Storage Temperature Influences Postharvest Quality of Wild Plum (Ximmenia Americana L.) Fruit

Wild plum has many medicinal, therapeutic and nutritive uses, but its fruits are collected in the wild and less researched. The aim of this study was to evaluate the effects of storage tem­perature on postharvest fruit quality of wild plum. The fruits of wild plum were subjected to different storage treatments at 0, 5, 10 and 15 ± 1°C in a completely randomized design. The results showed that as storage temperature decreased below 15°C, the incidence and severity of chilling injury significantly (p<0.05) increased. As storage temperature increased from 0 to 15°C fruit titratable acidity (TTA) and vitamin C content significantly (p< 0.05) decreased, but juice pH, soluble solids content (SSC) and weight loss significantly (p< 0.05) increased. The decrease in TTA and vitamin C content, and increase in SSC and juice pH was attributed to fruit ripening. The increase in fruit weight loss was attributed to higher transpiration and respiration. It was concluded that to extend the storage-life and marketing period of wild plum fruits, the fruits should be stored at 15°C and 90-95% RH. Keywords: Ximenia americana, Chilling injury and incidence, Vitamin C, Soluble solids content, Acidit

Effect of accel on the vase life and post harvest quality of alstroemeria (alstroemeria aurantiaca l.) cut flowers

Freshly cut flowering stems of Alstroemeria ‘Yellow King’ and ‘Marina’ were placed in glass jars containing solutions of Accel at 0, 25, 50, 75 and 100 mg/litre BA equivalent and arranged in a completely randomised design with 3 replicates. The effect of Accel on the vase life and qualityof Alstroemeria was investigated. Flowers held in Accel at 25 or 50 mg/litre BA equivalent consistently increased the number of days to full opening of primary florets and delayed the onset of flower senescence as measured by days to 50 % petal fall and days to 50 % leaf yellowing. Accel at 25mg/litre BA equivalent significantly increased the leaf nitrogen and chlorophyll content of Alstroemeria cut flowers. High Accel concentrations of 50, 75 and 100 mg/litre BA equivalent reduced significantly the leaf water content of Alstroemeria cut flowers. Accel at 75 and 100 mg/litre BA equivalentincreased leaf dry weight of Alstroemeria cut flowers. Our results indicate that Accel at 25 mg/litre BA equivalent has the potential to be used as a commercial cut flower preservative solution for delaying flower senescence, prolonging the vase life and enhancing post harvest quality of Alstroemeria cut flower

Effect of accel, sucrose and silver thiosulphate on substrate utilization in cut tuberose (Polianthes tuberosa L.) flowers

This study was undertaken to investigate the effect of Accel™, sucrose and silver thiosulphate (STS) on the dry weight, accumulation of sucrose and reducing sugars in cut tuberose (Polianthes tuberosa L) petals at various positions along the spike. Cut stems of Tuberose were held in optimum treatments that prolonged their vase life (Hutchinson et al., 2003): continuous holding in 25 mg/L BA equivalent of Accel; pulsing in 20% sucrose for 24 hrs and subsequently holding in either deionized water (DIW) or in 25 mg/L BA; pulsing in 2 mM STS for 1 hr and subsequent holding in DIW. The middle and bottom florets of cut flowers held in DIW were heavier than the top florets. Pulsing tuberose cut flowers in sucrose or in STS improved the dry weights of the middle and bottom florets in the 1st 3 days but up to 6 days of top florets. Florets of cut flowers pulsed in sucrose and subsequently held in Accel were heavier than those subsequently held in DIW or those held continuously in Accel. Sucrose, STS and Accel increased floret opening but had varied influence on the accumulation of sucrose and reducing sugars in petals of florets along the spike. Cut tuberose stems pulsed in sucrose and subsequently held in either DIW or 25 mg/L BA equivalent of Accel accumulated the largest amounts of sucrose and reducing sugars. Pulsing cut tuberose flowers in 10% sucrose and subsequently holding them in Accel or DIW or pulsing in STS, while having no influence on sucrose levels in bottom florets, significantly increased levels in top florets for the 1st 3 days before a sharp decline in petals pulsed in sucrose. The main difference was that while most of the sucrose accumulated in the middle florets, reducing sugars was concentrated on the bottom florets along the spike. Unexpectedly, pulsing stems in STS or holding them in Accel had no significant influence on levels of sucrose or reducing sugars within the 9 days of testing even though most florets had opened by this time. The results of the present study suggest that while sucrose had a direct influence on accumulating of sucrose and reducing sugars in florets, Accel and STS improved vase life and floret opening in cut tuberose stems either indirectly through substrate mobilization and increased metabolism or may have played another different role other than substrate mobilization

