Agronomic Performance, Nutritional Phenotyping and Trait Associations of Okra (Abelmoschus esculentus) Genotypes in South Africa

Okra, Abelmoschus esculentus L. (Moench), is an important fruit vegetable crop which belongs to the family Malvaceae. It is a good source of protein, carbohydrates, vitamins, minerals, and enzymes that are often consumed in small quantities in developing country. Okra is a highly nutritious underutilized fruit vegetable crop in South Africa. However, despite its importance for food, nutritional, and health benefits, the crop is rarely produced in some areas of South Africa. The study was carried out to assess the genetic diversity using agro-morphological traits and nutritional contents towards future use in the okra breeding programme. The experiment was carried out at the Roodeplaat research farm of the Agricultural Research Council in a randomized complete block design replicated three times. Agro-morphological traits and selected nutrients were determined. The analysis of variance for both showed highly significant differences for most traits recorded. The multivariate analysis showed a wide genetic diversity among the okra genotypes, which could be exploited in selecting suitable and potential parents when breeding for high yield and nutritional qualities. The present study revealed the genetic potential of the genotypes studied and their importance for use in the breeding programme aimed toward addressing malnutrition, food security, and poverty alleviation by breeding for increased yields, and nutritional contents in South Africa

Draft genome sequence of Alternaria alternata isolated from onion leaves in South Africa

Alternaria alternata (Fr.) Keissler strain PPRI 21032 was isolated from onion leaves collected in Roodeplaat, Pretoria, South Africa. The whole genome of this strain was sequenced and produced a total of 33.12 Mb with a GC content of 50.9%. The whole genome comprises 11,701 predicted coding sequences.The Agricultural Research Council (ARC) of South Africa and the World Vegetable Center core donors [Republic of China (Taiwan), UK Department for International Development (DFID), United States Agency for International Development (USAID), Australian Centre for International Agricultural Research (ACIAR), Germany, Thailand, Philippines, Korea, and Japan].http://genomea.asm.orgam2017Forestry and Agricultural Biotechnology Institute (FABI)Microbiology and Plant Patholog

Characterisation of agro-morphological traits of corchorus accessions

http://www.tandfonline.com/loi/sagb202019-09-03hj2018Plant Production and Soil Scienc

Enhancement of the functional, pasting and textural properties of poundo yam flour through cassava flour supplementation

In this study, poundo yam flour was supplemented with cassava flour (5, 15, 30 and 50%) and the functionality of the flour and quality of the cooked dough were determined. The composite flours and yam flour (approx. 56%) were more dispersible than the cassava flour (approx. 50%). Cassava flour addition significantly (p ≤ 0.05) increased the lightness of poundo yam flour (75.65–84.67) and the ability of the flours to absorb water, but the lightness values (61.60–64.79) of the cooked dough did not change significantly (p > 0.05). Samples with cassava flour were firmer (7.56–22.87 N), stickier (2.51–5.92 Ns) and gummier (2.57–5.48 N) than the control dough. Sensory ratings were similar across the cooked poundo yam samples. This study demonstrated that cassava flour can be used to supplement yam flour for poundo yam flour production

Strengthening farmer-managed seed systems in South Africa

This report presents field activities carried out in the period 2019-2022 in support of farmer-managed seed systems in South Africa, in particular the conservation efforts and participatory variety selection (PVS) carried out by the community seed banks of Gumbu, Jericho and Sterkspruit. The PVS was done on four priority crops selected by the farmers, cowpea, okra, pearl millet and sorghum, with the support of DALRRD and the Agricultural Research Council - Vegetable, Industrial and Medicinal Plants (ARC-VIMP; formerly ARC-VOPI) campus at Roodeplaat (Gauteng), and the ARC-Grain Crops (ARC-GC) campus at Potchefstroom (North West Province). The report also presents a synthesis of results achieved since the start of the activities and identifies challenges encountered

Genetic variability among sorghum accessions for seed starch and stalk total sugar content

Sorghum (Sorghum bicolor (L.) Moench) is a staple food grain in many semi-arid and tropical areas of the world, notably in sub-Saharan Africa because of its adaptation to harsh environments. Among important biochemical components for sorghum for processors are the levels of starch (amylose and amylopectin) and total sugar contents. The aim of this study was to determine the genetic variation for total starch in the seed, its components and total sugar in the stalks of the sorghum accessions from Ethiopia and South Africa. Samples of 22 sorghum accessions were evaluated. Significant variations were observed in total starch (31.01 to 64.88 %), amylose (14.05 to 18.91 %), the amylose/amylopectin ratio (0.31 to 0.73) and total stalk sugar content (9.36 to 16.84 %). Multivariate analysis showed a wide genetic variation within and among germplasm accessions which could be used in the selection of parental lines for the improvement of traits of interest through breeding. The variation found among the sorghum accessions shows that an improved total starch and starch components and stalk sugar contents can be achieved through crossing these selected genotypes

