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Daily oral pre-exposure prophylaxis (PrEP) offers effective HIV prevention. In South Africa, PrEP is publicly available, but use among young women remains low. We explored young women's perceptions of PrEP to inform a gender-focused intervention to promote PrEP uptake. Six focus group discussions and eight in-depth interviews exploring perceptions of PrEP were conducted with forty-six women not using PrEP, ages 18–25, from central Durban. Data were thematically analyzed using a team-based consensus approach. The study was conducted among likely PrEP users: women were highly-educated, with 84.8% enrolled in post-secondary education. Qualitative data revealed intersecting social stigmas related to HIV and women's sexuality. Women feared that daily PrEP pills would be confused with anti-retroviral treatment, creating vulnerability to misplaced HIV stigma. Women also anticipated that taking PrEP could expose them to assumptions of promiscuity from the community. To address these anticipated community-level reactions, women suggested community-facing interventions to reduce the burden on young women considering PrEP. Concerns around PrEP use in this group of urban, educated women reflects layered stigmas that may inhibit future PrEP use. Stigma-reducing strategies, such as media campaigns and educational interventions directed at communities who could benefit from PrEP, should re-frame PrEP as an empowering and responsible choice for young women. [ABSTRACT FROM AUTHOR]

The exotic Tamarix species, T. ramosissima and T. chinensis, were introduced into South Africa in the early 1900s reportedly either for ornamental or soil wind erosion control purposes in the mines. They are, however, currently invading several riparian ecosystems in the country and threatening its biodiversity and proper functioning. The objective of this study was to assess the effects of the exotic Tamarix species on the soil physicochemical properties vis-à-vis the indigenous Tamarix at the Leeu River in the Western Cape Province, of South Africa where they are purvasive. Three transects were laid from the riverbank towards the outer land, where the exotic followed by the native Tamarix species predominantly occurred. Soil was sampled from three points per transect and three soil depths (0–10, 10–20 and 20–30 cm) per point in winter and summer to determine selected soil physicochemical properties. The results showed that total nitrogen (TN), total carbon (TC), Sodium (Na), Potassium (K) and Magnesium (Mg) concentrations under the native and exotic Tamarix species were significantly higher than those in the open land without Tamarix species. The salinity under the native and exotic Tamarix species was greater (P < 0.05) in the topsoils (0–10 cm) than in the deeper soils (20–30 cm) with 5.05 mS cm−1 and 4.73 mS cm−1, respectively. Soil electrical conductivity (EC) was higher (P < 0.05) during the winter season under the exotic Tamarix species (5.05 mS cm−1) followed by the native species (4.73 mS cm−1) and it was the lowest in the control (0.16 mS cm−1) at 0–10 cm soil depth. Similarly, sodium and sodium absorption ratios (SAR) under the native and exotic Tamarix species were significantly greater than those in the control. The highest levels (P < 0.05) of TC were recorded at the topsoil (0–10 cm soil depth) under the exotic Tamarix species (1.17%), followed by the native Tamarix (1.07%) with the control recording the lowest (0.53%). There were no significant differences (P < 0.05) in K, TC, TN and SOC concentrations at lower soil depths (20–30 cm). The soil texture was significantly affected by the Tamarix species. The soil bulk density was lower under the exotic Tamarix followed by native Tamarix species than the control soils. The soil volumetric water content was higher under the exotic Tamarix species compared to the control. This study concludes that the invasion of the exotic and native Tamarix species altered the soil properties underneath and created conducive soil conditions for their predominance. [ABSTRACT FROM AUTHOR]

Conservation agriculture (CA) is believed to contribute to sustainable crop production. However, there are contrasting reports on its short-term effects on soil properties. An experiment was conducted to determine the effects of CA on bulk density (BD), porosity, mean weight diameter (MWD) and penetration resistance (PR) in a semiarid province of South Africa (SA). A split–split–plot design was used; the main treatment factor was allocated to tillage [(Conventional Tillage (CT) and No-Till (NT)], sub-factor of crop rotation [(Maize-Fallow- Maize (MFM), Maize–Oat–Maize (MOM and Maize–Vetch–Maize (MVM))] and sub-sub factor of residue management [(retention (R+); removal (R-) and biochar (B)]. No-tillage, significantly increased soil organic carbon (SOC) compared to CT at the 0–5 cm depth. Tillage, crop rotation and residue management significantly (P < 0.01) affected MWD at the 0–5 cm depth, but not (p > 0.05) on BD, porosity and PR. The lack of significant differences, in both NT and CT plots, between biochar applications and residue retention with respect to BD, MWD across seasons and PR, also show that biochar can potentially be used as a crop residue strategy in a CA system. However, there is a need to further tests and also explore the biochar crop residue retention combinations. [ABSTRACT FROM AUTHOR]