The impact of South African supermarkets on agricultural and industrial development in the Southern African Development Community

Supermarkets have become important in food retail in both developed and developing countries. Supermarkets in developed countries are expanding to developing countries such as Latin America and Asia resulting in transformation of the agro-food systems. As elsewhere in the world, supermarkets are also expanding rapidly in Africa. The growth and expansion of supermarkets is mainly spearheaded by South African supermarkets and has been facilitated by trade liberalization, increased economic growth, positive political changes, regional integration arrangements, increased urbanisation, increased per capita income and middle class population groups and liberalization of foreign direct investment. The increased foreign direct investment (FDI) by South African supermarkets into SADC and the rest of Africa may be impacting on firms, households and the economy in the host nations in various ways. As much as the FDI by South African firms bring the much-needed capital for development, the impact of South Africa supermarkets in SADC and the rest of Africa is least understood. The impact of the expansion of South African supermarkets in the retail sector in other African countries has not been elucidated. Therefore, the objective of this study was to determine the impact of supermarkets on agricultural and industrial (mainly the food processing and manufacturing sector) development in SADC by examining their sourcing and procurement practices. From the identified gaps in literature the study attempts to answer the following questions: what is the extent of growth and expansion of South African supermarkets in case study countries; what are the nature of sourcing and procurement practices and the factors influencing the choice of procurement systems; what are the impacts of these sourcing and procurement practices on farmers and food processors in case-study countries and do farmers gain by participating in the supermarkets FFV supply chain in case-study countries. A case study of three countries (Botswana, Namibia and Zambia) and two supply chains were studied. The study used qualitative and quantitative methods in collecting data in order to elucidate the impacts of these supermarkets on agricultural and industrial (food processing) development in the case study countries. A survey of South African and local chain supermarkets, local shops, food processors, small-scale farmers supplying fresh fruit and vegetables (FFV) to chain supermarkets and the traditional FFV markets was undertaken in the case-study countries in 2004, 2005 and 2007 using questionnaires and checklists. The survey data were augmented with key informant and focus group discussions and secondary data. The analytical methods used included descriptive analysis, non-parametric statistics and a two-step treatment regression analysis model. The conceptual framework for analysing the sourcing/procurement practices of supermarkets and a model to show how impacts in host countries could occur as a result of sourcing decisions were developed and used in the study. The results of the survey of products sold in supermarkets and local shops showed that 80% of all processed food products are sourced from South Africa. About 100% of temperate fruit and 70-100% tropical fruit are sourced from South Africa in the casestudy countries. About 80% of fresh vegetables are sourced from farmers in Zambia and about 80 % are sourced from South Africa for Botswana and Namibia. The results also revealed that supermarkets used a mixture of procurement systems for FFV and processed food products. These systems included use of specialised sourcing and procurement companies; direct delivery of FFV to individual supermarket stores; specialised FFV wholesalers; distribution centres; outsourcing. Using the structured questionnaire supermarket managers were asked the criteria used in sourcing the selected products. The results of the parametric analysis of the responses showed that price, volume, quality and trust were the most important attributes considered respectively. In order to estimate the impact of supermarkets on farmers a household survey was carried out using a structured questionnaire. There were noticeable differences in resources between farmers who supply to the supermarkets and those who supply to the traditional markets. Factors that influence small-scale farmers’ participation in the supermarkets supply chain were identified from the results of the estimated probit model. The results of the two-step treatment regression model showed that participation in the supermarkets channel had a positive impact on small-scale farmers’ income. Mean comparison of income between the two groups of farmers showed that farmers who supplied fresh vegetables to chain supermarkets had a significantly higher income compared to those who supplied to traditional markets in Zambia. This finding confirms hypothesis 2 of the study. The study did not explore causality due to insufficient data on lagged assets. Impacts on the food-processing sector were deduced by carrying out a survey of food processing firms in case-study countries. The goal was to determine the type of firms that access supermarkets supply chain for selected products and determine other channels used for marketing of the products. About 75% of firms started their operations in the 1990s. This period also coincided with rapid supermarket expansion in case-study countries. A symbiotic relationship exists between supermarkets and large processing firms in the case-study countries. There was no evidence to show that supermarkets have caused firms to increase in size or that supermarkets prevented entry of agro-processors in the food processing industry. Small-scale processing firms do not access supermarket supply chains in case-study countries and sell their products through the traditional channels such as small shops and wholesales. Various constraints still prohibit smallscale firms from accessing supermarkets such as lack of capital and lack of finances. From the results of the models and focus group discussions the study concluded that small-scale farmers who meet supermarkets sourcing/procurement requirements were able to access the FFV supply chain of the South African chain supermarkets. Those who did not meet the supermarket requirements who are the majority small-scale farmers and food processors were excluded. Those small-scale farmers who were able to supply to supermarkets earned significantly higher income compared to those who supply to the traditional markets. The study also concluded that membership in a farmers organization does not increase the chances of a farmers accessing and supplying to supermarkets. There is need to re-evaluate the farmer organizations that are being formed to ensure that the organizations assist farmers in accessing supermarkets FFV supply chain and marketing of produce in general. The study also concluded that the traditional markets are still important in case-study countries. These markets need to be improved and developed as small-scale farmers and food processors easily assess them. The study recommended that a holistic analysis of supermarket impacts in the region using general equilibrium type of models is needed, ways to ensure small-scale farmers and processors participation in supermarket FFV supply chain should be determined and more research on the practices of supermarkets as oligopsonists in the region should be carried out. The study was able to document the extent of growth and expansion of supermarkets in case-study countries and as such contributed to literature by describing the sourcing and procurement practices and factors that influence supermarket sourcing and procurement decisions in case-study countries, the study contributed to literature by identifying the type of small-scale farmers who access chain supermarkets in case-study countries, the study contributed by identifying the factors that influence farmers decisions to supply FFV markets and the study showed that supermarkets involvement in the FFV and dairy supply chains in case-study countries had a positive impact in these sectors.Thesis (PhD)--University of Pretoria, 2009.Agricultural Economics, Extension and Rural Developmentunrestricte

