increased total soil water content, approaching the drained upper limit; causing a 600% increase in shoot dry matter yield, similarly higher growth rate (71 kg DM d⁻¹) and higher RUE (~1.7 g DM MJ⁻¹ ), confirming that water availability was the main constraint to lucerne growth. Delayed benefits of summer irrigation, especially in the subsurface treatment, were also observed later (July to October) when lucerne was able to scavenge excess irrigation water and nitrate stored in the 600-1800 mm soil profile, which resulted in increased shoot growth. Drainage below the effective rooting depth was negligible, even under irrigation, confirming that lucerne can dry soil profiles and reduce deep drainage. Average annual water use efficiency was 9 kg DM ha⁻¹ mm⁻¹ under rainfed conditions compared to ~15 kg DM ha⁻¹ mm⁻¹ under irrigated conditions. Shoot dry mattter production was closely related to evapotranspiration in all treatments, however, under rainfed conditions losses from evaporation were proportionally higher compared to irrigated treatments. Sub-surface drip irrigation proved superior to surface irrigation using 22% less water compared to surface sprinkler irrigation treatment with comparable yields. Biological N₂fixation was strongly related to shoot production with 18 to 27 kg N fixed per tonne of shoot dry matter across all seasons and treatments. Dependence on N₂fixation appeared to be unrelated to soil mineral N concentration and amounts of nitrate in the profile (to 1m) were generally quite low <35 kg N ha⁻¹). Soil water dynamics under both rainfed and surface irrigated treatments were adequately simulated by the Agricultural Production System Simulator (APSIM) with RMSD < 10% of the observed means and R² > 0.80 for the total soil profile (0-2000 mm). Simulation of growth and development was less satisfactory. For example, the RMSD was ~50% of observed mean for shoot biomass (R² = 0.68) in the rainfed treatment, and 36% (R² = 0.77) in the irrigated treatment. Overall, simulation of shoot DM production was close to observed values during the growing season (Apr-Nov), however the model was unable to capture the observed shoot yield in response to summer irrigation, with simulated shoot DM 40% less than the observed value in 2000 and 35% less in 2001. N dynamics were poorly simulated under these soil and climate conditions. Amounts of soil mineral nitrogen (kg NO⁻₃-N ha⁻¹) were adequately simulated in rainfed conditions but consistently over-predicted under irrigated conditions. This evaluation of APSIM highlights both good and poor model performance and the analysis indicates the need for caution when applying the model in situations where observed data is scarce. Areas requiring improvements to the model are identified. Overall this research has improved understanding of the limitations to potential production of lucerne in a Mediterranean environment on duplex soils and shown that APSIM-Lucerne can be used confidently for many applications, particularly soil-water dynamics. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1352515 / Thesis (Ph.D.) - University of Adelaide, School of Earth and Environmental Sciences, 2009

