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Nutritive Value of Four Lucerne Cultivars Planted in Two Soil Types at Bathurst Research Station, Eastern Cape Province, South Africa

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Agricultural Sciences 2022年第10期13卷 1048-1056页

作者： Mhlangabezi Solontsi Mfundo Phakama Maqubela johan adam van niekerk Jan Willem Swanepoel Gideon Jordaan Unathi Gulwa Sive Tokozwayo Department of Rural Development and Agrarian Reform Dohne ADI Stutterheim South Africa Centre for Sustainable Agriculture University of Free State Bloemfontein South Africa Department of Rural Development and Agrarian Reform Cradock Experimental Farm Cradock South Africa

Medicago sativa (lucerne) is a widely used perennial fodder crop and ranked amongst the highly nutritive fodders globally. This study assessed the nutritive value (i.e. CP % and TDN %) of four lucerne cultivars under two soil types at Bathurst Research Station. A random grid (quadrant) sampling method was used for sampling and samples were submitted to the laboratory for analysis to determine forage quality. Data collection was carried out by separating harvested biomass for each cultivar using clean packs, weighed and dried at 70˚C for 48 hours then crude protein (CP %) and Total Digestible Nutrients (TDN %) were determined. The results of the study showed that soil type (site) had a significant (P < 0.05) effect on the overall quality of dry matter produced. In soil 1 (S1) the overall CP % content was 11.48% while it was 19.03% in soil 2 (S2). Cultivar 3 (KKS 9911) was the least nutritive cultivar in site 1, while the same cultivar was the most nutritive cultivar in site 2 pertaining CP content. Soil type also significantly affected (P < 0.05) the overall total digestible nutrient (TDN %) content of different lucerne cultivars. In S1, C4 (WL 525) had the highest (P < 0.05) TDN content in comparison to the rest of the cultivars while in the same soil type C1 (SA Std.) had the least TDN content. The four tested lucerne cultivars generally produced highly nutritive lucerne in S2 while they produced less nutritive lucerne in relation to both CP and TDN content in S1.

关键词： Forage Quality Nutritive Value Fodder

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Productivity Evaluation of Four Medicago sativa Cultivars under Two Water Regimes (Irrigated and Non-Irrigated) and Two Soil Types at Bathurst Research Station in the Eastern Cape Province, South Africa

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Agricultural Sciences 2022年第3期13卷 438-447页

作者： Mhlangabezi Solontsi Mfundo Phakama Maqubela johan adam van niekerk Jan Willem Swanepoel Gideon Jordaan Unathi Gulwa Sive Tokozwayo Nkululeko Nyangiwe Department of Rural Development and Agrarian Reform D&#246 hne ADI Stutterheim South Africa Centre for Sustainable Agriculture University of Free State Bloemfontein South Africa Department of Rural Development and Agrarian Reform Cradock Experimental Farm Cradock South Africa Department of Agriculture and Animal Health University of South Africa Pretoria South Africa

Medicago sativa (lucerne) is a perennial and drought tolerant fodder crop which is widely used as feed for livestock in South Africa. This study evaluated four lucerne cultivars under two water regimes and also determined the effect of soil type on lucerne biomass production. To determine dry matter production per cultivar per treatment, a random grid (quadrant) sampling method was used and all biomass within that radius was cut to 5 cm above the ground level in each plot. All biomass sampling was done just before regrowth commences. Biomass data collection on four lucerne cultivars belonging to different dormancy groupings (WL 711, WL 525 HQ, KKS 9911 and SA Standard) were collected seasonally under different soil types on both irrigated and non-irrigated plots and analysed. Soil type (site) had a significant (P < 0.05) effect on the overall quantity of dry matter produced as more dry matter was produced in site 2 (S2) in comparison to site 1 (S2). Different levels of water application (moisture supplementation) also affected the quantity of dry matter produced in each soil type. The once-a-month irrigation treatment (Ir1) led to the production of superior dry matter yield on SI even though the effect was not significant. In S2 twice a month irrigation treatment (Ir2) produced the highest dry matter, however, this effect was significant (P < 0.05) only in comparison with zero irrigation (Ir0) treatment. Cultivar 3 (KKS 9911) was the least productive cultivar in S1, while the same cultivar was the least productive cultivar in S2. These findings show that both soil type and irrigation levels had a significant (P < 0.05) effect on the total dry matter production of the tested Lucerne cultivars belonging to different dormancy groupings.

