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

Variation in protein content, starch components, selected minerals and their bioavailability in bambara groundnut accessions

Introduction Bambara groundnut is a highly nutrient dense underutilized orphan crop, and has the potential to address malnutrition and food security. The study objectives were to estimate the variation in the concentration of protein, starch, amylose, iron (Fe), zinc (Zn), phytic acid (PA) and mineral bioavailability, to identify superior bambara accessions and to determine the interrelationship between measured traits. Materials and methods: Grain samples were collected from 59 accessions that were planted in two different locations over two seasons and used to measure the nutritional quality traits. Results: Significant variability among accessions in diverse locations and seasons for protein, Fe, Zn, and PA/Fe and PA/Zn ratios was observed. The average values of measured characteristics were protein (22.59 %), starch (36.52 %), amylose (21.15 %), Fe (38.83 mg kg−1), Zn (27.10 mg kg−1), PA (6239.24 mg kg−1), PA/Fe (17.74) and PA/Zn (22.87) content. Significant positive correlations between protein, Fe and Zn were observed and these traits were negatively correlated with starch, amylose, PA, PA/Fe and PA/Zn ratio. Accessions SB 4–4 A and M 3 were superior for more than one nutritional trait and had good mineral bioavailability. Conclusion Superior accessions can be used as potential parents for the development of nutritionally improved bambara cultivars

Comparative growth and yield of taro (Colocasia esculenta) accessions cultivated in the Western Cape, South Africa

The growth and yield characteristics of six accessions (Amadumbe 2914, Amadumbe 3053, Amadumbe 43, Amadumbe 56, Amadumbe Amzam 3553/5118 and Amadumbe 2919) of Colocasia esculenta (taro) were compared in the Western Cape Province of South Africa. A randomized complete block design with five replications was used. Differences in growth and yield observed among the accessions may be attributed to non-uniformity in the size of the propagules used for establishment of the trial, genotypic and/or climatic factors. Amadumbe 2914, Amadumbe 3053, Amadumbe 43 and Amadumbe 56, established with bigger cormels (20.37 - 28.33 g) consistently showed superiority in terms of plant height, leaf area and yield over Amadumbe Amzam 3553/5118 and Amadumbe 2919, established with smaller cormels (15.00 and 16.67 g). However, there was no appreciable difference in the size and weight of individual cormels produced by all six accessions. Due to small cormel sizes, a higher proportion (about 92%) of the cormel yield could be classified as unmarketable. Good nutrition can be provided by the leaves and tubers, even though maximum yield may not be attained in the Western Cape due to temperature, radiation and day length limitations, especially in winter. Continued research to determine whether yield can be improved with better nutrition and agronomic practices, is warranted

African fermented root and tuber-based products

In this chapter, our interest is on the biochemistry, nutritional and functional profiles, as well as the microbiota of African fermented root and tuber-based products

Evaluation and selection of taro [Colocasia esculentra (L.) Schott] accessions under dryland conditions in South Africa

Published online: 08 Oct 2018Taro [Colocasia esculenta (L.) Schott] is an important underutilised staple food crop in South Africa, with a lot of potential to address food insecurity among poor rural households. Development of high yielding stable taro cultivars is one of the most important goals of plant breeders. Twenty-nine taro accessions collected from major taro producing regions of the country were evaluated for growth performance, yield potential and stability under dryland conditions at two sites (Umbumbulu and Roodeplaat) in 2013, 2014 and 2015 cropping seasons. The experiment was laid in a randomised complete block design replicated three times. Growth and yield traits were measured. Analysis of variance and correlation analysis was done on all measured traits. The genotype by environment interaction was analysed using additive main effects and multiplicative interaction (AMMI). As a result, significant variation was observed for most of the traits except number of leaves and leaf width as well as number of suckers, while all the traits showed significant variation for location by year interaction. Number of corms showed significant variation for location by year by genotype interaction among all the traits evaluated. Genotype effect was highly significant (p < .01) on plant height, corm length, number of corms and significant (p < .05) on yield. The significant difference between genotypes for these traits proves that there was a genetic variability and there is a scope for selection. The correlation study also reveals that majority of the characters were positively correlated with each other. Total yield was positively and highly significantly (p < .01) correlated with all the measured traits. AMMI was effective in identifying stable genotypes. The top ranking cultivars per environment may be considered for cultivation under the specific environment, the stable cultivars may be considered for cultivation across all the taro growing regions