Growth, development and yield of safflower genotypes in response to environmental variations

Safflower (Carthamus tinctorius L.) is a crop that is drought tolerant and grown in arid and semi-arid lands (ASALs) for its commercial utility as vegetable oil, animal feed, cut flower, leafy vegetable, pharmaceuticals, foods colorant, textile dye, cosmetics, and biofuel production. These important attributes make safflower an ideal crop to diversify the economy and improve the socioeconomic status of many smallholder farmers in ASALs. This study evaluated the growth, development, and yield of five safflower genotypes in three different locations in the southern part of Botswana under farmers’ fields during winter and summer. The results showed that there was a significant (P ≤ 0.05) genotypic variability for all phenological development (days to emergence, stem elongation, and flowering), plant growth (plant height and shoot biomass), the yield and yield components (number of branches/plant, number of capitula/plant and 1000-seed weight), oil content and oil yield. However, genotypes did not vary significantly (P ≥ 0.05) in number of primary branches/plant. The results showed that winter planting significantly (P ≤ 0.05) promoted safflower growth and yield than planting in summer. The growth, development, yield, and yield components of safflower genotypes varied across locations with Ramonaka being the most favorable. The GGE biplot revealed that genotype Kenya-9819 was found to be the most stable and adaptable with above-average yields. Sebele winter planting was the best representative environment and most suitable for discriminating genotype performance. The genotype by yield*trait combination (GYT) biplot revealed that genotypes ranked as Kenya9819 > Turkey > Sina > PI537636 > Gila. The results suggested that safflower was best planted in winter and that Kenya9819 was the best genotype to be planted in the greater Gaborone region

Surface sterilant effect on the regeneration efficiency from cotyledon explants of groundnut (Arachis hypogea L.) varieties adapted to eastern and Southern Africa

