Smallholder farmers in sub-Saharan Africa grow maize under highly variable agro-ecological and socio-economic conditions, calling for breeding programmes that better address farmers’ conditions and needs. This study characterized farmers’ crop management practices and investigated genotype × environment (G × E) interaction patterns for maize yield in Eastern Zambia to guide the breeding strategy in this region. A participatory large-scale variety testing approach, comprising 980 mother and baby trials (MBTs) conducted under farmers’ own management practices, was implemented over the 2022 and 2023 seasons. Characterization of the MBT contexts revealed that adaptation to low nitrogen and delayed fertilization should be considered in the breeding strategy. In addition, delayed weedings explained a large proportion of genotype × farmer (G × F) interactions in both MT seasons, indicating that adaptation to weed pressure should deserve greater attention in breeding. These adaptation traits are particularly important for women, who provide most weeding labour and often have limited access to soil fertility resources. Non-repeatable G × F interactions across years, together with genotypic variance exceeding G × E interaction variance estimates, indicated that multi-year testing across MTs can identify superior and stable genotypes. At the same time, indications of specific adaptation to certain management conditions suggest potential for context-specific variety recommendations. This could offer a competitive advantage in Zambia’s maize seed market, where variety choice and information remain limited. Overall, decentralized farmer-managed testing underlined the importance of yield stability and generated reliable information on variety adaptation, while strengthening farmers’ capacity to make informed variety choices.
Tag: crop improvement
Agricultural intensification in the Sahel: Suggestions for stakeholders
Key messages
- More trees and shrubs on farmland increase soil organic matter and crop production. However, crop yields can be further increased with small amounts of spot-applied mineral fertilizer (microdosing).
- Farmer managed natural regeneration provides a firm foundation for further intensification. It is clear from research that nutrient use efficiency and rainfall-use efficiency depend on adding organic matter to soils, and particularly to sandy soils. However, over most of the Sahel, it is challenging to produce enough manure and biomass – at least until the arrival of newly regenerating trees and shrubs.
- Projects z to improve soil fertility should do so in tandem with promoting farmer managed natural regeneration, or do it in existing agroforestry parklands.
- As fertilizer prices increase, African smallholders find greater value in nitrogen-fixing trees.
Past trauma, better future: how stress memory shapes plant adaptation to drought
Can plants remember drought? Emerging evidence suggests that prior stress exposure leaves an epigenetic imprint, reprogramming plants for enhanced resilience. However, the stability and functional relevance of drought memory remain unresolved. This review synthesizes recent advances in epigenetic modifications, transcriptional reprogramming, and metabolic priming, critically assessing their roles in plant stress adaptation. DNA methylation dynamically reshapes chromatin landscapes, yet its transient nature questions its long-term inheritance. Histone modifications, particularly H3K9ac and H2Bub1, may encode stress signatures, enabling rapid transcriptional responses, whereas small RNAs fine-tune chromatin states to reinforce memory. Beyond epigenetics, physiological priming, including osmotic adjustments, antioxidant defenses, and hormonal crosstalk, introduces further complexity, yet its evolutionary advantage remains unclear. Root system plasticity may enhance drought resilience, but its metabolic trade-offs and epigenetic underpinnings are largely unexplored. A critical challenge is disentangling stable adaptive mechanisms from transient acclimatory shifts. We propose a framework for evaluating drought memory across temporal and generational scales and highlight the potential of precision genome editing to establish causality. By integrating multi-omics, gene editing, and field-based validation, this review aims to unlock the molecular blueprint of drought memory. Understanding these mechanisms is key to engineering climate-resilient crops, ensuring global food security in an era of increasing environmental uncertainty.
