College Algebra (University of North Georgia)

This Grants Collection Open Textbook for College Algebra was created under a Round Two ALG Textbook Transformation Grant. Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process. Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials: Linked Syllabus Initial Proposal Final Reporthttps://oer.galileo.usg.edu/mathematics-collections/1010/thumbnail.jp

Support for College Algebra

This Grants Collection for Support for College Algebra was created under a Round Two ALG Textbook Transformation Grant. Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process. Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials: Linked Syllabus Initial Proposal Final Reporthttps://oer.galileo.usg.edu/mathematics-collections/1013/thumbnail.jp

Calculus I (University of North Georgia)

This Grants Collection for Calculus I was created under a Round Two ALG Textbook Transformation Grant. Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process. Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials: Linked Syllabus Initial Proposal Final Reporthttps://oer.galileo.usg.edu/mathematics-collections/1009/thumbnail.jp

Foundations for College Algebra

This Grants Collection for Foundations for College Algebra was created under a Round Two ALG Textbook Transformation Grant. Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process. Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials: Linked Syllabus Initial Proposal Final Reporthttps://oer.galileo.usg.edu/mathematics-collections/1011/thumbnail.jp

Intermediate Algebra

This Grants Collection for Intermediate Algebra was created under a Round Two ALG Textbook Transformation Grant. Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process. Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials: Linked Syllabus Initial Proposal Final Reporthttps://oer.galileo.usg.edu/mathematics-collections/1012/thumbnail.jp

Precalculus (University of North Georgia)

This Grants Collection for Precalculus was created under a Round Two ALG Textbook Transformation Grant. Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process. Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials: Linked Syllabus Initial Proposal Final Reporthttps://oer.galileo.usg.edu/mathematics-collections/1001/thumbnail.jp

Effect of Salt Stresses on Seed Germination and Early Seedling Growth of Camelina sativa L.

Camelina sativa is a promising low-input, high yielding biodiesel crop that can be suitable to grow on marginal lands and is a good source of omega-3 fatty acids. But, saltiness is an overall issue of agriculture that constrains the germination, development and productivity of plant because of osmotic and ionic poisonous quality impacts. The aim of this study was to assess the effect of salinity (NaCl and KCl) on germination and early seedling growth of Camelina sativa. Camelina sativa seeds were obtained from agricultural research sector of Wachemo University. In the laboratory, six salinity levels of NaCl and KCl (0, 1, 2, 3, 4 and 5 g/L) were prepared and arranged in completely randomized design with four replications. The result of the study revealed that C. sativa seedlings were differ significantly (p<0.05) on speed of germination, germination percentage, germination index, shoot length, root length, vigor index, root shoot ratio and seedling fresh weight, relative injury rates  of NaCl and KCl, shoot height reduction and root height reduction. However, there is no significant effect between salt type versus salinity level and salt type in all parameters tested except shoot length and shoot height reduction at 5% significant level. The increase in both salts (NaCl and KCl) concentration in culture medium causes a significant decreases in speed of germination, germination percentage, germination index, shoot length, root length, vigor index, root shoot ratio and seedling fresh weight of the salt treated C. sativa seeds as compared with the control (C. sativa seeds watered with distilled water). Similarly, relative injury rates NaCl and KCl shoot height reduction, root height reduction were highly increased as salinity level increases. Generally, as the concentration of NaCl and KCl was increased the overall germination and early seedling performance of C. sativa decreased. The effect of salinity on physiology, molecular and biochemical of properties of C. sativa should be studied. Keywords: Camelina sativa, Salinity effect, NaCl, KCl, Seed germination, Seedling growth

Reduced Tillage and Intercropping as a Means to Increase Yield and Financial Return in the Drylands of Tigray, northern Ethiopia: A Case Study under Rainfed and Irrigation Conditions