The experimental work reported in this thesis quantified the productivity of lucerne over a two-year period (2000-2001) for a Mediterranean climate at Roseworthy in South Australia (34°32′S, 138°45′E), and determined associated dynamics for water and nitrogen in duplex soil. Shoot growth of dryland lucerne was limited primarily by the pattern and amount of incident rainfall, but high temperature (30-35oC) also constrained summer production. These high summer temperatures induced greater production when irrigation was applied, but under the normally dry summer conditions high temperatures combined with soil water deficit (up to 200mm) caused growth to cease. Thus, shoot dry matter yield under rainfed conditions was 4.9 t ha⁻¹ in 2000 (from 7 harvests) and 1.8 t ha⁻¹ in 2001 (from 5 harvests) whereas summer irrigation increased yield to 14.9 t ha⁻¹ in 2000 (7 harvests) and 7.1 t ha⁻¹ in 2001 (5 harvests). Under rainfed conditions the RUE was 0.55 g DM MJ⁻¹ PARi compared with 1.08 g DM MJ⁻¹ PARi in the irrigated treatment in 2000, reducing to 0.4 g DM MJ⁻¹ for the rainfed and 0.7 g DM MJ⁻¹ under limited irrigation in 2001. Lucerne plant population declined from 69 to 20 (plants m⁻²) in the rainfed treatment and the plants partially compensated for this in 2000 by increasing stem density from 300 to 400 m⁻² in 2000 although this declined back to 300 m⁻² in 2001. In all treatments more than 70% of root biomass was in the top 40 cm soil, this was partially due to the vertical distribution of plant available water but also to subsoil constraints to root development below 0.6m. Nevertheless, lucerne was able to extract water and nitrate to 1800 mm soil depth. Large amounts of irrigation >400mm) over summer (Dec 1999-Mar 2000) increased total soil water content, approaching the drained upper limit; causing a 600% increase in shoot dry matter yield, similarly higher growth rate (71 kg DM d⁻¹) and higher RUE (~1.7 g DM MJ⁻¹ ), confirming that water availability was the main constraint to lucerne growth. Delayed benefits of summer irrigation, especially in the subsurface treatment, were also observed later (July to October) when lucerne was able to scavenge excess irrigation water and nitrate stored in the 600-1800 mm soil profile, which resulted in increased shoot growth. Drainage below the effective rooting depth was negligible, even under irrigation, confirming that lucerne can dry soil profiles and reduce deep drainage. Average annual water use efficiency was 9 kg DM ha⁻¹ mm⁻¹ under rainfed conditions compared to ~15 kg DM ha⁻¹ mm⁻¹ under irrigated conditions. Shoot dry mattter production was closely related to evapotranspiration in all treatments, however, under rainfed conditions losses from evaporation were proportionally higher compared to irrigated treatments. Sub-surface drip irrigation proved superior to surface irrigation using 22% less water compared to surface sprinkler irrigation treatment with comparable yields. Biological N₂fixation was strongly related to shoot production with 18 to 27 kg N fixed per tonne of shoot dry matter across all seasons and treatments. Dependence on N₂fixation appeared to be unrelated to soil mineral N concentration and amounts of nitrate in the profile (to 1m) were generally quite low <35 kg N ha⁻¹). Soil water dynamics under both rainfed and surface irrigated treatments were adequately simulated by the Agricultural Production System Simulator (APSIM) with RMSD < 10% of the observed means and R² > 0.80 for the total soil profile (0-2000 mm). Simulation of growth and development was less satisfactory. For example, the RMSD was ~50% of observed mean for shoot biomass (R² = 0.68) in the rainfed treatment, and 36% (R² = 0.77) in the irrigated treatment. Overall, simulation of shoot DM production was close to observed values during the growing season (Apr-Nov), however the model was unable to capture the observed shoot yield in response to summer irrigation, with simulated shoot DM 40% less than the observed value in 2000 and 35% less in 2001. N dynamics were poorly simulated under these soil and climate conditions. Amounts of soil mineral nitrogen (kg NO⁻₃-N ha⁻¹) were adequately simulated in rainfed conditions but consistently over-predicted under irrigated conditions. This evaluation of APSIM highlights both good and poor model performance and the analysis indicates the need for caution when applying the model in situations where observed data is scarce. Areas requiring improvements to the model are identified. Overall this research has improved understanding of the limitations to potential production of lucerne in a Mediterranean environment on duplex soils and shown that APSIM-Lucerne can be used confidently for many applications, particularly soil-water dynamics. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1352515 / Thesis (Ph.D.) - University of Adelaide, School of Earth and Environmental Sciences, 2009

Thèse Droit, Fribourg (Suisse), 1970.

Diss.--Philosophische Fakultät--Freiburg, Schweiz, 1976. / Bibliogr. p. 5-27. Index.

