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This study evaluates the importance of wild edible mushrooms as food in three villages of the Binga, Zimbabwe. A purposive sampling method was employed to select three villages from two (Local Government Area) wards, 25 households per each village randomly selected from the total household list provided by the district administration department, with a total of 75 households. An open ended, structured semi structured interview guide was used to provide a preliminary list of wild edible mushrooms in the area and the identification methods used, using seven households from the three villages. Structured, semi-structured and guided forest walks with some of the informants and forest picking observation was carried out with local guide assistants who have the skills of local (Tonga) language and Shona language. An econometric model was used to identify the factors influencing wild edible mushroom consumption in the study area. Descriptive statistics was used to describe the socio-economic characteristics of the respondents. Results from purposive sampling showed that seven ethnospecies of wild edible mushrooms were listed (in Tonga and scientific names in parenthesis: Bakapyapya (Cantharellus spp), Bakayanda (Amanita loosii (zambiana)), Bwabbaya (Termitomyces spp), Indyuu (Termitomyces titanicus), Madongila (Amanita spp), Mbuse (Termitomyces clypeatus), Nowa (Lactarius kabansus) and Indyuu, Madongila, Nowa) and of these three were noted as extinct species (Indyuu, Madongila, Nowa). About 43% of the participants consumed wild edible mushrooms once every day, 19% twice every day and 14% every second day during the rainy season, underpinning the potential importance of wild edible mushrooms for food security. Around 52% of the participants collected wild edible mushrooms once every day, 28.6% of the every second day while around 16% collected once a week, during the rainy season. Ethnobotanical knowledge of wild edible mushrooms was mainly passed orally from elderly to young people (72.9% of the participants), while 15.7% passed by mothers to their children and 11% learned from female elders to young women and girls. Identification techniques such as texture feeling, colour underneath and on top, breaking and observing milk like liquid oozing out and points of collection were used. Women (21.4%), women accompanied by girl child (24.3%) are especially involved in wild edible mushrooms collection, while a minority 1.4% men, women accompanied by boy child (7.1%) did the collection. The mean monthly income per household is US$108.57, largest in Simandala and lowest in Dumbwe. The average age of the participants is 45.37 years. Of the 70 participants, 61.4 were female and 38.6 were male. Average consumption of wild edible mushrooms per meal per household is 1.436kg. About 95.7% of the participant served wild edible mushrooms as main relish, accompanying the staple. The mostly consumed were Indyuu (Zhouchuru) and Bakayanda (Nhedzi), consumed by 100% of the participants. Linear regression showed that the coefficients were positive and not significant at p

Sources of fertilizer are one of the major factors influencing baby spinach leaf texture, sweetness, bitterness and after-taste. However, the effects of fertilizer sources on baby spinach growth performance and consumer preferences are not known. A survey was carried out at the Seke Teachers’ College (SKC) community, Zimbabwe to determine the consumer preferences on the baby spinach grown on the organic fertilizer (cattle, poultry and goat manures) as well as on control inorganic fertilizers (7% N, 14% P, 7% K). The study used 32 females and 30 males as panellists for sensory evaluations. Organoleptic tests were performed for the baby spinach leaves using a panel of 62 testers. An interval line scale (16 cm long) was used to measure the liking for sweetness, colour, bitterness and after-taste. A 9-point hedonic scale was used to decide the overall preferences. Organoleptic tests showed significant differences (P

Baby spinach is a relatively new crop of commercial significance in South Africa with considerable health attributes. Three parallel trials to investigate its response to nitrogen (N), phosphorus (P), and potassium (K) were conducted. N and P (0, 45, 75, 105, and 120 kg·ha−1) and K (0, 63, 85, 127, and 148 kg·ha−1) treatments were applied to baby spinach in a randomized block design with four replications. After the parallel trial, NPK combination trial was also done. The biomass yield, chlorophyll content, and leaf area index increased significantly with increase in N and P rates; K had no effect on the yield, chlorophyll content, stomatal conductance, and leaf area index. Yield and chlorophyll content peaked at 75 kg·ha−1 of N/P but growth was best optimized at the NPK combination of 45:45:60 kg·ha−1.