Intensive tillage is a major sustainability concern in cereal dominated cropping systems in the drylands of Tigray, Ethiopia. Hence, on-farm trials were conducted to investigate the yield and economic advantage of reduced tillage and intercropping for two seasons. A factorial experiment in a complete randomized block design was carried out at Adigudom located in Hintalo-Wajirat district in South-Eastern Tigray in 2014 (rain-fed) and 2015 (irrigated). The experiment consisted of four tillage frequencies (zero, one, two and four) and three types of cropping systems (sole maize, sole soybean and maize-soybean intercropping) in three/four replications. Maize, variety “Melkassa 2”, and soybean, variety “Awassa 91” were used. Grain and biomass yields, and harvest index of both crops were analysed. Yield advantage of intercropping was evaluated using land equivalent ratio (LER) and partial budget analysis was used for the financial evaluation. The grain and biomass yields of both crops were significantly increased (p<0.05) as the tillage frequencies increased from zero to four in both seasons but the frequent tillage with sole cropping was not economically viable as the two times tillage with maize-soybean intercropping gave 126% greater net benefit compared to the four times tillage sole maize, which is practiced by farmers in the study area. The net benefit was strongly influenced by the main effects of tillage and intercropping in both seasons (p<0.001) and by their interaction in 2014 (p<0.05). Significantly higher LER (1.87-2.12) was recorded from maize-soybean intercropping over sole cropping in all the tillages and both seasons. Hence, two alternative options are suggested that farmers could apply in the drylands of Tigray: (i) keeping the sole cropping culture of maize production, and reducing number of tillages from 4 to 2 that would give 374%and 705% Marginal Rate of Return (MRR), respectively, under the rainfed and irrigated conditions compared to zero tillage sole maize; or (ii) intercropping maize with soybean and reducing tillage frequency from 4to 2 that would give 608% and 585% MRR in the respective growing seasons, compared to zero tillage maize-soybean intercropping. Taking these results into account, two times tillage combined with maize-soybean intercropping can be a good option in dryland areas of Tigray to achieve higher total intercrop yield at a low cost and larger LER. Moreover, reduced tillage can minimize soil degradation and benefit farmers with poor access to draft power or female-headed households constrained with labour for ploughing.Keywords: Tillage; Intercropping; Maize; Soybean; Tigray; Ethiopia.Please find erratum for this article here: https://dx.doi.org/10.4314/mejs.v11i1.1

Grouping of environments for testing navy bean in Ethiopia

Common bean variety selection within its production environment is often challenged by the occurrence of significant genotype-by-environment interactions (GEI) in the variety development process. Grain yield performance of 16 navy bean (Phaseolus vulgaris L.) lines was tested in a multi-environment variety trial during 2010 and 2011 main growing seasons of Ethiopia. Field experiments were conducted in Randomized Complete Block Design (RCBD) with three replications in 14 rainfed environments of the major common bean growing areas. The objectives were to assess the line by environment interactions (LEI), determine stable genotypes, and grouping of test environments. Significant differences were found among the lines for grain yield on each environment and combined over environments. The combined analysis of variance across environments indicated that both environment and LE interactions were significantly influenced lines yield. All interactions in relation to L×E showed high significant difference (P<0.01) for grain yield. Statistical methods as AMMI, GGE and some stability parameters were used to describe the LE interaction and to define stable lines in relation to their yield. The highest yield (2435 kg ha-1) was obtained from the line ICA BUNSI X SXB 405/1C-C1-1C-87. The stability analysis also identified lines ICA BUNSI X SXB 405/1C-C1-1C-87 and ICA BUNSI X SXB 405/1C-C1-1C- 37 as the most stable lines. Lines identified as superior differed significantly from the standard varieties and can be recommended for use by farmers in the bean growing areas of Ethiopia. Cluster analysis, based on grouping of locations showed that Melkassa, Alemtena and Haramaya as potential and high yielding, but Jimma, Bako, Pawe, Areka, Assosa and Sirinka as low to medium yielding locations