During spring kikuyu-ryegrass pasture has a low dry matter (DM) content (10-12%), is highly digestible and has high levels of soluble carbohydrates. Low rumen pH values have been recorded for cows grazing these pastures even when supplemented with low levels of concentrate. The rumen environment and extent of rumination may therefore be sub-optimal. Supplementation of the pasture with dry roughage may improve rumination, the rumen environment and therefore also milk production performance. The aim of the study was to determine if strategic supplementation of lucerne hay will improve milk production, milk composition and the rumen environment of cows grazing high quality kikuyu/ryegrass during spring and receiving low levels of concentrate. Forty eight high producing Jersey cows were blocked and randomly allocated to one of the following treatments: control (no supplemental roughage), supplementation of 1.0 kg lucerne hay and supplementation of 2.0 kg lucerne hay after morning milking. Cows received 5 kg of dairy concentrate per day during milking. Cows grazed as one group and pasture was allocated to ensure a post grazing height of 10-12 on the rising plate meter (5-6 cm). The average post grazing pasture height for the experimental period was 10.83±1.68 (n=73) on the RPM (5.42 cm). There were no differences (P >0.10) between the treatments for 4% fat corrected milk production, which were 22.2 kg/d for the control, and 22.5 kg/d and 22.9 kg/d for the 1 kg and 2 kg lucerne treatments respectively. Milk fat and protein percentage was not affected (P >0.10) by supplementation of lucerne hay. The milk lactose content of cows receiving the control and 1 kg lucerne hay treatments were higher (P <0.05) than those of cows receiving the 2 kg lucerne hay treatment. Eight rumen cannulated Jersey cows were randomly allocated to either the control or the 2 kg lucerne hay treatment in a cross-over design. These cows grazed together with the cows of the production study and received the same dairy concentrate. Rumen pH was measured for 48 hours with 10 minute intervals using an automated pH logging system. Rumen samples were taken at 08:00, 14:00, 20:00 and 02:00 and were analysed for ammonia-nitrogen (NH3-N), volatile fatty acids (VFA) and pH. An in sacco study was conducted to determine DM and neutral detergent fibre (NDF) disappearance of ryegrass. There were no differences (P >0.10) between treatments in overall mean pH, measured with either the logging systems or with the portable pH meters averaging 6.18 and 6.11 for cows receiving the control and the 2 kg lucerne treatment respectively. The mean rumen NH3-N did not differ (P >0.10) between treatments. The mean concentration of acetic acid and the total VFA concentration was higher (P <0.05) for cows receiving the 2 kg lucerne treatment compared to the control. There were no differences (P >0.10) between treatments in the DM or NDF disappearance of ryegrass after 24 hours. Supplementation of lucerne hay to cows grazing well managed kikuyu-ryegrass pasture during spring did not improve milk production, milk composition, rumen pH or in situ NDF disappearance of ryegrass Results suggest that cows grazing kikuyu/ryegrass pastures supplemented with low levels of concentrate consume sufficient eNDF to maintain a favourable rumen environment and normal milk composition. Copyright / Dissertation (MSc(Agric))--University of Pretoria, 2012. / Animal and Wildlife Sciences / unrestricted

The satellite RNA of Lucerne Transient Streak Virus (LTSV) is a 322-nucleotide, single-stranded circular RNA that has a rod-like structure very similar to that of viroids. As it does not encode any translation products and cannot replicate independently of a helper virus, the satellite RNA is proposed to rely on viral-encoded proteins for the replication and/or cell-to-cell movement that facilitate its systemic infection in a host. To investigate the requirements for replication of the LTSV satellite RNA, transgenic plant systems were generated to express the viral RNA-dependent RNA polymerase and predicted viral transport protein independently as well as in combination. Results of infectivity assays of these transgenic lines demonstrated for the first time that the viral-encoded RNA-dependent RNA polymerase is necessary and sufficient for the replication of LTSV satellite RNA, and that no additional viral proteins are required for its cell-to-cell or systemic transport.

The satellite RNA of Lucerne Transient Streak Virus (LTSV) is a 322-nucleotide, single-stranded circular RNA that has a rod-like structure very similar to that of viroids. As it does not encode any translation products and cannot replicate independently of a helper virus, the satellite RNA is proposed to rely on viral-encoded proteins for the replication and/or cell-to-cell movement that facilitate its systemic infection in a host. To investigate the requirements for replication of the LTSV satellite RNA, transgenic plant systems were generated to express the viral RNA-dependent RNA polymerase and predicted viral transport protein independently as well as in combination. Results of infectivity assays of these transgenic lines demonstrated for the first time that the viral-encoded RNA-dependent RNA polymerase is necessary and sufficient for the replication of LTSV satellite RNA, and that no additional viral proteins are required for its cell-to-cell or systemic transport.

