Tsoutsoura, Niki
(2025)
Winged bean – a new soybean for the tropics? Genomic analysis for improving nutritional value and breeding efficiency in Psophocarpus tetragonolobus seeds.
PhD thesis, University of Nottingham.
Abstract
Climate change, population growth, and lack of nutritional diversity in diets present significant challenges to food security and human health. The need for alternative protein sources is urgent, and the underutilised winged bean (Psophocarpus tetragonolobus (L.) DC.) grown in tropical regions emerges as a promising candidate due to its high nutritional profile. With high protein content ranging from 30-40% and oil content of 15-20%, winged bean could play a critical role in enhancing dietary diversity and addressing nutritional deficiencies. This thesis assessed the nutritional composition and in vitro digestibility of winged bean seeds; identified for the first time QTLs linked to nutritional traits such as protein and oil; and performed transcriptomic analysis on developing pods and seeds for the first time.
The winged bean seeds analysed were sourced from field trials in Malaysia, revealing significant variation in protein and fat content among different accessions, with protein levels between 35.4% and 42.6% and fat content ranging from 14.2% to 21.8%. Notably, genotype-environment interactions significantly influenced fat content (p=0.002), highlighting the complexity of factors affecting crop nutrition. The amino acid profile analysis indicated that methionine is the limiting amino acid, resulting in a digestible indispensable amino acid score (DIAAS) of 0.14 to 0.21, significantly lower than the DIAAS of casein, which stands at 0.77. This suggests that while winged bean seeds are a good source of protein, supplementation with other amino acid sources high in methionine may be necessary. For the use of winged bean seeds in animal feed, phytic acid content and total phenolics were measured. However, a more accurate assessment of the impact of the antinutritional factors on digestibility is needed.
The next step, after evaluating the nutritional composition of winged bean seeds was to identify the quantitative trait loci (QTL). This study is the first to perform QTL analysis on nutritional traits such as protein and oil content, aiming to identify genetic markers associated with key genes contributing to these traits. Sixteen QTLs and several genes were identified, three of which were characterised as significant and linked to fatty acid contents like linoleic and behenic acids. These findings offer valuable insights for breeding programs aiming to improve the nutritional quality of winged bean. More work needs to be done including research that combines genomics, transcriptomics, and metabolomics data for improved winged bean varieties.
Furthermore, this thesis includes the first transcriptomic analysis of winged bean developing seeds and pods, uncovering differentially expressed genes related to critical pathways, including fatty acid biosynthesis, seed storage proteins, and flavonoid biosynthesis. A total of 7,954 genes were differentially expressed in the pods, and 10,765 genes in the seeds during development. The reported findings provide a baseline for functional and comparative genomic analysis, helping to better understand the developmental process and mechanisms that contribute to and control the nutritional value of winged bean seeds and pods
Collectively, this research highlights the potential of winged bean as an underutilised crop to improve nutrition and diversify agriculture. Emphasis should be given to further genomic studies to optimise its nutritional benefits in response to the challenges posed by climate change and population growth. More research is needed in developing such underutilised crops for enhancing food and nutritional security.
| Item Type: |
Thesis (University of Nottingham only)
(PhD)
|
| Supervisors: |
Brameld, John
Mayes, Sean |
| Keywords: |
Winged bean, soybean, genomic analysis, Psophocarpus tetragonolobus, protein, oil content, seeds, QTL analysis, RNA sequencing, antinutritional factors, nutritional value, climate change, underutilised crop |
| Subjects: |
S Agriculture > SB Plant culture |
| Faculties/Schools: |
UK Campuses > Faculty of Science > School of Biosciences |
| Item ID: |
81202 |
| Depositing User: |
Tsoutsoura, Niki
|
| Date Deposited: |
31 Jul 2025 04:40 |
| Last Modified: |
31 Jul 2025 04:40 |
| URI: |
https://eprints.nottingham.ac.uk/id/eprint/81202 |
Actions (Archive Staff Only)
 |
Edit View |
Tools
Tools
