Biology subjects

Hutmacher, R.

Publications and source records attributed to Hutmacher, R..

4 recordsLinked to original sources

bioRxiv2025

Multi-season analysis reveals hundreds of drought-responsive genes in sorghum

Persistent drought affects global crop production and is becoming more severe in many parts of the world in recent decades. Deciphering how plants respond to drought will facilitate the development of flexible mitigation strategies. Sorghum bicolor L. Moench (sorghum), a major cereal crop and an emerging bioenergy crop, exhibits remarkable resilience to drought. To better understand the molecular traits that underlie sorghums remarkable drought tolerance, we undertook a large-scale sorghum gene expression profiling effort, totaling nearly 1,500 transcriptome profiles, across a 3-year field study with replicated plots in Californias Central Valley. This study included time-resolved gene expression data from roots and leaves of two sorghum genotypes, BTx642 and RTx430, with different pre-flowering and post-flowering drought-tolerance adaptations under control and drought conditions. Quantification of genotype-specific drought tolerance effects was enabled by de novo sequencing, assembly, and annotation of both BTx642 and RTx430 genomes. These reference-quality genomes were used to construct a pan-gene set for characterizing conserved and genotype-specific expression. By integrating time-resolved transcriptomic responses to drought in the field across three consecutive years, we identified a set of drought-responsive genes that responded similarly in all three years of our field study. This expansive dataset represents a unique resource for sorghum and drought research communities and provides a methodological framework for the integration of multi-faceted time-resolved transcriptomic datasets.

genomics↗

bioRxiv2024

A proposed framework for evaluating meat alternatives

Concerns surrounding the environmental, economic, and ethical consequences of meat production and industrial agriculture have prompted substantial research and capital investment into the production of meat alternatives. Alternative meat production encompasses a variety of technological approaches including plant-based meats, cell-based or cultivated meats, meat alternatives relying on fungal protein sources, and hybrids thereof; each of which offers unique advantages and disadvantages and has been associated with a myriad of claims supporting it as the preferred alternative to animal-derived meats. As part of XPRIZE Foundations Feed the Next Billion competition, we developed a framework for evaluating meat alternatives by measuring their structural, nutritional, and organoleptic properties while also assessing safety and their purported environmental and economic benefits compared to animal-derived meats. The framework is technologically agnostic and can be used to evaluate meat alternatives of all types. The output of the framework enables a data-driven comparison to animal-derived meat and/or other alternative meats, allowing a range of stakeholders (e.g., food startups, investors, government) to assess technological readiness, competitive advantage, and impact potential. This framework can assist this nascent industry as it moves towards standardizing approaches to evaluating the quality, safety and proposed benefits of meat alternatives.

bioengineering↗

bioRxiv2023

Defined synthetic microbial communities colonize and benefit field-grown sorghum

The rhizosphere represents a dynamic and complex interface between plant hosts and the microbial community found in the surrounding soil. While it is recognized that manipulating the rhizosphere has the potential to improve plant fitness and health, engineering the rhizosphere microbiome through inoculation has often proved challenging. This is in large part due to the competitive microbial ecosystem in which the added microbes must survive, and lack of adaptation of these added microbes to the specific metabolic and environmental pressures of the rhizosphere. Here, we constructed an inoculation formula using a defined synthetic community (dSynCom) approach that we hypothesized would improve engraftment efficiency and potentially the relationship with the host plant, Sorghum bicolor. The dSynCom was assembled from bacterial isolates that were either: 1) identified to potentially play a role in community cohesion through network analysis, or 2) identified to benefit from host-specific exudate compounds. Growth of the dSynCom was first evaluated in vitro on solid media, secondly in planta under gnotobiotic laboratory conditions, and finally using sorghum plants grown in the field. We demonstrate that the dSynCom performs best in terms of maintaining diversity when grown in the presence of the plant host in lab conditions, and that many lineages are lost from the community when grown either in vitro or in a native field setting. Finally, we demonstrate that the dSynCom is able to promote growth of above- and below-ground plant phenotypes compared to uninoculated controls, both in the lab and when applied to plants grown in the field. These results demonstrate the potential utility of SynComs for supporting crop performance even in the absence of persistence, and the need for a deeper mechanistic understanding of community control of host fitness in agricultural contexts.

synthetic biology↗

bioRxiv2022

Metabolomic, photoprotective, and photosynthetic acclimatory responses to post-flowering drought in sorghum

Climate change is globally affecting rainfall patterns, necessitating the improvement of drought tolerance in crops. Sorghum bicolor is a drought-tolerant cereal capable of producing high yields under water scarcity conditions. Functional stay-green sorghum genotypes can maintain green leaf area and efficient grain filling in terminal post-flowering water deprivation, a period of ~10 weeks. To obtain molecular insights into these characteristics, two drought-tolerant genotypes, BTx642 and RTx430, were grown in control and terminal post-flowering drought field plots in the Central Valley of California. Photosynthetic, photoprotective, water dynamics, and biomass traits were quantified and correlated with metabolomic data collected from leaves, stems, and roots at multiple timepoints during drought. Physiological and metabolomic data was then compared to longitudinal RNA sequencing data collected from these two genotypes. The metabolic response to drought highlights the uniqueness of the post-flowering drought acclimation relative to pre-flowering drought. The functional stay-green genotype BTx642 specifically induced photoprotective responses in post-flowering drought supporting a putative role for photoprotection in the molecular basis of the functional stay-green trait. Specific genes are highlighted that may contribute to post-flowering drought tolerance and that can be targeted in crops to maximize yields under limited water input conditions. HighlightPathways contributing to the long-term maintenance of photosynthetic activity in terminal post-flowering drought are revealed by a comprehensive approach combining in-field photosynthetic physiological analysis, metabolomics, and transcriptomics.

plant biology↗