This dissertation examines Tolstoy’s reevaluation of his creative approaches to writing through the medium of his experimental pedagogical work with the peasant children on his estate. It is argued that Tolstoy’s pedagogical interlude forms an important bridge to the writer’s fiction and should not be viewed as a digression from his development as a writer, but as an integral part of it. This project explores how the educational essays Tolstoy wrote during this period facilitate his transition from championing the aesthetic theory of “pure art” in his formative years as a writer for The Contemporary to a more mature author of War and Peace, the major masterwork that is imbued with conclusions reached during his pedagogical interlude. Tolstoy’s evolution as a writer is examined in the context of his relationship to the aesthetic ideas of the 1850’s that became a springboard for Tolstoy’s later aesthetic concepts. A comprehensive textual analysis of Tolstoy’s lesser known early works such as Notes from Lucerne and “Albert” is undertaken in order to highlight some of their important stylistic peculiarities that provide a valuable insight into the authorial presence and the nature of Tolstoy’s aesthetic rhetoric. Further, it is demonstrated how the school at Yasnaya Polyana becomes the writer’s experimental workshop, a testing ground for Tolstoy’s pedagogical theories and his creative ideas, which he checks against his students’ perception. Finally, the study is concluded by examining Tolstoy’s most encompassing work, his epic novel War and Peace through the medium of his educational writings and ideas. By locating some of the main concepts of his pedagogical philosophy in the context of this monumental masterwork, we illuminate their meaning more clearly as filtered through the prism of Tolstoy’s creative thought in order to demonstrate to what extent Tolstoy’s educational ideas informed his creative writings. It is established that all the central principles of Tolstoy’s educational thought such as his pedagogy of freedom, his ideas of aesthetic education through reading, art and music, his religious and moral education found their reflections on the pages of War and Peace and commend a great deal to a modern educator. / text

This research was conducted at the University of KwaZulu-Natal, Pietermaritzburg, South Africa. The research encompasses five different studies to assess nutrient cycling in intensive and extensive grazing systems with a view to optimising livestock production. The first study was designed to assess the effect of teff-lucerne mixtures on teff, lucerne and teff-lucerne mixture yields. Lucerne and teff-lucerne mixtures benefited from the association. The overall soil N content of the teff-lucerne mixture plots was greater than the teff alone plots. The second study focused on teff-leucaena association evaluation. It had two leucaena plant row spacings as treatments, 180cm and 120cm, respectively. Teff grown in mixture with leucaena produced a total teff dry matter (DM) of 7931.57 kg ha¯¹ for the 180cm row spacing and 8329.57 for the 120cm row spacing compared to the 3548.93 kg ha¯¹ of DM obtained from the teff alone treatment. The teff-Ieucaena stand also had a greater DM yield response to leucaena row spacing compared to the teff alone. In terms of nutritive quality, all stands from the teff-leucaena plots were better than the quality obtained from the teff alone plots. Total N content of teff from the l80cm row spacing was 21.83 g kg¯¹ and that from the 120cm 16.07 g kg¯¹ compared to the total nitrogen (N) content of 19.77 g kg¯¹ of the teff alone treatment. The total phosphorus (P) content was 2.73, 1.96 and 2.07 g kg¯¹ for the 180cm, 120cm and teff alone treatments respectively. However, the total soil N content was higher for the teff alone plot than for the teff-leucaena plots, which are 1.91, 1.48 and 100 g kg¯¹ for the teff alone, 180cm and 120cm treatments respectively. The third study was designed to assess the effects of different N fertilizer application rates on teff yield response. The rates applied were 0, 50, 100 and 150 kg N ha¯¹. There was significant difference in teff response of the three N fertilizer application rates compared to the control and teff DM yield response was lower for the 150 kg N ha¯¹ (838 kg ha¯¹) treatment compared to the control (553 kg ha¯¹). Both teff DM and nutritive value were higher in the plots treated with N fertilizer than in the plot which received no N fertilizer (control). The soil N content was also higher in those plots treated with N fertilizer. Study four was conducted on the Department of Grassland Science's grassland management techniques trial field at Ukulinga. The effects of nutrient cycling under different management techniques such as burning, mowing and grazing on grass yield response, plant quality and soil nutrients were assessed. However, the response of grass DM yield and P content was not significant but the three treatments had a significant effect on grass N content. Their effect on soil N content was also significant and the grazing plot had the greatest soil N levels. The last study was conducted in the rural areas of Okhombe and Zwelitsha to assess the effects of grazing intensity on grass yield response, plant quality and soil nutrient status at different distances from homesteads. Grass DM yield and nutritive value declined when distance from the homestead increased. The soil N content also was higher nearer to the homestead than further away. Most farmers, particularly in developing countries including those in Eritrea, often experience that their animals prefer forages from some plants such as lucerne, leucaena, and other indigenous leguminous plants. They also observe that they get greater yield from crops grown near leguminous plants or in rotation with legumes. They are also still using manure from their animals to fertilize their croplands. Therefore, it is still the duty of the researchers to demonstrate to farmers on farm studies to convince farmers that it is because leguminous plants have the ability to add quality and quantity to the feed of the animals and soil nutrients to the croplands. Hopefully, this study will convey to farmers the use of growing integrated grassllegume pastures and crops, and illustrate that livestock have their own role in transporting nutrients and hence use them as good means of distributors of soil nutrients. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2004.