Objectives: To explore women’s willingness to consider using pre-exposure prophylaxis for HIV prevention in the context of gendered relationship dynamics, in Durban, South Africa. Methods: As formative research prior to development of a gender-informed intervention to introduce pre-exposure prophylaxis to young, urban, educated women, we conducted six focus-group discussions and eight in-depth interviews with 46 women ages 18–25 years, who were not current pre-exposure prophylaxis users. Women were recruited from clinic and community settings using a criterion-based snowball sampling technique. Qualitative data were coded and analyzed thematically, with a team-based consensus approach for final coding, analytical decisions, and data interpretation. Results: Women clearly understood the benefits of pre-exposure prophylaxis for themselves and their partners, focusing on promoting health and their right to protect themselves from HIV infection. At the same time, and in accordance with findings from other studies, women were realistic about the concerns that would arise among male partners, including disapproval, loss of trust, possible loss of the relationship, and in some instances, the potential for violence, if they were to propose pre-exposure prophylaxis use. To resolve this tension, some women advocated for covert use as the best option for themselves and others argued for disclosure, proposing various approaches to working with partners to adopt pre-exposure prophylaxis. The suggestion that both partners use pre-exposure prophylaxis was made repeatedly. Thus, women sought to avoid discussions of trust or lack of trust and a partner’s possible infidelities, choosing instead to focus on preserving or even building a relationship through suggesting pre-exposure prophylaxis use. Conclusion: Women offered diverse narratives on agency and constraint in relation to choosing pre-exposure prophylaxis as a future prevention strategy, as well as ways to engage with their male partners about pre-exposure prophylaxis. These findings speak to the need for interventions to bolster women’s confidence, sense of empowerment, and their communication and decision-making skills for successful HIV prevention. [ABSTRACT FROM AUTHOR]

Effect of canopy position on rind biochemical properties of 'Marsh' grapefruit during postharvest non-chilling cold storage was evaluated on fruit harvested from different orchard locations. Inside canopy (IC) and outside canopy (OC) fruits were harvested at commercial maturity from two commercial farms located at KwaZulu-Natal (KZN) and Limpopo (LMP), South Africa, during two seasons. Rind biochemical analyses including color indices, total phenolic concentration, and sugars were performed on harvested grapefruit after Weeks 0, 3, 6, and 9 of cold storage at 7.5 ± 0.5°C. Canopy position showed a high significant (p <.001) effect on rind biochemicals while significant (p <.05) influence of orchard locations was observed on the same parameters. Reducing sugars were more concentrated in IC fruit harvested from both orchard location than OC fruit at Weeks 0 and 3, but inverse results occurred at Weeks 6 and 9. Orchard location significantly (p <.001) influenced vitamin C (14.4, 14.2, 14.4, 14.8 g kg−1) and (12.3, 16.1, 15.9, 14.6 g kg−1) of fruit rind at Weeks 0, 3, 6, and 9 from KZN and LMP, respectively. This study revealed that canopy position can influence rind biochemical properties of 'Marsh' grapefruit during non-chilling postharvest cold storage. However, further studies are required to formulate and provide the citrus industries with adequate advice. [ABSTRACT FROM AUTHOR]

This study investigated, soil salinity and moisture content under the exotic Tamarix in the Olifants River, South Africa, where they predominantly occur. Soil electro-conductivity (EC) was mapped using the electromagnetic induction (EMI) device (EM38 sensor), in three transects laid along the river from as close to the water source outward towards the bank of the River at 50 m apart. This was supported by three soil EC and moisture measurements from each of the three transects at a soil depth of 0–100 cm at intervals of 10 cm using soil EC meter and Amplitude Domain Reflectometry (ADR) sensor, respectively. The highest salt concertation (3,000 mS/m or 19,500 ppm) was found at a depth of 30–40 cm under the dense Tamarix species. The highest soil moisture (20–40%) was also found at the same depth under the Tamarix, suggesting a hydraulic lift of water to the top 30–40 cm, where the Tamarix fine roots for water absorption occur. It also confirms that the distance from water point and Tamarix plant density affect salt leaching depth and amount of litter decomposition, respectively, which is the main source of salt deposition in soil. [ABSTRACT FROM AUTHOR]

