Comparative evaluation of the germination capability of three morphologically different wild genotypes of Corchorus olitorius L. from Northern KwaZulu-Natal, South Africa

Corchorus olitorius L. is a wild plant utilised as a vegetable in many parts of Africa. Wild indigenous vegetables have been recommended to alleviate nutritional deficiencies and household food insecurity. Efforts to domesticate and cultivate wild C. olitorius and other wild vegetables are being hampered by seed dormancy. The main cause of dormancy in C. olitorius has been suggested to be an impermeable seed coat. This study evaluates the response of wild genotypes of C. olitorius with different seed sizes to various dry heat and hot water treatments. Steeping seeds in boiling water (95°C) for 10 s and soaking seeds in a hot water bath at 80°C for 10 min resulted in a highest response to germination in the tested genotypes of this species. The study also recorded significant interactions between heat treatment and seed sizes. It was therefore concluded that genotypes of C. olitorius with different sizes require diverse durations of exposure to heat treatment methods to break dormancy caused by an impermeable seed coat.Key words: Corchorus olitorius, genotypes, germination, heat treatment, wild vegetables species

Influence of fertilizer application on biomass yield and nutritional quality of Mustard Spinach (Florida) Broadleaf in South Africa

Mustard Spinach (Florida Broadleaf) is an indigenized leafy vegetable grown in Southern Africa. It is a good source of vitamins and mineral nutrients. An understanding of its response to fertilizer application is important in developing cultural practices for improved yield of the crop. Furthermore, improving fertilizer use efficiency such as nitrogen (N), phosphorus (P) and potassium (K) would result in improving cropping system. Therefore, a field experiment was conducted in 2010 and 2011 winter cropping season to determine the influence of NPK applications and their interactions on biomass yield and nutritional values of Mustard spinach. A randomized complete block design replicated four times were used for the experiment. ANOVA showed significant variation among the treatments. The values for total fresh biomass yield ranged from 252–4,510 and 820–4,982 kg ha-1 in 2010 and 2011 cropping seasons, respectively. Omission of P had 4,510 kg ha-1 of total fresh biomass yield, while omission of K had 4,506 kg ha-1 in the first season. The lowest N content (2.63%) was recorded when nitrogen fertilizer was omitted. Full NPK application increased the content of N and K on the leaf tissues of Mustard Spinach. The highest percentage of dietary fiber was observed when K was omitted. The values recorded for ascorbic acid content varied from 126.94 and 117.42 mg 100g-1 , respectively for both seasons. Iron was more concentrated on the treatments, where K was omitted. Mustard Spinach responded to fertilizer application and the results validated that application of NPK had a beneficial effect on increased production and productivity of the crop tested for small scale farmers

Voices of the hungry: a qualitative measure of household food access and food insecurity in South Africa

South Africa is rated a food secure nation, but large numbers of households within the country have inadequate access to nutrient-rich diverse foods. The study sought to investigate households’ physical and economic access and availability of food, in relation to local context which influences households’ access to and ability to grow food which may affect the dietary quality. We sought to understand self-reported healthy diets, food insecurity from the perspective of people who experienced it, barriers to household food security and perceptions and feelings on food access as well as strategies households use to cope with food shortages and their perceptions on improving household food security

Utilization of wild vegetables in four districts of northern KwaZulu-Natal Province, South Africa

A study was conducted in northern KwaZulu-Natal Province, South Africa to gather information on the availability and extent of utilization of wild vegetables within some communities. The study revealed that wild vegetables were important in the diets of most rural people in northern KwaZulu - Natal. They were consumed as relish, although they were not being cultivated. The method of acquiring these vegetables was by gathering them from homesteads and the wild. These vegetables were also believed to be medicinal. The local names of wild vegetables varied among villages in the same district such that one vegetable in one village was given to a different species of vegetable in another village. They were reportedly abundant during summer and there was a decrease in availability off-season leaving vulnerable families who rely on them with a food shortage. © 2011 Academic Journals.Articl

Assessment of selected soil nutrients and irrigation water quality in the dryland area of Chivi district, Zimbabwe

The levels of selected nutrients in soils and chemical composition of irrigation water were investigated in 16 villages from the dryland areas of Chivi District in Zimbabwe. The objective was to generate a biophysical knowledge base on the soil fertility status across different villages, and to relate it to site history, management and quality of surface and groundwater used for irrigation. Soil samples were collected from the fields, gardens, cultivated vleis, and virgin land while irrigation water samples were collected from rivers, vlei and shallow wells used to irrigate horticultural crops. Results revealed medium to deficient levels of nitrogen (N) and phosphorus (P) (>75% of the sampled units), and to a lesser degree, potential soil acidity problems on selected fields. The considerably higher soil pH and exchangeable bases in the irrigated gardens and vleis than in the fields and virgin land reflected the impact of management and land utilization. The chemical quality of the sampled water used for irrigation of horticultural crops all showed high chloride hazard. There was need to ascertain the magnitude of crop productivity against applied soil fertility inputs to establish the level and rate of nutrients mining from the soils. © 2011 Academic Journal.Articl

The role of wild vegetable species in household food security in maize based subsistence cropping systems

Publication of this article was funded by the Stellenbosch University Open Access Fund.The original publication is available at http://www.springer.com/life+sciences/agriculture/journal/12571Wild vegetables (WV) are an important source of food in the maize based subsistence farming sector of rural South Africa. Their main role is as relish as they are used as an accompaniment for staple cereal based diets. They are generally reported to be rich in micronutrients. Although they may be consumed in small quantities, they influence the intake of cereal staples, manage hunger and play a central role in household food security for the poorer rural groups. Mixing several WV species in one meal contributes to dietary diversity in terms of more vegetable types as well as in terms of choice of relish. For some very poor families WV are substitutes for some food crops. The seasonal occurrence of these vegetables leaves many families without a food source during the off-season. Wild vegetables increase agro-biodiversity at the household level. This agrobiodiversity helps in buffering against the accumulation and multiplication of pests and diseases and provides important cover for the soil. Further research on agronomic, social and economic dimensions is required to understand the roles of WV in subsistence farming systems in South Africa.Stellenbosch UniversityPublishers' Versio

Exploring the implications of critical complexity for the study of social-ecological systems

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