The effect of continuous monoculture of sorghum, mungbean, oats, greenpanic and luceren on the nitrogen status of a brown clay soil from Narayen, South East Queensland was studied using biological and chemical methods. the soil nitrogen status was estimated by using indices of nitrogen availability i.e. waterlogged incubation method as the biological method and 2 M KCL, phosphate-borate buffer and 0.01 M CaCl_2 as rapid chemical methods. Total soil nitrogen and organic carbon were also included as estimates of soil nitrogen status. The results obtained by the waterlogged (WL) method were used to evaluate the results obtained by the three rapid chemical methods. The results show that of the three rapid chemical methods 2 M KCL was the most closely correlated with the waterlogged incubation method. Total N and organic C were also highly correlated with the WL method and they may have value as indices of nitrogen availability. The available N, total N and organic C contents in the 0-5 cm and 5-15cm layer soils were consistently higher under greenpanic and lucerne than for the annual crop treatments. The available N contents as determined by the WL method in the 0-5 cm and 5-15 cm soil layers under greenpanic and lucerne ranged from 75.6 to 126.5 ug N/g soil and 53.2 to 106.7 ug N/g soil, respectively, whereas the values under the annual crop treatments ranged from 13.2 to 75.3 ug N/g soil and 25.6 to 66.1 ug N/g soil, respectively. The total N contents in the 0-5 cm and 5-15 cm layer soils under the greenpanic and lucerne ranged from 0.29 to 0.38 % and 0.20 to 0.33 %, respectively, whereas the values under the annual crop treatments ranged from 0.17 to 0.31 % and 0.17 to 0.25 %, respectively. The availability of the total N as indicated by the available N as a percentage of the total N in the 0-5 cm and 5-15 cm layer soils under the greenpanic and lucerne ranged from 2.6 to 4.0 % and 2.1 to 3.2 %, respectively, whereas the values under the annual crop treatments ranged from 0.8 to 3.8 % and 1.5 to 2.4 %, respectively. In addition the organic C contents in the 0.5 cm and 5-15 cm layer soils under the greenpanic and lucerne range from 2.4 to 4.0 % and 2.0 to 3.5 %, respectively, whereas the values under the annual crop treatments ranged from 1.4 to 3.3 % and 1.7 to 2.7 %, respectively.