Uncovering genetic diversity and population structure of the multipurpose tree species Moringa oleifera: insights from DArTSeq SNP markers
Moringa oleifera, native to the Himalayas and now widespread in the tropics, is valued for its rich nutrient and antioxidant content. Despite its global presence, its genetic diversity remains underexplored. 3968 SNP markers derived from DArTSeq technology were filtered to 1913 informative markers and used to investigate the genetic makeup of Moringa oleifera. Results showed reasonable genetic diversity, with expected heterozygosity ranging from 0.05056 to 0.5008 (average 0.3069). Unweighted neighbour joining phylogeny and principal coordinate analyses identified four geographic clusters: West Africa/Caribbean, East Africa, Southern Africa, and Southeast Asia. Malawi samples clustered distinctly from African samples while Philippine samples clustered separately and farthest, indicating separate introductions. Analysis of Molecular variance showed higher gene flow within populations (77%) than between them (23%). Bayesian modelling in structure confirmed unique clustering in Southern Africa and highlighted significant admixture, suggesting human-mediated introductions. The findings contribute to our understanding of the genetic resources of this important plant species and have implications for germplasm collection, improvement, conservation, utilisation strategies and policies. Further research utilising advanced genomic tools will enhance our knowledge of Moringa oleifera and support its sustainable utilisation for various applications.
Assessing the agroforestry potential of selected native tree species in Rwanda
The deliberate integration of trees into crop and livestock farming systems has garnered significant attention for its ability to deliver environmental, economic, and social benefits. In Rwanda, this agroforestry approach is increasingly embraced because of its capacity to conserve the soil, produce food, feed, and wood products, and provide other essential ecosystem services. However, the limited integration and undervaluation of indigenous tree species in Rwandan farming practices reveal a critical gap in the sustainability of this practice. This study evaluated the agroforestry potential of nine native tree species by examining their compatibility with beans and maize, and their growth outside forest environments. Among the species tested, Pterygota mildbraedii exhibited the highest mean annual height growth (0.27 m yr−1), while Erythrina abyssinica recorded the largest diameter increment (0.30 cm yr−1). Tree presence significantly reduced crop yield (p < 0.05), with compatibility varying among species in the following order: Ficus thonningii, Markhamia platycalyx, Podocarpus falcatus, Maesopsis eminii, and Polyscias fulva. While further studies are needed, these compatibility levels indicate that integrating one or more of the tested species into farming systems may be feasible if the benefits from tree products and ecosystem services outweigh any crop competition.
Integrating molecular genetics with plant breeding to deliver impact
The appropriate use of molecular genetic approaches to reach impact in plant breeding is not straightforward. Here, we consider theory and realized application and explore key issues that early-career plant molecular genetic researchers especially should consider as they establish their careers, particularly in relation to opportunities in plant breeding that span academia and the private sector. Useful entry points for these researchers are an understanding of the plant breeding cycle and the breeder’s equation. Becoming familiar with success and failure factors in the application of molecular genetics to practical plant breeding, including in relation to quantitative genetic principles, is also important. Other framing issues are scenario modeling for choosing between breeding scheme options, how agronomy and plant breeding interrelate, and the needs of future food production systems. We also recommend that early-career plant molecular genetic researchers look at whether pathways have been mapped out for how research will lead to impact at field level, whether stakeholders’ perspectives have been accounted for, and whether the effectiveness of molecular genetic versus alternative interventions have been costed. Early-career researchers should also consider if effective systems are in place to monitor the values of molecular interventions and whether the necessary multidisciplinary teams are involved in crop development and deployment. We believe that through building a cadre of well-informed and well-connected early-career plant molecular genetic researchers, transformational change in the applications of molecular genetics to practical plant breeding will be enhanced.
The History of Wheat Breeding in Afghanistan
Afghanistan is a land-locked country with an area of 65,262,600 hecatares (ha) of which only 7,600,000 ha (11.6%) is cultivable and out of this, only 50% ia arable land. It is characterized by a continental arid and semi-arid climate where the presence of the mountains leads to local climate variations. Temperatures vary from – 10c in winter to 34C in summer. Annual precipitation in most pats of the country ranges between 100-400 mm with an average of 250mm. More than 80% rainfall is received during the winter and early spring. The country is divided into the following six agro-climatic zones.