Bush tea (Athrixia phylicoides DC.) is an herbal beverage and medicinal plant indigenous to South Africa. This study evaluated the effects of micronutrients on bush tea quality. Treatments consisted of single applications of zinc (Zn), copper (Cu), boron (Bo), iron (Fe), and magnesium (Mg) at three levels (50, 100, and 150 mL/L) and a combination of all micronutrients. A control treatment with no spray was also included. Tea samples were analyzed using head space solid phase microextraction gas chromatography linked to mass spectrometry (HS-SPME-GC-MS). A significant change in the metabolite profile of bush tea was noted. Five major compounds were identified (>80% identification probability) namely alpha-pinene, beta-pinene, myrcene, beta-caryophyllene, and caryophyllene oxide. A linear relationship between percentage leaf tissues and treatment levels of micronutrients in bush tea was also observed. The liquid chromatography linked to mass spectrometry (LC–MS) showed no significant qualitative difference between the control and the micronutrient treatments. There were significant quantitative differences between the control and treatments applied at 50 and 100 mL/L and the combination (B + Zn + Fe + Cu + Mg) applied at 10 and 20 mL/L. The application of micronutrients did have an influence on the metabolite quantities as has been reported with most secondary metabolite fluctuations caused by plant–environment interactions. Altering the micronutrient application may be a possible solution in achieving commercial agricultural production of this medicinal beverage.

Spinacia oleracea L. (baby spinach) is a relatively new leaf vegetable crop in Zimbabwe, so the agronomic performance is unknown. A 3-year field experiment was done at the Seke Teachers College research farm, Zimbabwe. The research evaluated the response of baby spinach to different types of organic manure sources, days after fertilizer application (DAS), and growing season. A 3 × 2 factorial in a completely randomized block design (CRBD) with three replicates was used. Baby spinach cultivar, Dash, was grown on three organic manures (goat applied at 14.894 t ha−1, cattle at 17.789 t ha−1, and poultry at 13.807 t ha−1) in winter 2018, 2019, and 2020. Compound D (7% N, 14% P, and 7% K) at 300 kg ha−1 was included as a control. Crop growth rate, leaf area index, leaf area ratio, net assimilation rate, total dry matter production, and harvest index were measured on 7-day intervals from 14 to 35 days after transplanting. Analysis of variance (ANOVA) to compare the effects of the treatments on the baby spinach growth parameters was done. Significant p < 0. 05 interactions on the type of organic manure × DAS × growing season were observed on all the measured response variables. There were varied effects of organic manures on growth performance at 14 to 28 DAS where poultry manure had higher growth performance compared to cattle and goat manure. Generally, there was a significant p < 0. 05 gradual increase in growth from 14 to 35 DAS on the organic manures and a decline from day 28 to 35 DAS under compound D. Low quality (large C/N) cattle and goat manure had lower effects than high quality (small C/N) poultry manure at early growth stages of the baby spinach. Unlike compound D, organic manure continuously supplied adequate nutrients throughout the life cycle (35 DAS) of the baby spinach.

Baby spinach is a nutritious vegetable rich in phytochemicals and minerals. Cultural practices such as fertilisation have an impact on the nutritional composition of vegetables. Hence, the current study investigated the responses of the chemical composition of baby spinach to nitrogen (N), phosphorus (P) and potassium (K) fertilisation. Three parallel trials for N and P treatments (0, 45, 75, 105 and 120 kg N and P ha−1) and K (0, 60, 85, 100, 125 and 145 kg K ha−1) arranged in a randomised complete block design with four replicates were conducted. Thereafter, a NPK combination trial was also carried out. Nitrogen, P and K increased the concentrations of total phenols, total antioxidants activity, total flavonoids and vitamin C with maximum concentrations observed at 45 kg N ha−1, 45 kg P ha−1 and 85 kg K ha−1. Interactive effects of NPK fertilisers improved the total phenolic content, total antioxidants activity, total flavonoids and vitamin C content at 35 + 35 + 60 kg ha−1 of NPK. Thus, varying fertili...