Five groundnut (Arachis hypogea L.) varieties - ICGV-12991, ICGV-99568, ICGV-90704, CG-2 and Chalimbana - that are adapted to Eastern and Southern Africa were compared to variety JL 24 for their regeneration response in tissue culture. Sodium hypochlorite and mercuric chloride were compared for efficiency as sterilizing agents and subsequent effect on regeneration. All five varieties formed shoot buds that elongated well on shoot elongation medium. ICGV-90704 and Chalimbana performed betterthan the other three varieties for shoot organogenesis although all varieties produced healthy rooted plants in vitro that were successfully transferred to the greenhouse where they exhibited normal growth, flowering and seed set. Both sterilizing agents were suitable, but mercuric chloride was lessharmful than sodium hypochlorite. This study established a basis for genetic engineering activities on African groundnuts in the future

Evaluation of the shoot regeneration response in tissue culture of pigeonpea (Cajanus cajan [L.] Millsp.) varieties adapted to eastern and southern Africa

Seven varieties of pigeonpea (Cajanus cajan [L.] Millsp.) of varying growth durations and adapted to a wide range of environments across eastern and southern Africa were evaluated for their shoot regeneration response in tissue culture. On a standardized shoot regeneration medium, the shortduration varieties (ICPV 88091 and ICPV 86012) generally responded faster and better than the medium duration (ICEAP 00554 and ICEAP 00557) and long duration (ICEAP 00020, ICEAP 00040 and ICEAP00053) varieties. However, all the tested varieties produced healthy rooted plants in vitro that could be transferred to the greenhouse where they exhibited normal growth, flowering and viable seed set. Thisstudy established the basis for genetic engineering of African pigeonpea varieties

SAFFLOWER GENOTYPE BY PLANT DENSITY ON YIELD AND PHENOLOGICAL CHARACTERISTICS

Safflower ( Carthamus tinctorius L.) is a temperate plant grown in arid and semi-arid regions of the world, and is the most drought tolerant oilseed crop. The objective of this study was to evaluate the effect of genotype and plant density on growth, phenology and yield of safflower. Treatments included five safflower genotypes and six plant densities laid out in a randomised block design. Increasing plant density from 62,500 to 100,000 plants ha-1 significantly (P < 0.05) increased leaf area index (LAI), leaf area duration (LAD), total leaf chlorophyll content (Tchl) and net assimilation rate (NAR) at all phenological stages in both winter and summer. For all genotypes, the highest LAI, LAD, Tchl, NAR, total dry matter accumulation (TDM) and seed yield resulted at a plant density of 100,000 plants ha-1. Maximum LAI, LAD, NAR and Tchl were observed at 50% flowering, compared to other phenological stages in all genotypes and plant densities. In general, genotype \u2018Sina\u2019 at 100,000 plants ha-1 significantly (P < 0.05) had the highest LAI, LAD, Tchl, TDM and seed yield compared to other genotypes and plant densities in both summer and winter.Le carthame ( Carthamus tinctorius L.) est une plante temp\ue9r\ue9e cultiv\ue9e dans les r\ue9gions arides et semi-arides du monde. Il est la plante ol\ue9agineuse la plus tol\ue9rante \ue0 la s\ue9cheresse. L\u2019objectif de cette \ue9tude \ue9tait d\u2019\ue9valuer l\u2019effet du g\ue9notype et de la densit\ue9 v\ue9g\ue9tale sur la croissance, la ph\ue9nologie et le rendement du carthame. Les traitements comprenaient cinq g\ue9notypes de carthame et six densit\ue9s de plantes dispos\ue9es dans une conception en blocs randomis\ue9s. L\u2019augmentation de la densit\ue9 v\ue9g\ue9tale de 62500 \ue0 100000 plantes ha-1 de mani\ue8re significative (P <0,05) a augment\ue9 l\u2019indice de surface foliaire (LAI), la dur\ue9e de la surface foliaire (DAL), la teneur totale en chlorophylle des feuilles (Tchl) et le taux net d\u2019assimilation (NAR) \ue0 toutes les \ue9tapes ph\ue9nologiques en hiver et en \ue9t\ue9. Pour tous les g\ue9notypes, les plus hauts LAI, LAD, Tchl, NAR, l\u2019accumulation totale de mati\ue8re s\ue8che (TDM) et le rendement en graines ont abouti \ue0 une densit\ue9 v\ue9g\ue9tale de 100 000 plantes ha-1. Un maximum de LAI, LAD, NAR et Tchl a \ue9t\ue9 observ\ue9 \ue0 50% de floraison, par rapport \ue0 d\u2019autres \ue9tapes ph\ue9nologiques dans tous les g\ue9notypes et densit\ue9s v\ue9g\ue9tales. En g\ue9n\ue9ral, le g\ue9notype \uabSina\ubb \ue0 100 000 plantes ha-1 (P <0,05) avait le rendement en LAI, LAD, Tchl, TDM et en graines le plus \ue9lev\ue9 par rapport aux autres g\ue9notypes et densit\ue9s v\ue9g\ue9tales en \ue9t\ue9 et en hiver

