Loading...
Dr
Van Jaarsveld, Corlien
Department: Botany
Research Interest: Plant ecophysiology, Plant propagation, Plant nutrition.
Active Community Engagement:
International Society for Horticultural Science.
South African Society of Crop Science.
Active Research Projects: Effect of agronomic variables on growth, yield and nutritional compositions of selected traditional leafy vegetables. Nitrogen use efficiency in pineapples
More Detail
Biography
Dr CM van Jaarsveld has been in the academic field for more than 20 years and lectured various modules in Botany, Soil Science, and Agronomy.
Research Intrest
Plant ecophysiology, Plant propagation, Plant nutrition.
5 results
Search Results
Now showing 1 - 5 of 5
- 2020| Society for Indonesi...Mncwango NC, Mavengahama S, Ntuli NR, van Jaarsveld CM. 2020. Diversity, consumption dynamics and ethnomedical claims of traditional leafy vegetables consumed by a rural community in the KwaMbonambi area, northern KwaZulu-Natal, South Africa. Biodiversitas 21: 1201-1207. Traditional leafy vegetables (TLVs) are mostly wild and informally-domesticated edible plant species. Their nutritious leaves, shoot tips, flowers and fruits are consumed as vegetables, particularly by rural communities in Africa. However, their consumption and cultivation are still marginal. This study aimed to identify the most preferred TLVs, as well as factors that affect the consumption and cultivation of these species. A questionnaire was administered among 100 respondents to record the preferred TLVs; the reason (s) for preference; consumption frequency; and constraints towards consumption of these vegetable species. This study recorded a total of 18 TLVs that belong to 14 genera and 11 families. Among these, Amaranthus hybridus, A. spinosus, A. thunbergii, Bidens biternata and Corchorus olitorius were the most preferred species. Vegetables were preferred primarily based on the taste; where most people ate them once a week when they are available. The major TLV consumption constraints were seasonal availability and low shelf life. A decline in the availability of TLVs was primarily caused by drought. Regardless of the observed decline, only 23% of respondents practiced informal cultivation of Amaranthus species. Bidens pilosa, Momordica balsamina, and Corchorus olitorius vegetable species were also known to possess some medicinal values. Future research on improving taste, increasing edible plant parts and elongating shelf life for preferred TLVs, is a necessity.
- 1
- 16
- 0
- Mineral sands mining is worldwide an environmental issue and also at the Hillendale mine in KwaZulu-Natal, South Africa. The post-mined soil is to be rehabilitated to sugarcane cropping. One of the concerns with the post-mined soil which is reconstituted with a 70:30 mixture of sand: slimes (silt-plus-clay fraction), is its low phosphorus (P) status, which could be limiting for optimum sugarcane production. A field experiment was conducted on a reconstituted soil at Hillendale to establish the availability of either residual or applied inorganic P to the plant and first ratoon sugarcane crop. Four treatments were evaluated including those where P fertilizer was omitted, applied at half the recommended rate or introduced equal to the recommended rate according to chemical analysis of the soil. In the fourth treatment, no fertilizer was applied at all, whereas nitrogen (N) and potassium (K) were added at recommended rates in the first three treatments. Phosphorus application had a significant effect on sugarcane fractional light interception and aboveground biomass yield of the plant and first ratoon crops, and stalk length and diameter of the first ratoon crop. Pol, brix, purity and fibre content and tiller number were not affected by P application. The application of P increased the foliar N, P, K, calcium (Ca), magnesium (Mg) and sulphur (S) contents of both crops. However, foliar N, P and K were deficient in the first ratoon crop even in the case where fertilizer was applied at the recommended rates, which could have been because of waterlogging. The possible effect of waterlogging on P uptake needs to be addressed in future studies in this reconstituted soil.