Despite a decade of advancing HIV/AIDS treatment policy in South Africa, 20% of people living with HIV (PLHIV) eligible for antiretroviral treatment (ART) remain untreated. To inform universal test and treat (UTT) implementation in South Africa, this analysis describes the rate, timeliness and determinants of ART initiation among newly diagnosed PLHIV. This analysis used routine data from 35 purposively selected primary clinics in three high HIV-burden districts of South Africa from June 1, 2014 to March 31, 2015. Kaplan-Meier survival curves estimated the rate of ART initiation. We identified predictors of ART initiation rate and timely initiation (within 14 days of eligibility determination) using Cox proportional hazards and multivariable logistic regression models in Stata 14.1. Based on national guidelines, 6826 patients were eligible for ART initiation. Under half of men and non-pregnant women were initiated on ART within 14 days (men: 39.7.0%, 95% CI 37.7-41.9; women: 39.9%, 95% CI 38.1-41.7). Pregnant women initiated at a faster rate (within 14 days: 87.6%, 86.1-89.0). ART initiation and timeliness varied significantly by district, facility location, and age, with little to no variation by World Health Organization stage, or CD4 count. Men and non-pregnant women newly diagnosed with HIV who are eligible for ART in South Africa show suboptimal timeliness of ART initiation. If treatment initiation performance is not improved, UTT implementation will be challenging among men and non-pregnant women. UTT programming should be tailored to district and location categories to address contextual differences influencing treatment initiation. [ABSTRACT FROM AUTHOR]

A better understanding of the post-harvest physiology of avocado (Persea americana Mill.) fruit is required to improve the post-harvest management of the crop. Two heptoses, D-mannoheptulose and perseitol, occur in unusually high concentrations in avocado tissues and are thought to be important in fruit ripening. We determined changes in the concentrations and relationships between individual sugars, total soluble proteins, and oil during fruit ripening. 'Hass' fruit were harvested from cool and warm sub-tropical areas in South Africa three-times during a single season. Dry matter increased during the season at both locations. For fruit from the cool sub-tropical climate, D-mannoheptulose and perseitol concentrations declined rapidly from 15.9 mg g-1 dry weight (DW) and 7.9 mg g--1 DW to 2.1 mg g-1 DW and 0.6 mg g-1 DW, respectively, 13 d after harvest. Overall concentrations of glucose and fructose were negligible at harvest and increased to 1.4 mg g 1 DW and 0.8 mg g-1 DW, respectively, during ripening. The concentration of glucose in fast-ripening fruit increased 3 d prior to increasing in slow-ripening fruit. The concentration of sucrose was intermediate (2.8 - 4.5 mg gq DW) and was variable during ripening. The concentration of total soluble proteins increased during ripening from 17.8 mg g-1 DW to 34.8 mg g-i DW, whereas the concentration of oil was fairly stable during ripening, and varied from 24.8 - 36.7% DW, depending on fruit maturity. It is suggested that the heptose pool is an important source of carbon and/or energy in avocado fruit. The low concentrations of these sugars and the rapid decline in their levels, post-harvest, indicate that optimal post-harvest management, especially cold storage and ripening temperature regimes, is necessary to reduce the risk of post-harvest disorders and to ensure a consistent supply of high-quality avocado fruit. [ABSTRACT FROM AUTHOR]

Understanding the impacts of agricultural practices on carbon stocks and CO2 emission is imperative in order to recommend low emission strategies. The objective of this study was to investigate the effects of tillage, crop rotation, and residue management on soil CO2 fluxes, carbon stock, soil temperature, and moisture in the semi-arid conditions in the Eastern Cape of South Africa. The field trial was laid out as a split-split-plot design replicated three times. The main plots were tillage viz conventional tillage (CT) and no-till (NT). The sub-plots were allocated to crop rotations viz maize–fallow–maize (MFM), maize–oat–maize (MOM), and maize–vetch–maize (MVM). Crop residue management was in the sub-sub plots, viz retention (R+), removal (R−), and biochar (B). There were no significant interactions (p > 0.05) with respect to the cumulative CO2 fluxes, soil moisture, and soil temperature. Crop residue retention significantly increased the soil moisture content relative to residue removal, but was not different to biochar application. Soil tilling increased the CO2 fluxes by approximately 26.3% relative to the NT. The carbon dioxide fluxes were significantly lower in R− (2.04 µmoL m−2 s−1) relative to the R+ (2.32 µmoL m−2 s−1) and B treatments (2.36 µmoL m−2 s−1). The carbon dioxide fluxes were higher in the summer (October–February) months compared to the winter period (May–July), irrespective of treatment factors. No tillage had a significantly higher carbon stock at the 0-5 cm depth relative to CT. Amending the soils with biochar resulted in significantly lower total carbon stock relative to both R+ and R−. The results of the study show that NT can potentially reduce CO2 fluxes. In the short term, amending soils with biochar did not reduce the CO2 fluxes compared to R+, however the soil moisture increases were comparable. [ABSTRACT FROM AUTHOR]

