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Groundnut is an important global food and oil crop that underpins agriculture-dependent livelihood strategies meeting food, nutrition, and income security. Aflatoxins, pose a major challenge to increased competitiveness of groundnut limiting access to lucrative markets and affecting populations that consume it. Other drivers of low competitiveness include allergens and limited shelf life occasioned by low oleic acid profile in the oil. Thus grain off-takers such as consumers, domestic, and export markets as well as processors need solutions to increase profitability of the grain. There are some technological solutions to these challenges and this review paper highlights advances in crop improvement to enhance groundnut grain quality and nutrient profile for food, nutrition, and economic benefits. Significant advances have been made in setting the stage for marker-assisted allele pyramiding for different aflatoxin resistance mechanisms—in vitro seed colonization, pre-harvest aflatoxin contamination, and aflatoxin production—which, together with pre- and post-harvest management practices, will go a long way in mitigating the aflatoxin menace. A breakthrough in aflatoxin control is in sight with overexpression of antifungal plant defensins, and through host-induced gene silencing in the aflatoxin biosynthetic pathway. Similarly, genomic and biochemical approaches to allergen control are in good progress, with the identification of homologs of the allergen encoding genes and development of monoclonal antibody based ELISA protocol to screen for and quantify major allergens. Double mutation of the allotetraploid homeologous genes, FAD2A and FAD2B, has shown potential for achieving >75% oleic acid as demonstrated among introgression lines. Significant advances have been made in seed systems research to bridge the gap between trait discovery, deployment, and delivery through innovative partnerships and action learning.

Diploid and tetraploid wild relatives of cultivated peanut are genetically diverse, providing rich sources of genetic resources for tapping resistance to various biotic and abiotic stresses. Arachis glabrata Benth. is a tetraploid (2n = 40) rhizomatous species that is reported to be tolerant to water deficit stress. Identification of A. glabrata accessions with high SPAD chlorophyll meter reading (SCMR) and low specific leaf area (SLA) values would be an option for improving water deficit stress tolerance in peanut. An investigation was undertaken to study the genetic diversity of A. glabrata accessions using molecular markers as well as surrogate traits (SLA and SCMR) for water deficit stress to identify stable sources for SCMR and to identify DNA markers linked to SCMR. SCMR showed high heritability and genetic advance as percent of mean (GAM) and a negative relation with SLA in A. glabrata. High heritability and high GAM indicates additive gene action. A high level of genetic diversity was observed in A. glabrata accessions, indicating that these populations had not experienced major genetic bottlenecks or genetic drift. Eight random amplified polymorphic DNA markers were identified with significant association to SCMR. [ABSTRACT FROM AUTHOR]