Tea Value Chains Viability in Limpopo Province of South Africa: A Cost–benefit Analysis

The research was conducted to investigate the production of value-added tea as part of the resuscitation of Tshivhase-Mukumbani Tea Estate. Data were mainly obtained from records kept at the Tshivhase-Mukumbani Tea Estate, through a review of literature and interviews of the selected respondents. Evaluation of economic viability of the value-adding initiative was based on Net Present Value (NPC) and the Benefit-Cost Ratio (BCR) calculated from time-series data obtained for the period 2005–2012. The quantity of value-added tea produced varied across years, geographical locations, and seasons, with production higher for wetter seasons. The NPV was consistently negative, while the BCR was below unity throughout the study period, implying that the value-adding initiative was economically not feasible. Initiatives for achieving economic sustainability of the value addition were (1) Improve the marketing of the made tea brand Midi Tea as organic and longer shelf life. (2) Good labor contracting management practices to deal with labor disputes and unrest. (3) Good supply chain and procurement management practices to reduce the cost of production (4) Monitoring the impact of climate variability and mitigate by providing irrigation (5) Intercropping tea with a suitable winter yielding crops such as avocadoes or Macadamia

Unravelling the impact of soil types on zinc, iron, and selenium concentrations in grains and straw of wheat/Amblyopyrum muticum and wheat/Triticum urartu doubled haploid lines

The concentration of mineral nutrients in plants is associated with bioavailabilities of soil mineral nutrients, which are regulated by various soil physio-chemical properties. A pot experiment was conducted to investigate the effects of soil type on grain and straw zinc (Zn), iron (Fe) and selenium (Se) concentrations of wheat/Amblyopyrum muticum and wheat/Triticum urartu doubled haploid lines. A set of 42 treatments in a factorial combination with 21 genotypes and two soil types collected from Ngabu and Chitedze Research Stations in Malawi was laid in a randomised complete block design (RCBD) in three replicates. Pre-experiment soil Zn and Fe were extracted using DTPA extraction method followed by analysis with inductively coupled plasma-mass spectrometry (ICP-MS). Aqua-regia hotplate acid digestion was used to extract soil Se and analysis was done using ICPM-MS. Grain and straw samples were digested using nitric acid digestion (HNO3) and analysed using ICP-MS. Soil analysis results showed that the two soils had the same textural class (Sandy clay loam), but different mineral concentrations, pH levels and percentage organic matter. Analysis of variance revealed a ~two-fold higher Zn concentration in grains grown in low pH, high Zn soils (Chitedze soils) compared to grains grown in high pH, low Zn soils (Ngabu soils). Variation in grain Zn concentration was associated with the genotypes (p = 0002), soil type (p = <0.0001), and their interaction (p = 0.035). Grain Fe was 1.3-fold higher in low pH than in high pH soils, and it was influenced by genotypes (p = < 0.0001) and soil type (p = <0.0001). Grain Se was highly associated with soil type (p = <0.0001), and it was 30-fold higher in high pH than in low pH soils. Straw Zn was generally higher in plants grown in Chitedze soils than Ngabu soils, whilst straw Se was higher in plants grown in Ngabu soils than Chitedze soils. The findings demonstrate the significance of soil physio-chemical properties for mineral accumulation and distribution to plant parts, thus informing future breeding programs on important considerations on crop genetic biofortification with the three mineral elements

Econonic analysis of value addition on tea a case study of the Mukumbani/Tshivhase Tea Estate, Vhembe District, Limpopo

MSCAECDepartment of Agricultural Economics and Agribusines

Sources of rust resistant germplasm and inheritance of rust reaction and hybrid plant abnormalities in common bean