关键词： Biomass Cultivar Dry Matter Dormancy Groupings

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Sustainability Assessment of Banana (Musa spp.) Yield Gap Reduction through Value Chain Development Interventions in Smallholder Farming Systems in Manicaland, Zimbabwe

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Agricultural Sciences 2024年第8期15卷 962-992页

作者： Mthintwa Tawanda Hove Hlamalani Ngwenya johan van niekerk Faculty of Agriculture and Natural Sciences Center of Sustainable Agriculture Extension and Rural Development University of the Free State Bloemfontein South Africa

This study evaluated the effectiveness of donor supported agricultural value chain development projects in sustainably narrowing yield gaps for banana smallholder farmer producers in Manicaland, Zimbabwe. The study used a mixed methods research design that relied on farmers records for the quantitative analysis and focus group discussion and in-depth interviews for key experts for the qualitative aspects. A mix of regression analysis, t-tests, Pearsons’s correlation and analysis of variance statistical methods were used for the quantitative analysis while thematic response analysis was used for the qualitative engagements. The findings showed that by the end of the activity, the project had successfully narrowed the banana yield gaps to 18.66 tons per hectare working with a potential yield base of 40 tons. However, 5 years after the project closure the yield gap had fallen to 24.7 tons indicating a lack of sustainability of yield gap reduction. However, the yield gap slump does not override the fact that farmers on average were still able to sell approximately 5 tons per every 6 months after 5 years from the project closure which is beyond any poverty threshold. This suggests genuine upward economic mobility. Additionally, in analyzing what factors had the greatest influence on yield gap reduction, the access to fertilizer ranked highest where genetics, irrigation and improved agronomy followed in that respective order. The study further showed that farmers who receive value chain development support whilst at an already commercialized state tend to maintain productivity thresholds higher in comparison to those who are at a pre commercial state. This is evidenced by the fact that the pre commercial farmers had a yield reduction of 30.83 percent after 5 years of the project closure whereas the former realized a productivity growth of 7.84%. In conclusion, whilst the intervention was successful in transitioning farmers out of poverty, more investment should be made to

关键词： Yield Gap Value Chain Development Soil Health Varietal Replacement Rate Sustainability and Economic Mobility

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Demography and Socio-Economic Aspects on Irrigated Smallholder Agricultural Enterprises and Their Association with the Cultivation of Maize (Zea mays L.) as a Selected Field Crop

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Agricultural Sciences 2024年第7期15卷 729-741页

作者： Tsumbedzo Jutas Mavhungu Azwihangwisi Edward Nesamvuni Khathutshelo Alfred Tshikolomo Ndivhudzannyi Sylvestor Mpandeli johan Adriaan van niekerk Department of Sustainable Food Systems and Development University of the Free State Bloemfontein South Africa Limpopo Department of Agriculture and Rural Development Polokwane South Africa Water Research Commission of South Africa Gezina South Africa