B spinach (Spinacia oleracea L) is a member of the Amaranthaceae family. Its leaves have a very high respiration rate thus post-harvest quality is affected mostly by tissue decay and the development of off-odours. Thus, this study was conducted to investigate the influence of storage temperature and time on the post-harvest quality of baby spinach. Baby spinach leaves were harvested at 36 days after planting and subsequently stored at 4 C or 22 C for 0, 2, 4, 6, 8, 10 and 12 days. Thereafter the leaves were incubated for 72 hours at 40 C to dry. Minerals, trace elements, total phenols, total carotenoids, flavonoids and antioxidant activities were measured. Composition of magnesium, zinc and iron declined after 8 days of storage at 4 C whilst at 22 C, they declined after 2 days of storage. Magnesium, zinc and iron revealed a similar trend with significantly higher carotenoids found up to 6 days in storage at 4 C whilst at 22 C the carotenoid levels declined after only 2 days. Total phenolic compounds gradually decreased in samples stored at 4 C. However, samples stored at 22 C showed a rapid decrease after 4 days. Both total antioxidant activities and Vitamin C content showed a similar trend with the content remaining constant at 4 C and decreasing after 6 days, whereas the total antioxidant activities and vitamin C for leaves stored at 22 C decreased immediately after 2 days. However, storage time and temperature did not exhibit significant effects on selenium. Results demonstrated that quality of baby spinach deteriorates as storage time and temperature increase.

The grain yield per unit of plant-available nitrogen (N) and sulphur (S) nutrients in the soil is usually low in most crops, including canola. Besides the ability of different crops in utilising nutrients, soil and climatic conditions can also influence uptake and use of major plant nutrients. Hence, to determine the effect of soil and climatic differences on canola agronomic efficiency response to N and S application, a factorial split-plot experiment consisting of three S (0, 15 and 30 kg S ha−1) and five N (0, 30, 60, 90 and 120 kg N ha−1) rates was conducted at selected localities (Altona, Elsenburg, Langgewens, Roodebloem and Welgevallen) in the Western Cape province during the 2009 to 2011 growing seasons. Agronomic efficiencies of N applications were improved if 15 kg S ha−1 was applied, but not with applications of 30 kg S ha−1. Sulphur use efficiency also improved when high N (120 kg N ha−1) was applied. The application of both N and S resulted in higher water use efficiencies at some localities.

Coriander (Coriandrum sativum L.) contains essential oil, and various extracts from the seeds possess anti-bacterial, antioxidant, anti-diabetic, anti-cancerous and anti-mutagenic activities. Field experiments were carried out to study the effect of phosphorus (P) fertilization (0, 12 and 24 kg-ha−1 P) on the seed yield, and volatile oil of Egyptian cultivar of coriander under water stress conditions. The oil was obtained by hydrodistillation extraction method using Clevenger apparatus. Chemical analysis of the oil was done by using gas chromatography and mass spectrometry (GC-MS). Increasing water amounts and P fertilization rates increased plant height, number of branches, number of umbels and seed yield. Essential oil yields increased significantly with increasing water regimes from 50 % to 100 % of ET crop. Irrigation applied at 100 % of crop water need, combined with 24 kg-ha−1 P, gave the best seed and oil yields results. Coriander plants have high water use efficiency (WUE) at 50 % ET crop,...

