Highlights• Mechanical harvesting removes foliage indiscriminately and decreases tea yield.• Desirable shoot number and mass are reduced under mechanical harvesting.• The maintenance layer is depleted in mechanically harvested bushes.• There are a greater number of strong sinks in mechanically harvested bushes.• Sink/source dynamics altered by mechanical harvesting. AbstractHigh labour costs and shortages and the cost of production has resulted in tea (Camellia sinensis (L) O. Kuntze) industries in central and southern Africa becoming unprofitable. This has led to the full mechanization of shoot harvesting, however, a reduction in yield has been observed with mechanical harvesting. It was hypothesized that the decline in yield as a result of mechanical harvesting is a result of the indiscriminate harvesting of shoots which leads to a change in sink/source and radiation interception dynamics within the canopy. As a result whole plant photosynthesis is impacted; which ultimately impacts tea bush productivity. Studies conducted at 2 Tingamira estate, Chipinge, Zimbabwe showed significant yield differences between hand plucking and machine harvesting treatments, with higher yields under hand plucking across all seasons (43 945 kg green leaf ha ) and ride-on machines (36 268 kg green leaf ha -1 ) (p<0.05). This reduction in yield was associated with a decrease in both the number and mass of desirable shoots over each season. The cause of this change was largely attributed to the indiscriminate removal of foliage by the machines which resulted in the proliferation of immature shoots, with an associated increase in sink strength and competition for available photo-assimilates. In addition, the depletion of the maintenance layer in mechanically harvested bushes, as indicated by reduced fractional interception of photosynthetically active radiation in the top 10 cm in these bushes and reduced photosynthetic rates in these bushes, suggests that these bushes were also source limited, as compared to hand plucked bushes. Therefore the changes in tea bush architecture, as a result of mechanical harvesting, resulted in changes in sink/source dynamics which led to a proliferation of immature shoots which competed for limited photo-assimilates.

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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<0.05 level, only significant on household size.