Effect of potassium and potting-bag size on foliar biomass and related attributes and oil composition of rose geranium (Pelargonium graveolens)

Published ArticleThis study was conducted to evaluate the effect of four concentrations of potassium (K; 1.3, 3.3, 5.3 and 7.3 mmol L−1) and two potting-bag sizes (5 and 10 L) on foliar biomass and related attributes and oil composition of rose geranium (Pelargonium graveolens). Plants were grown in a climate-controlled greenhouse at the University of the Free State and treatments were arranged in a split plot design. Potassium concentrations were allocated to the main plots and potting-bag size to the subplots replicated three times. Plant height, K tissue content, linalool, geraniol, geranyl formate and citronellol:geraniol ratio were affected by the K application. Plant height, number of branches, branch:height ratio, foliage fresh mass, K tissue content and oil yield were affected by the potting-bag size. Foliar fresh mass was significantly increased by the interaction between K concentration and potting-bag size. Growers may use a 5.3 mmol L−1 K concentration and a 5 L potting bag for optimum production of rose geranium under soil-less cultivation

Genetic Diversity Analysis of Soybean (Glycine max (L.) Merr.) Genotypes Making Use of SSR Markers

Published ArticleIn this study, we aimed to investigate the genetic diversity and polymorphism among 30 soybean genotypes maintained by the ARC using simple sequence repeat (SSR) markers. Soybean genotypes were characterized using 20 SSR primers. DNA was extracted using the standard cetyl trimethylammonium bromide method and amplified using PCR. Allele size was determined via comparison with a 100 base pair (bp) DNA ladder. Molecular data were analyzed, and a dendrogram and matrix were generated using GGT 2.0 software. A total of 216 alleles with an average of 10.8 alleles per locus were detected. The allele sizes ranged between 2 and 33 bp with an average of 18.7 bp. The polymorphic information content among genotypes varied from 0.85 (Satt001) to 0.75 (Satt43) with an average of 0.716, and heterozygosity ranged from 0.87 to 0.78 with an average of 0.7485. The most diverse genotypes were B 66 S 31, 69S 7, and R5-4-2 M, which indicated the efficiency of the SSR markers for the detection of genetic diversity. The results of the current study revealed the diversity among the soybean genotypes tested, which might aid breeders in the future in the selection of parents for breeding

Soybean Production, Constraints, and Future Prospects in Poorer Countries: A Review

This study was carried out to examine patterns of soybean production, constraints, and possible solutions in poorer countries such as Southern African countries. It was observed that the success of soybean in top-producing countries was characterized by large acreage of land, with a good supply of inputs coupled with intensive management and access to competitive markets. Africa is a minor player in the soybean industry as it supplies less than 1% of the world’s soybeans. Because the crop is not for direct household consumption, it is produced on a small-scale and treated as a zero inputs crop. This has resulted in a persistent yield gap, with levels reaching only a third of those obtained in developed countries. There is under-usage of inputs such as irrigation, fertilizers, and improved seed. There is need for a definite shift from small to large-scale production. Limited access to inputs, poor adoption of technologies and restricted markets usually also compromise production. The global demand for soybean due to a growing feed industry, biodiesel, industrial demand, and bias for plant-based protein, is going upwards. New soybean frontiers will likely be present in future, and countries whose production levels lag could take advantage of this situation

Financial Crisis and the South African Agricultural Sector: A Computable General Equilibrium (CGE) Analysis

Published ArticleThis study examines the impact of financial crisis as a shock on agricultural sector of the South African economy. Agriculture is regarded as a critical source of foreign exchange, employment and poverty alleviation in South Africa. Using a computable general equilibrium model of the South African economy based on the theory of ORANI-G framework, it was discovered that the impact of the financial crisis on agricultural sector was harmful to the economy. Job losses were recorded in the sector as well as decline in household demand. The financial crisis was also found to be harsh on domestic prices and general household consumption levels. The findings have far-reaching implications for research and practice. The results provide evidence of the vulnerability of the South African agricultural sector to any financial shocks

Production Constraints and Improvement Strategies of Cowpea (Vigna unguiculata L. Walp.) Genotypes for Drought Tolerance

Cowpea (Vigna unguiculata L. Walp. L) is an important leguminous crop largely grown by smallholder farmers in sub-Saharan Africa for food security and animal feed. The objective of this study was to review the production constraints and improvement strategies of cowpea genotypes for drought tolerance. Data were analysed through use of literature review from various sources. In sub-Saharan Africa, cowpeas are produced mainly from West Africa, which accounts for 60% of worldwide production. A lot of pests and diseases affect cowpeas, and this often results in total crop loss. Through continuous improvement, many new cultivars are continually being identified and genetically characterised, and it is thus necessary to evaluate these new lines under different environments. There is a need for multidisciplinary collaborations among breeders and other relevant stakeholders such as farmer and extension workers because the improved cultivars must be according to the farmers preferred traits. Due to declining rainfall pattern in sub-Saharan Africa, there is an urgent requirement for cowpea breeding programmes that focus on developing varieties with short maturity, drought, pest, and disease tolerance. The present review discusses the constraints and improvement strategies of cowpea varieties for drought tolerance