ObjectiveTo determine the chemical compositions and evaluate the antimicrobial activity of bush tea (Athrixia phylicoides DC.), special tea (Monsonia burkeana) and synergy (combination of bush tea and special tea).MethodsTotal polyphenols were determined using the methods reported by Singleton and Rossi (1965) and modified by Waterman and Mole (1994). Tannins were determined using vanillin HCL methods described by Prince et al. (1978). Total antioxidants were determined using the methods described by Awika et al. (2004). The micro dilution technique using 96-well micro-plates, as described by Eloff (1998) was used to obtain the minimum inhibition concentration (MIC) and minimum microbicidal concentration (MMC) values of the ethanol extracts against the microorganisms under study. The microbes strain used was Gram negative bacteria such as Escherichia coli, Klebsiella oxytoca, Proteus vulgaris, Serratia marcescens, Salmonella typhi, Klebsiella pneumonia; Gram positive bacteria such as Bacillus cereus, Staphylococcus aureus and a fungus Candida albicans.ResultsThe results demonstrated that special tea contains significantly higher content of total polyphenols (8.34 mg/100 g) and total antioxidant (0.83 mg/100 g) as compared to bush tea [total polyphenols (6.41 mg/100g) and total antioxidant (0.63 mg/100g)] and combination of bush tea and special tea [total polyphenols (6.42 mg/100 g) and total antioxidant (0.64 mg/100 g)]. There was no significant difference in tannins between bush tea, special tea and synergy. The results of antimicrobial activity (MIC and MMC) demonstrated that the ethanol extracts of bush tea, special tea and synergy possessed antimicrobial activity against all microorganisms at different zones. The MIC of bush tea ranged from 1.56 to 12.50 mg/mL while the MMC ranged from 0.78 to 12.50 mg/mL. Special tea's MIC ranged from 0.39 to 12.50 mg/mL while the MMC ranged from 0.01 to 12.50 mg/mL. The MIC of synergy ranged from 3.13 to 12.50 mg/mL while the MMC ranged from 3.13 to 12.50 mg/mL without positive synergistic effect recorded.ConclusionsBoth bush and special tea contain total polyphenols, total antioxidants and tannins with special tea containing a significantly higher total polyphenols and total antioxidant as compared to bush tea and synergy. Bush tea, special tea and synergy possess antimicrobial activity at various degrees.

Soil pH and nutrient contents influence the uptake and utilization of nutrients required for plant growth. Soil characteristics in the canola-growing areas of the Western Cape Province of South Africa are often very variable. Hence, the major aim of this research was to determine the effects of soil and climatic differences as experienced at different localities on macro- and micronutrient contents and uptake in canola plants fertilized with different nitrogen (N) and sulfur (S) application rates. Plants fertilized with 0, 15, and 30 kg S ha−1 in combination with N rates of 0 and 90 kg ha−1 were sampled at 90 days after planting (DAP) (flowering stage) at Altona, Elsenburg, Langgewens, Roodebloem, and Welgevallen localities in the Western Cape during 2009 2010, and 2011. Nutrient content in canola plants were affected by locality and interactions between locality and N application rates. Sulfur content within the plants remained less than the sufficient quantity of 0.5%, and a dilution effect on elemental...

On average low grain yields of less than 1.5 t ha-1 are obtained with canola in the Western Cape province of South Africa. Injudicious use of fertiliser has been suggested as a major cause, hence the study was done to determine the effect of soil and climatic conditions, as experienced at different localities, on grain yield and quality response of canola to nitrogen (N) and sulphur (S) applications in a three-year study. Treatments consisted of five N (0, 30, 60, 90 and 120 kg N ha-1) and three S (0, 15 and 30 kg S ha-1) rates laid out in a randomised complete block design with a factorial split-plot arrangement. The study showed that the effect of N supply increased with S supply and was greater in high rainfall areas and seasons than in drier conditions. Low rainfall during flowering and podding may limit yield responses to N applications, with applications of 120 kg N ha-1 and 15–30 kg S ha-1 needed in high rainfall areas to obtain yields of more than 2.0 t ha-1. Application of S also improves the oil...

Fruits have abundant phytochemicals that contribute as bioactive molecules with ability to lower incidence of diseases. Mangoes are rich in polyphenols and antioxidants. In this study, peels of six selected mango cultivars (Tommy Atkins, Peach, Saber, Sunshine, Keitt and Vhavenda) were treated with sulphur dioxide solutions (0, 10, 20, 50, 100, 150, 200, 250 and 300 ppm) as preservative of phytochemicals and antioxidants capacity. Regardless of cultivar, sulphur concentration had effect on composition of polyphenols and antioxidant capacity of mango peels, reaching a plateau at 50 ppm. Vhavenda cultivar has significantly highest polyphenols and antioxidant capacity than the other cultivars evaluated. This study reveals that mango peels are a prospective source of natural antioxidants as they constitute significantly higher total antioxidant capacity and phenolic content.Keywords: Antioxidants, mango cultivars, peels, phytochemicals, sulphur.African Journal of Biotechnology Vol. 12(41), pp. 6007-6012

