A sustainable supply of plant protein is critical for future generations and needs to be achieved while reducing green house gas emissions from agriculture and increasing agricultural resilience in the face of climate volatility. Agricultural diversification with more nutrient-rich and stress tolerant crops could provide the solution. However, this is often hampered by the limited availability of genomic resources and the lack of understanding of the genetic structure of breeding germplasm and the inheritance of important traits. One such crop with potential is winged bean ( Psophocarpus tetragonolobus ), a high seed protein tropical legume which has been termed ‘the soybean for the tropics’. Here, we present a chromosome level winged bean genome assembly, an investigation of the genetic diversity of 130 worldwide accessions, together with two linked genetic maps and a trait QTL analysis (and expression studies) for regions of the genome with desirable ideotype traits for breeding, namely architecture, protein content and phytonutrients.

Human dietary patterns are a major cause of environmental transformation, with agriculture occupying ~ 50% of global land space, while food production itself is responsible for ~ 30% of all greenhouse gas emissions and 70% of freshwater use. Furthermore, the global population is also growing, such that by 2050, it is estimated to exceed ~ 9 billion. While most of this expansion in population is expected to occur in developing countries, in high-income countries there are also predicted changes in demographics, with major increases in the number of older people. There is a growing consensus that older people have a greater requirement for protein. With a larger and older population, global needs for protein are set to increase. This paper summarises the conclusions from a Rank Prize funded colloquium evaluating novel strategies to meet this increasing global protein need.

Climate change, population growth and increasingly homogenised diets are a threat to food security and human nutritional status. There is an urgent need to incorporate highly nutritious crops into the human diet to provide new sources of nutrition, to diversify agriculture and to meet the challenges of climate change. Winged bean (Psophocarpus tetragonolobus (L.) DC.) is an underutilised crop with a relatively high protein content, grown in the humid tropic regions. Despite its many strengths, the crop suffers from a number of production, yield and utilisation-related constraints. In this chapter, we discuss the nutritional value of winged bean and how it can be improved by utilising genomic and transcriptomic data. We discuss the importance of identifying genes and gene functions, generating genetic linkage maps and developing molecular markers that could be used to accelerate plant breeding. Considerable genomics resources have been developed in major legumes such as soybean (Glycine max) and common bean (Phaseolus vulgaris) through transcriptome and genome sequencing. These provide opportunities for comparative genomic studies and translational research to improve minor crops such as winged bean. Winged bean genome sequencing is underway and will be published shortly. This will contribute to breeding improvement efforts. More research is needed to combine genomics, transcriptomics and metabolomics data to further improve winged bean for food and nutritional security.

Sulfur is an essential macronutrient for growth of higher plants. The entry of the sulfate anion into the plant, its importation into the plastids for assimilation, its long-distance transport through the vasculature, and its storage in the vacuoles require specific sulfate transporter proteins. In this study, mycorrhizal and non-mycorrhizal maize plants were grown for 60 days in an S-deprived substrate, whilst iron was provided to the plants in the sparingly soluble form of FePO4. On day 60, sulfate was provided to the plants. The gene expression patterns of a number of sulfate transporters as well as sulfate assimilation enzymes were studied in leaves and roots of maize plants, both before as well as after sulfate supply. Prolonged sulfur deprivation resulted in a more or less uniform response of the genes' expressions in the roots of non-mycorrhizal and mycorrhizal plants. This was not the case neither in the roots and leaves after the supply of sulfur, nor in the leaves of the plants during the S-deprived period of time. It is concluded that mycorrhizal symbiosis modified plant demands for reduced sulfur, regulating accordingly the uptake, distribution, and assimilation of the sulfate anion.