Conservation agriculture (CA) as a system is still evolving on many of the smallholder farms in sub-Saharan Africa (SSA) and questions on the impact of individual components and pathways toward adoption still require answers. A short-term study was conducted to investigate the effect of tillage, crop rotation, and crop residue management, including maize residue biochar on above ground biomass, cumulative carbon (C) input, soil organic carbon (SOC), and maize grain yield. A split–split plot design was used to evaluate two tillage operations (conventional tillage (CT) and no-till (NT)), three crop rotations (maize–fallow–maize (MFM), maize–oat–maize (MOM), and maize–vetch–maize (MVM)), and three-crop residue management (retention (R+), removal (R−), and biochar (B)). The cumulative above ground biomass produced in the MOM rotation was significantly higher by 78.9% and 88.7% relative to MVM and MFM rotations, respectively. The cumulative C input under residue management treatments ranged from 10.65 to 12.16 Mg ha−1. The highest SOC was observed under R+ (1.10%) followed by B (1.0%) and the lowest was in R− (0.96%). Crop residue management significantly affected grain yields in 2015/2016 (p < 0.05) and 2016/2017 (p < 0.01) summer seasons. Biochar did not result in an obvious improvement in both C input and crop yield. Smallholder farmers can potentially switch from CT to NT without any significant yield penalty, as well as adopt MOM and R+ practices for increased biomass and C input. [ABSTRACT FROM AUTHOR]

• The germination of cannabis treatments varied with landrace and treatments. • H 2 SO 4 , GA 3 , and KNO 3 enhanced the germination capacity of cannabis landraces. • Control produced vigorous seedlings compared dormancy-breaking pre-treatments. The current study evaluated the effectiveness of different pre-treatments for dormancy breaking and seed germination of five cannabis landraces. These landraces were collected from local growers in three regions of KwaZulu-Natal Province in South Africa, namely, Bergville (B), Hammersdale (H), and Ladysmith (L). Each genotype was assigned an alphabet and number based on where the seed material was collected. The five landraces were as follows, 'B1', 'K1', 'H1', 'L1', and 'L2'. The study was conducted using various pre-treatments, including potassium nitrate (KNO 3), hydrochloric acid (HCL), hot water (HW) at 70 °C, nitric acid (HNO 3), dry prechilling at 10 °C, gibberellic acid (GA 3), sulfuric acid (H 2 SO 4), and water, which served as the control. Before the germination test, the seed viability of cannabis landraces was assessed using the tetrazolium chloride (TCC) test. Afterward, the seeds were germinated in Petri dishes with cotton pads moistened with distilled water for five (5) days. The study was later validated under tunnel conditions. The parameters such as germination percentage, germination rate, seedling length, and seed vigour index of the germinated seeds were then measured. The landraces, dormancy breaking treatments, and their interactions showed significant differences (p < 0.001) in germination percentage, germination rate index, seedling length, and seed vigour index under both laboratory and tunnel conditions. In summary, GA 3 , KNO 3 and prechilling were the most effective pre-treatments to improve the germination and seedling growth of cannabis genotypes and breaking seed dormancy. Therefore, it was concluded that cannabis genotypes had physiological dormancy. [ABSTRACT FROM AUTHOR]

South Africa is rich with a diverse range of leafy vegetables that are rich in nutrients. African leafy vegetables (ALVs) are limited in terms of their commercial production due to lack of production information such as water requirements and yield. The effect of water stress on growth, physiology and yield of ALVs were evaluated under field conditions at the Agricultural Research Council (ARC), Roodeplaat, Pretoria, over two seasons, 2015/2016 and 2016/2017. A randomised complete block design was used with: three water levels [30%, 60% and 100% of crop water requirement (ETc)] and four ALVs (Amaranthus cruentus L., Corchorus olitorius L, and Vigna unguiculata (L.) Walp and Beta vulgaris L.), replicated three times. In A. cruentus , moisture stress (30% ETc) reduced plant height, chlorophyll content index (CCI) as well as yield. In B. vulgaris leaf number, plant height and yield were reduced by water stress. In both A. cruentus and B. vulgaris , yield increased with increase in water application from 30% ETc to 60% ETc and remained the same at 100% ETc. For C. olitorius and V. unguiculata , CCI, plant height and yield were not affected by water stress although stem fresh mass was reduced by water stress in V. unguiculata. Using 60% ETc appears ideal for production of A. cruentus and Beta vulgaris , whereas 30% ETc is recommended for V. unguiculata and C. olitorius. Results of A. cruentus and Beta vulgaris were comparable under similar conditions. V. unguiculata and C. olitorius performed better than Beta vulgaris indicating an opportunity to improve productivity under drought conditions. • Moisture stress reduced plant height, chlorophyll content index (CCI) as well as yield in A. cruentus and B. vulgaris. • For C. olitorius and V. unguiculata , CCI, plant height and yield were not affected by water stress. • Using 60% ETc appears ideal for production of A. cruentus and Beta vulgaris. • 30% ETc is recommended for V. unguiculata and C. olitorius. [ABSTRACT FROM AUTHOR]