Pruning is an essential agronomic practice and it has been shown to be the most important operation, next to plucking, which directly determines the productivity and quality of tea bushes. In tea, pruning helps stimulate vegetative growth and prevent reproductive growth phase. In addition, pruning leads to enhanced branching and hence it rejuvenates the tea plants resulting in a greater number of tender leaves for healthier and better quality tea plants. This review illustrates the effects of pruning on yield and quality of herbal teas. Through the review, it is worthy investigating the effect of pruning and pruning time on yield and chemical compositions. It will also shed light on the effects of resting period before pruning. Lastly the review focuses on the effect of different pruning intervals on productivity of tea. Key words: Carbohydrate dynamics, bush tea, productivity, pruning, quality.

Smallholder farmers are major contributors of horticultural produce. Women’s contribution is noteworthy. Meeting market demand on time and avoiding market ‘floods’ is a challenge among communal farmers, leading to post harvest losses partly due to lack of information and uninformed decision making. Mobile phones have potential to connect farmers to markets, close the information gap and enable informed decisions. Currently most farmers target a few markets leading to market ‘floods’, low prices and fresh produce deterioration while some potential markets remain untapped. A survey conducted in 2015 covering 131 farmers in Svosve-Wenimbi, Marondera district of Mashonaland East province in Zimbabwe evaluated mobile phone ownership and use in farming; and its potential in transforming production and marketing. High literacy and mobile phone ownership of 95.32% and 94.45% respectively was reported, with 16% already accessing advisory services over mobile phone. 51.1% utilised various mobile phone services including accessing market information on inputs and produce, advisory services, weather data, mobile phone money transfers for transaction and crop insurance. By using mobile phones farmers made informed decisions and saved time and transport cost. Mobile phone ICT can promote better production, marketing, food security and livelihoods and more farmers may adopt the technology. Keywords: small holder agriculture, marketing, mobile phones, women, Zimbabwe, extension implications

Various crop residues can be used in producing Oyster mushrooms either as main substrates or in combinations with supplements. Yield response is determined by the type of crop residue and production practice used. Two factorial experiments were performed to evaluate the mycelium vigor and biological efficiency (BE) of Oyster mushroom produced on composted cotton residues, maize stover and wheat straw substrates enriched with either sunflower seed cake or pigeon pea hulls. Yield improvement were observed in both pigeon pea and sunflower seed cake supplemented treatments with the highest mycelium vigor (91.65%) and biological efficiencies (106.65%) observed, whilst the control treatments had 71.1% mycelium vigor and 27.6% biological efficiency. Mycelium growth and biological efficiency were satisfactory with the use of either supplement. Contribution of flushes to total yield was improved with addition of either supplement with up to 70% contribution in pigeon pea supplemented cotton residues. Supplements were equally effective for improving the performance of Oyster mushroom in almost all the substrates used. Composting of the substrates was beneficial in cotton residues and wheat straw substrates with biological efficiency of 145.7 and 28.2% respectively compared to their controls (32.3 and 5.3 respectively). It was concluded that both supplement can be used to enhance production and composting was not beneficial with maize stover. Keywords : biological efficiency, compost, mycelium vigor, pigeon pea, sunflower seed cake International Journal of Biological and Chemical Sciences Vol. 2 (1) 2008 pp. 72-80

Low mushroom yields are observed when non-supplemented substrates are used for production. The experiments were carried out to evaluate potential benefits of organic supplements in cotton residues, maize stover and wheat straw substrates used for cultivation of oyster mushroom. Mixed formulations at various doses of 0, 4, 8 and 14 % sunflower seed cake supplement levels were autoclaved before inoculation with P. ostreatus spawn. Duration of developmental stages, mycelium vigour and yield of oyster mushroom on substrates formulations were evaluated. The mycelium vigour significantly increased (P International Journal of Biological & Chemical Sciences Vol. 1 (2) 2007: pp. 108-120