The purpose of this study is to correlate demography and socio-economic aspects at Irrigated Smallholder Agricultural Enterprises and their association with the Cultivation of Maize in order to determine its positive impacts at irrigated smallholders’ agricultural entrepreneurs’ household. Chi-square test was used as descriptive analysis method. The Fischer Exact tests were employed to test demography (gender, age, education, and income) in winter and summer production season of irrigated smallholder agricultural enterprises and their association with the cultivation of selected field crop (i.e. maize). The results show that gender results were not being statistically significant, as measured by the Phi measure of effect size, φ = 0.149, p = 0.011, and φ = 0.05, p = 0.392 in summer. As far as age is concern, it appears to be a statistically significant association between cultivating maize and age in winter, φ = 0.046, p = 0.730 in winter and φ = 0.172, p = 0.013. Education winter result not being statistically significant, the effect size showed a weak association, as measured by the Phi measure of effect size, φ = 0.112, p = 0.305 and φ = 0.035, p = 0.948 in summer. Income result not being statistically significant, as measured by the Phi measure of effect size, φ = 0.049, p = 0.399 and φ = 0.081, p = 0.166 in summer. In conclusion, the study shows that the development of best management practices must be based on a comprehensive analysis of the livelihoods and irrigated smallholder agricultural enterprise farming styles of participating irrigated smallholder agricultural entrepreneurs.

关键词： Maize Association Irrigated Smallholder Agricultural Enterprises Demography Livelihoods

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In silico product design of pharmaceuticals

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Asian Journal of Pharmaceutical Sciences 2016年第4期11卷 492-499页

作者： johan Boetker Dhara Raijada johanna Aho Milad Khorasani SФren V.SФgaard Loerke Arnfast adam Bohr Magnus Edinger Jorrit J.Water Jukka Rantanen Department of Pharmacy Faculty of Health and Medical SciencesUniversity of Copenhagen

The increasing demand for personalized medicine necessitates the production of easily customizable dosage forms. As the number of possible dosage forms may scale toward infinity, their uniqueness requires a versatile production platform and numerical simulation in order to be manufactured efficiently. A mathematical description of these systems is the only feasible approach to manage such diverse properties of different products. However,experimental verification is still essential for evaluation of processability and related concomitant phenomena, such as possible solid state changes that may occur during production and storage.

关键词： Personalized medicine Simulation Rheology Imaging Continuous manufacturing Extrusion

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多种族动脉粥样硬化和空气污染研究中预测多空气污染物浓度的统一时空建模方法

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环境与职业医学 2015年第9期32卷 866-866页

作者： Joshua P.Keller Casey Olives Sun-Young Kim Lianne Sheppard Paul D.Sampson adam A.Szpiro Assaf P.Oron johan Lindstr?m Sverre Vedal Joel D.Kaufman

[背景]在空气污染暴露与慢性健康影响之间关系的队列研究中,需要对很长一段时间的暴露进行预测。[目的]作为多种族动脉粥样硬化和空气污染研究(MESA Air)的一部分,我们利用从1999年至2012年初美国6个都市地区的数据,建立一种统一的建模... 详细信息

[背景]在空气污染暴露与慢性健康影响之间关系的队列研究中,需要对很长一段时间的暴露进行预测。[目的]作为多种族动脉粥样硬化和空气污染研究(MESA Air)的一部分,我们利用从1999年至2012年初美国6个都市地区的数据,建立一种统一的建模方法,以预测细颗粒物、二氧化氮、氮氧化物和黑碳(通过光吸收系数来测量)。[方法]获得调控网络的监测数据,并用MESA Air社区位置和参与者家中收集到的研究测量指标对这些数据进行补充。在每个区域,我们采用一种包括长期空间均值、带有空间变化系数的时间趋势以及时空残差的时空模型。模型的均值结构来自于一组地理协变量,使用偏最小二乘回归减小这组值。根据观测到的时间序列估计时间趋势,并用空间平滑方法来增加观察值间的强度。[结果]大部分模型的预测精度都较高,对监测点和固定位置来说,大部分地区和污染物的交叉验证R2(R2CV)>0.80。在家庭所在地,总R2CV范围为0.45至0.92,时间校正的R2CV范围为0.23到0.92。[结论]这一新颖的时空建模方法为多个区域的4种污染物提供了精确的预测值。我们得出了MESA Air研究特定参与者的预测值,以了解长期空气污染暴露对健康的影响。这些成果突显出这一先进的建模方法可以被更广泛地用于当代队列研究中。

关键词：动脉粥样硬化污染物浓度时空模型空气污染建模方法预测精度种族光吸收系数

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