- 1
- 12
- 0
- Participatory selection of amaranthus genotypes in the KwaMbonambi Area, KwaZulu-Natal, South Africa2021| MDPIParticipatory variety selection (PVS) is a process that tests promising genotypes in farmers’ fields through a close farmer–researcher collaboration approach, which enhances the acceptance of new varieties by farmers. However, limited studies have been conducted to select Amaranthus genotypes that have potential for future breeding programmes in South Africa. Therefore, this study was aimed at selecting Amaranthus genotype(s) that is/are preferred by farmers in northern KwaZulu-Natal, using the PVS approach. Seedlings of fifteen Amaranthus genotypes were each planted in separate 10 × 10 m plots. Fourteen local farmers managed these genotypes and also determined the preferred traits to be used to evaluate them. These traits were: mild taste; profuse stem branching; big and numerous leaves; soft texture; and longer shelf life. Plants at four months after transplant were then evaluated and ranked according to farmers’ preferred traits using score sheets designed on a four-point Likert scale or five-point hedonic scale. However, genotype ACAT seed fair had the best scoring for appealing taste and aroma, and profuse branching. The TOT 8789 genotype had the largest and softest leaves. Again, A. thunbergii had the most numerous leaves of them all. These genotypes are thus recommended for multi-environment testing, seed multiplication, genetic improvement, and promotion for cultivation in South Africa.
- 1
- 22
- 0
- 2025| Frontiers MediaCucurbita argyrosperma Huber is a traditional leafy vegetable crop where different plant parts are consumed by rural communities in South Africa especially in the northern KwaZulu-Natal, South Africa. Goat manure is a nutrient-rich organic fertilizer that is readily available in rural communities of KwaZulu-Natal. Little is known about the organic fertilizer requirements of C. argyrosperma. Therefore, this study aimed to determine the effect of goat manure application on the growth and yield of C. argyrosperma. A field experiment was conducted at the University of Zululand farm in northern KwaZulu-Natal in which C. argyrosperma was grown under six goat manure application rates (0, 5, 10, 15, 20 and 25 t ha–1) over two seasons in a randomized complete block design with four replications. Data were collected on vegetative growth traits (vine length, stem diameter, leaf area, number of branches and leaves, and leaf chlorophyll content), as well as marketable yield (shoot, fruit and seed fresh mass, shoot dry mass, and fruit and seed number). An analysis of variance test was performed on the pooled data to identify significant differences at p < 0.05 and the means were separated using Tukey’s test. Plants treated with 20 and 25 t ha–1 manure had significantly (p < 0.05) more branches and leaves, longer and heavier harvested shoots and a higher fruit number and mass and 100-seed mass than control. The remaining parameters increased with an increase in goat manure application, but not significantly. The yields obtained in this study were relatively low compared to typical yields for this crop and require further investigation. This study showed goat manure application could improve growth and yield of C. argyrosperma and ultimately contribute to food security in rural communities at affordable agronomic inputs.
- 1
- 10
- 0
- 2019| Gaurav PublicationsPolyploidy was induced in Corchorus olitorius L., a traditional leafy vegetable, which is also consumed by the rural community at KwaMbonambi. Corchorus seeds were treated with colchicine at four different concentrations (0.025, 0.05, 0.075 and 0.1 g/l) for 2, 4, 6, 8 and 10 h, respectively. For the control, treatment seeds were imbibed in water only. After germination in petri dishes, seedlings were transplanted to seedling trays and then to plastic pots and kept under shade cloth at the University of Zululand. There were three replicates for each treatment in a completely randomized design. Several morphological traits were measured and data were subjected to ANOVA, principal component analysis and cluster analysis. Significant (P<0.05) variation was observed among all traits measured, with all traits decreasing in value as the colchicine concentration and treatment duration increased, with the exception of stem girth. Of all traits measured, only the leaf chlorophyll content of plants treated with 0.025 g/l colchicine for two hours was significantly (P<0.05) higher than for the control treatment. The principal component analysis showed that the first two principal components (PC1 and PC2) contributed more than 80% of the total variation. The Pearson's correlation coefficients were positive and significant (P<0.05) for the majority of studied traits. Clustering pattern showed a close relationship between the C. olitorius plants treated with low colchicine concentrations and shorter treatment durations. A similar trend was also observed in the biplot. Colchicine treatment induced sufficient variability among treatments to be useful in future breeding programmes.
- 1
- 1
- 0