NUTRITIONAL VALUE OF SAFFLOWER WHOLE SEED AS ANIMAL FEED IN SEMI-ARID SOUTHERN AFRICAN CONDITIONS

Safflower ( Carthamus tinctorius L.) is a multipurpose crop, grown for its high quality edible oil (poly unsaturated and monounsaturated fatty acids), and as a horticultural crop (vegetable and cut flower). It is also grown for flavouring and colouring foods, as herbal tea, livestock feed, pharmaceuticals, dyes, paints and biodiesel.The objective of this study wasto evaluate the influence of safflower genotype on the nutritional quality of whole seed used as livestock feed. Nine safflower genotypes (eight exotic and one local) were grown in winter and summer. The seeds were harvested at physiological maturity and analysed for different nutritional variables. Whole safflower seeds dry matter (DM), crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL) and ash varied significantly, depending on genotype and growing season. The seed mineral content (P, K, Mg and Na) also varied across genotypes. Safflower whole seeds have great potential to serve as an excellent livestock feed in semi-arid conditions.Le carthame ( Carthamus tinctorius L.) est une culture polyvalente, cultiv\ue9e pour son huile comestible de haute qualit\ue9 (acides gras polyinsatur\ue9s et monoinsatur\ue9s) et comme culture horticole (l\ue9gume et fleur coup\ue9e). Il est \ue9galement cultiv\ue9 pour aromatiser et colorer les aliments, comme les tisanes, les aliments pour le b\ue9tail, les produits pharmaceutiques, les colorants, les peintures et le biodiesel. L\u2019objectif de cette \ue9tude \ue9tait d\u2019\ue9valuer l\u2019influence du g\ue9notype du carthame sur la qualit\ue9 nutritionnelle des semences enti\ue8res utilis\ue9es comme aliments pour le b\ue9tail. Neuf g\ue9notypes de carthame (huit exotiques et un local) ont \ue9t\ue9 cultiv\ue9s en hiver et en \ue9t\ue9. Les graines ont \ue9t\ue9 r\ue9colt\ue9es \ue0 maturit\ue9 physiologique et analys\ue9es pour diff\ue9rentes variables nutritionnelles. Les mati\ue8res s\ue8ches (DM) de carthame entier, les prot\ue9ines brutes (CP), les fibres d\ue9tergentes neutres (NDF), les fibres d\ue9tergentes acides (ADF), la lignine d\ue9tergente acide (ADL) et les cendres varient consid\ue9rablement selon le g\ue9notype et la saison de croissance. La teneur en min\ue9raux des graines (P, K, Mg et Na) variait \ue9galement d\u2019un g\ue9notype \ue0 l\u2019autre. Les graines de carthame enti\ue8res ont un grand potentiel pour servir d\u2019excellent aliment pour le b\ue9tail dans des conditions semi-arides