• Photosynthetic efficiency of leaves from different positions of avocado trees was assessed. • Outside leaves had higher photosynthetic rate and stomatal conductance. • The high photosynthetic efficiency of outside fruit was linked fruit maturity. • Outside fruit matured earlier with mesocarp DM content of 23.2% compared to 22.3% on inside fruit. Physiological changes associated with leaf chlorophyll fluorescence and gas exchange are the key components towards understanding performance of fruit trees. In this study, the photosynthetic efficiency of leaves from inside and outside canopy positions of avocado trees was assessed during the fruit growing season. The aim was to determine to what extent photosynthesis and gas exchange of the leaves correlates with the position of the leaf inside canopy and outside canopy of an avocado tree, and how does that affect fruit maturity. The study was conducted in a commercial orchard at Everdon Estates in the KwaZulu-Natal, South Africa during 2017/18 season. A total of fifteen 8-year old avocado trees (cv. 'Carmen') were selected in a completely randomised design with three replicates and each replicate consisting of five trees. Data was collected bi-weekly from full bloom to fruit physiological maturity (25% dry matter content). Measured variables included gs, C i, T , A , F 0 , F m , Fv/Fm , ΦPS II , qP, qN, ETR, 1- qP and DM content, were estimated within and outside canopy. Results showed that leaves from the outside position had higher A (22.28 mol CO 2 m−2 s−1) , gs (0.22 mol CO 2 m−2 s−1) , ΦPS II (0.35), and qP (0.57) compared to those on the inside position of the canopy with lower values of 14.19 mol CO 2 m−2 s−1, 0.14 mol CO 2 m−2 s−1, 0.047 and 0.071, for A, gs, ΦPS II and qP respectively. Conversely, Fo', Fm' , Fv', Fv'/Fm' , and 1- qP were about two times higher on the inside canopy than on the outside. The high photosynthetic efficiency of outside fruit was linked fruit maturity with fruit from the outside maturing earlier with an average mesocarp dry matter content of 27.6% compared to 26.5% on fruit from the inside canopy. The findings suggest that the high sunlight interception by leaves from the outside position improved photosynthetic efficiency, increased rate of dry matter accumulation and maturation of avocado fruit. There is a strong sink demand within the outside canopy demanding more carbohydrates, and thus commanding leaves from the outside canopy to photosynthesize more efficiently leading to fast maturity. [ABSTRACT FROM AUTHOR]

The nutrient composition and starch properties of eight potato cultivars (Electra, Fianna, Innovator, Mondial, Navigator, Panamera, Savanna and Sifra) were evaluated, to determine their value to human nutrition and to inform decisions for culinary usage. Potatoes that had been cultivated under the same agronomic conditions were used. The results showed that there were significant differences ( P < 0.05) in the parameters measured. Fianna and Innovator had the highest dry mass of 22 and 21%, respectively, while Electra had the lowest (16%). Innovator, together with Navigator, displayed the highest starch content (17.9% fresh weight [fw]), with the highest proportion of amylose (27.2% dry weight [dw]). However, Fianna and Panamera had the highest protein content (2.87 and 2.53% fw, respectively). Electra had the highest calcium (10.2 g 100 g −1 fw) and iron (2.91 g 100 g −1 fw) content. This represents a contribution of 3 and 32%, respectively, to the population-weighted estimated average dietary requirement of Africa. Innovator also contained the lowest aluminium contribution (12%) to the tolerable weekly intake limit set by the FAO. In addition to low amylose, the starch of Mondial had a high swelling power, oil absorption capacity and gelatinisation enthalpy, and a greater frequency of small-sized granules. [ABSTRACT FROM AUTHOR]