Preliminary study on variability and heritability estimates of micronutrient composition in the immature fruits of okra (Abelmoschus esculentus) genotypes in South Africa

Okra is one of the important fruit vegetable crop but is an under-utilized and neglected plant species in South Africa. The immature fruits of okra is a good source of protein, minerals and vitamins. Despite its contribution to food, nutritional and health security, this crop is rarely cultivated and researched in South Africa. The study was carried out to assess the genetic variability and heritability estimates using micronutrient content such as iron, zinc and manganese in the immature green fruits of okra plant for future use in the okra breeding programme to increase nutritional value. The experiment was conducted at the Roodeplaat research farm of the Agricultural Research Council in a randomized complete block design replicated three times. The analysis of variance showed highly significant differences for all of three micronutrients recorded. This indicated that there were high level of genetic differences among the genotypes studied. Phenotypic and genetic coefficient of variations, broad-sense heritability (repeatability) and genetic advance were also estimated for iron, zinc and manganese, which could be exploited in selecting suitable and potential okra parents when breeding for high micronutrient contents. The phenotypic coefficient of variation ranged from 23.04% in Zn to 75.48% in Fe. Furthermore, the highest values for the genetic coefficient of variation was found in Fe. High heritability estimates were observed in all mineral elements Fe (99.86%), Mn (99.72%) and Zn (96.32%) evaluated indicating potential genetic gain as percentage of mean for Fe (155.38), Mn (69.20) and Zn (45.79), respectively when breeding for these micronutrient traits. The present study revealed the genetic potential of the genotypes studied and their importance for use in the quality-breeding programme aimed towards addressing malnutrition in South Africa

Effect of simulated gastrointestinal digestion on the phenolic compound content and in vitro antioxidant capacity of processed Cowpea (V. unguiculata) cultivars

The aim of this study was to analyze the phenolic content and antioxidant activity of five cowpea cultivars after processing and in vitro digestion. Raw cowpea samples showed a significant decrease in total phenolic content (TPC) when compared with the processed samples, however an increase was subsequently observed in digested samples. The antioxidant activity determined using, DPPH, ABTS, ferric reducing antioxidant power (FRAP) assay, and total peroxyl radical-trapping antioxidant parameter showed a similar trend to the phenolic content with a significant decrease in activity upon processing and an increase after digestion. In conclusion, all cowpea cultivars showed a high TPC content as well as an increased antioxidant activity after digestion indicating the potential health benefits which cowpea could provide to consumers. Therefore, this study shows that in vitro digestion improves the digestion and absorption of beneficial components of processed cowpea at the intestinal level.El objetivo de este estudio fue analizar el contenido fenólico y la actividad antioxidante de cinco cultivos de judía de careta después del procesado y la digestión in vitro. Las muestras crudas de judías de careta mostraron un descenso significativo en el contenido total de fenoles (TPC) cuando se comparó con las muestras procesadas, sin embargo se observó posteriormente un aumento en las muestras digeridas. La actividad antioxidante determinada utilizando DPPH, ABTS, el ensayo FRAP y el parámetro antioxidante total capturador de radicales peroxilo mostró una tendencia similar al contenido fenólico con una disminución significativa en la actividad frente al procesado y un aumento después de la digestión. En conclusión, todos los cultivos de judías de careta mostraron un alto contenido en TPC, como también un aumento en la actividad antioxidante después de la digestión indicando los beneficios potenciales para la salud que las judías de careta podrían aportar a los consumidores. Por lo tanto, este estudio muestra que la digestión in vitro mejora la digestión y la absorción de los componentes beneficiosos de las judías de careta procesadas a nivel intestinal

Efforts in breeding cowpea for aphid resistance: a review

Cowpea is an important food and nutritional security grain legume crop in the semi-arid regions of sub-Saharan Africa. Its production is limited by biotic factors including pre-harvest insect pests such as aphids. Aphids cause yield reductions, promotes the growth of sooty moulds, honeydew and as a result reduce photosynthetic processes and rates. Various methods have been deployed to try to control the damage of aphids in cowpea plants. The methods include the use of chemical insecticides, cultural, mechanical, biological controls and integrated pest management. However, these methods have not been very effective as smallholder farmers growing cowpea in marginal areas cannot afford them. Hence, host plant resistance/genetic control is the best and effective method for controlling aphids in cowpea plantations. Breeding for aphid resistance is one of the effective methods that can sustain the production and productivity of the cowpea for longer periods. Furthermore, assessing the presence of genetic diversity can also help in sourcing genes of novelty for addressing this important issue to increase the production and productivity of the crop. Recently, scientists have used various strategies to try to solve the challenge of aphid damage on cowpea. The objective of this review was to document the research progresses on aphid resistance breeding of cowpea to facilitate the breeding and conservation of cowpea germplasm. The review serves as a baseline information to guide future cowpea breeding for resistance to aphids