GENOTYPE AND PLANT DENSITY EFFECTS ON OIL CONTENT AND FATTY ACID COMPOSITION OF SAFFLOWER

Safflower ( Carthamus tinctorius L.) is a multipurpose oilseed crop that is tolerant to drought, saline, heat and cold conditions; and yields high quality edible seed oil. The objective of this study was to evaluate the effect of plant density and genotypes on oil content and fatty acid composition of safflower. A field experiment was conducted in the years 2015 and 2016, during winter and summer seasons. Treatments included five safflower genotypes and six plant densities. Genotype and plant density significantly interacted (P < 0.05) to influence oil content and fatty acid composition of safflower. Increasing plant density from 62,500 to 100,000 plants ha-1 significantly (P < 0.05) increased the oil concentration from 16 to 54%, depending on the interaction between genotype and plant density and genotype by environment (winter and summer seasons). However, as plant density increased from 100,000 to 200,000 plants ha-1, safflower oil content significantly (P < 0.05) decreased in all genotypes. The lowest and highest oil contents was produced by genotype \u2018Gila\u2019 planted at density 62,500 or 200,000; and \u2018Sina\u2019, \u2018Pi 537 636\u2019 at 100 000 or 125, 000 plants ha-1 in winter or summer, respectively. Fatty acid composition was significantly influenced by genotype and plant density interactions during the two growing seasons. The main fatty acids identified included linoleic, oleic, stearic and palmatic. There was a significant (P < 0.05) increase in linoleic acid content and a decrease in oleic, palmatic and stearic as plant density increased from 62,500 to 100,000 plants ha-1, depending on genotype or growing season. Genotype \u2018Sina\u2019 at 100,000 plants ha-1 produced the highest oil content and with high unsaturated fatty acid concentrations.Le carthame ( Carthamus tinctorius L.) est une plante de graines ol\ue9agineuses polyvalente qui est tol\ue9rante \ue0 la s\ue9cheresse, \ue0 la salinit\ue9, \ue0 la chaleur et au froid; et il donne de l\u2019huile de graines comestibles de haute qualit\ue9. L\u2019objectif de cette \ue9tude \ue9tait d\u2019\ue9valuer l\u2019effet de la densit\ue9 et des g\ue9notypes des plantes sur la teneur en huile et la composition en acides gras du carthame. Une exp\ue9rience sur le terrain a \ue9t\ue9 men\ue9e en 2015 et 2016, pendant les saisons d\u2019hiver et d\u2019\ue9t\ue9. Les traitements comprenaient cinq g\ue9notypes de carthame et six densit\ue9s de plantes. Le g\ue9notype et la densit\ue9 des plantes ont interagi de mani\ue8re significative (P <0,05) pour influencer la teneur en huile et la composition en acides gras du carthame. L\u2019augmentation de la densit\ue9 des plantes de 62 500 \ue0 100 000 plantes ha-1 de mani\ue8re significative (P <0,05) a augment\ue9 la concentration d\u2019huile de 16 \ue0 54%, selon l\u2019interaction entre le g\ue9notype et la densit\ue9 des plantes et le g\ue9notype par environnement (saisons d\u2019hiver et d\u2019\ue9t\ue9). Cependant, comme la densit\ue9 des plantes est pass\ue9e de 100 000 \ue0 200 000 plantes ha-1, la teneur en huile de carthame de mani\ue8re significative (P <0,05) a diminu\ue9 dans tous les g\ue9notypes. Les teneurs en huile les plus basses et les plus \ue9lev\ue9es ont \ue9t\ue9 produites par le g\ue9notype \uabGila\ubb plant\ue9 \ue0 une densit\ue9 de 62 500 ou 200 000; et \uabSina\ubb, \uabPi 537 636\ubb \ue0 100 000 ou 125 000 plantes ha-1 en hiver ou en \ue9t\ue9, respectivement. La composition en acides gras a \ue9t\ue9 significativement influenc\ue9e par les interactions entre le g\ue9notype et la densit\ue9 des plantes au cours des deux saisons de croissance. Les principaux acides gras identifi\ue9s \ue9taient les acides linol\ue9ique, ol\ue9ique, st\ue9arique et palmatique. Il y a eu une augmentation significative (P <0,05) de la teneur en acide linol\ue9ique et une diminution de l\u2019ol\ue9ique, palmatique et st\ue9arique lorsque la densit\ue9 des plantes est pass\ue9e de 62 500 \ue0 100 000 plantes ha-1, selon le g\ue9notype ou la saison de croissance. Le g\ue9notype \uabSina\ubb de 100 000 plantes ha-1 a produit la teneur en huile la plus \ue9lev\ue9e et avec des concentrations \ue9lev\ue9es en acides gras insatur\ue9s