Bean rust, caused by the fungal pathogen Uromyces appendiculatus (Pers.) Unger var. appendiculatus is a major disease limiting common bean (Phaseolus vulgaris L.) yield and quality worldwide. Bean germplasm of wide origins was evaluated for reaction to a diverse collection of rust races/pathotypes. The presence or absence of hairs on the abaxial leaf surface of the bean germplasm was also recorded. Bean rust differential cultivars/lines, used for rust race identification, had specific resistance (SR) to many of the races/pathotypes tested. Bean germplasm from Malawi lacked broad SR but had adult plant resistance (APR). Many of the Malawian germplasm with APR were glabrous and no association was observed between APR and abaxial leaf pubescence (ALP). Inheritance of SR, APR, ALP, flower and stem color and their associations were determined in recombinant inbred lines (RILs) from six common bean crosses. Inheritance of SR to rust was primarily controlled by single major genes. Inheritance of APR also was governed by a single major gene. An epistatic interaction was detected between SR and APR such that APR to a specific race/pathotype cannot be measured in a plant with SR to the same race/pathotype. ALP was controlled by a single major gene. Flower color (FC) and Stem color (SC) were governed by two different major genes. No association or linkage was detected between SR or APR and ALP, FC or SC. Inheritance of three hybrid plant abnormalities (HPA), plant crippling (C), plant lethality (L), and leaf variegation (V) and SR to rust was studied in F\sb2 and F\sb3 progenies derived from some common bean crosses. A single dominant gene controlled SR in cross \u27PC-50\u27 x Chichara 83-109. Duplicate recessive genes controlled C in the same cross. Inheritance of C and L were each determined by the interaction of two different recessive genes. No association was detected between SR and the three HPA traits, FC, SC, L or V

An Insight of Parasitic Weeds in Africa and Scientific Developments: A Review

Parasitic weeds are a major threat to food security in Africa and control measures mostly done by smallholder farmers are not effective in eradicating the parasites. This results in a yield loss up to 100%. Parasitic weeds comprise Alectra vogelii, Striga spp., Orobanche spp., Rafflesia spp., and Phoradendron spp. Parasitic attachment is successful when three necessary conditions have been fulfilled namely the compatible host, suitable environment, and parasitic weed. These species parasite plant species through special attachment features such as modified leaves, suckers, haustoria, or modified roots. In Africa, the variability of parasitic weeds is largely driven by environmental factors such as temperature, rainfall, soil type, and crop husbandry practices. Warmer temperatures create more hospitable conditions for certain parasitic weeds, and allowing them to spread to new areas. Parasitic weed control is vital for effective crop production and the control strategies can be achieved through integrated weed control method that embraces mechanical, cultural, chemical, and biological methods. However, the most effective and crucial method is the cultivation of resistant varieties that provide long-term protection against parasitic weeds. Studies have been done on host-parasite attachment where dodder can send out new roots to infected neighbouring plants and spread their parasitic behaviour. More insight and knowledge should offer new goals for control within the life cycle of the parasitic weeds and their metabolic activities. Lastly, disciplines such as agronomy, plant breeding, nutrition, economics, and IT should play their roles effectively in combating parasitic weeds

Unravelling the impact of soil types on zinc, iron, and selenium concentrations in grains and straw of wheat/Amblyopyrum muticum and wheat/Triticum urartu doubled haploid lines

The concentration of mineral nutrients in plants is associated with bioavailabilities of soil mineral nutrients, which are regulated by various soil physio-chemical properties. A pot experiment was conducted to investigate the effects of soil type on grain and straw zinc (Zn), iron (Fe) and selenium (Se) concentrations of wheat/Amblyopyrum muticum and wheat/Triticum urartu doubled haploid lines. A set of 42 treatments in a factorial combination with 21 genotypes and two soil types collected from Ngabu and Chitedze Research Stations in Malawi was laid in a randomised complete block design (RCBD) in three replicates. Pre-experiment soil Zn and Fe were extracted using DTPA extraction method followed by analysis with inductively coupled plasma-mass spectrometry (ICP-MS). Aqua-regia hotplate acid digestion was used to extract soil Se and analysis was done using ICPM-MS. Grain and straw samples were digested using nitric acid digestion (HNO3) and analysed using ICP-MS. Soil analysis results showed that the two soils had the same textural class (Sandy clay loam), but different mineral concentrations, pH levels and percentage organic matter. Analysis of variance revealed a ~two-fold higher Zn concentration in grains grown in low pH, high Zn soils (Chitedze soils) compared to grains grown in high pH, low Zn soils (Ngabu soils). Variation in grain Zn concentration was associated with the genotypes (p = 0002), soil type (p = <0.0001), and their interaction (p = 0.035). Grain Fe was 1.3-fold higher in low pH than in high pH soils, and it was influenced by genotypes (p = < 0.0001) and soil type (p = <0.0001). Grain Se was highly associated with soil type (p = <0.0001), and it was 30-fold higher in high pH than in low pH soils. Straw Zn was generally higher in plants grown in Chitedze soils than Ngabu soils, whilst straw Se was higher in plants grown in Ngabu soils than Chitedze soils. The findings demonstrate the significance of soil physio-chemical properties for mineral accumulation and distribution to plant parts, thus informing future breeding programs on important considerations on crop genetic biofortification with the three mineral elements