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Abstract Arbuscular mycorrhizal symbiosis (AM) is a beneficial trait originating with the first land plants, which has subsequently been lost by species scattered throughout the radiation of plant diversity to the present day, including the modelArabidopsis thaliana. To explore if elements of this apparently beneficial trait are still present and could be reactivated we generatedArabidopsisplants expressing a constitutively active form ofInteracting Protein of DMI3, a key transcription factor that enables AM within the Common Symbiosis Pathway, which was lost fromArabidopsisalong with the AM host trait. We characterize the transcriptomic effect of expressingIPD3inArabidopsiswith and without exposure to the AM fungus (AMF)Rhizophagus irregularis, and compare these results to the AM modelLotus japonicusand itsipd3knockout mutantcyclops-4. Despite its long history as a non-AM species, restoringIPD3in the form of its constitutively active DNA-binding domain toArabidopsisaltered expression of specific gene networks. Surprisingly, the effect of expressingIPD3inArabidopsisand knocking it out inLotuswas strongest in plants not exposed to AMF, which is revealed to be due to changes inIPD3genotype causing a transcriptional state, which partially mimics AMF exposure in non-inoculated plants. Our results indicate that molecular connections to symbiosis machinery remain in place in this nonAM species, with implications for both basic science and the prospect of engineering this trait for agriculture. 

Abstract Circular RNAs (circRNAs) are covalently closed single‐stranded RNAs, generated through a back‐splicing process that links a downstream 5′ site to an upstream 3′ end. The only distinction in the sequence between circRNA and their linear cognate RNA is the back splice junction. Their low abundance and sequence similarity with their linear origin RNA have made the discovery and identification of circRNA challenging. We have identified almost 6000 novel circRNAs fromLotus japonicusleaf tissue using different enrichment, amplification, and sequencing methods as well as alternative bioinformatics pipelines. The different methodologies identified different pools of circRNA with little overlap. We validated circRNA identified by the different methods using reverse transcription polymerase chain reaction and characterized sequence variations using nanopore sequencing. We compared validated circRNA identified inL. japonicusto other plant species and showed conservation of high‐confidence circRNA‐expressing genes. This is the first identification ofL. japonicuscircRNA and provides a resource for further characterization of their function in gene regulation. CircRNAs identified in this study originated from genes involved in all biological functions of eukaryotic cells. The comparison of methodologies and technologies to sequence, identify, analyze, and validate circRNA from plant tissues will enable further research to characterize the function and biogenesis of circRNA inL. japonicus. 

Abstract Public concern regarding the use of herbicides in urban areas (e.g., golf courses, parks, lawns) is increasing. Thus, there is a need for alternative methods for weed control that are safe for the public, effective against weeds, and yet selective to turfgrass and other desirable species. New molecular tools such as ribonucleic acid interference (RNAi) have the potential to meet all those requirements, but before these technologies can be implemented, it is critical to understand the perceptions of key stakeholders to facilitate adoption as well as regulatory processes. With this in mind, turfgrass system managers, such as golf course superintendents and lawn care providers, were surveyed to gain insight into the perception and potential adoption of RNAi technology for weed management. Based on survey results, turfgrass managers believe that cost of weed management and time spent managing weeds are the main challenges faced in their fields. When considering new weed management tools, survey respondents were most concerned about cost, efficacy, and efficiency of a new product. Survey respondents were also optimistic toward RNAi for weed management and would either use this technology in their own fields or be willing to conduct research to develop RNAi herbicides. Although respondents believed that the general public would have some concerns about this technology, they did not believe this to be the most important factor for them when choosing new weed management tools. The need for new herbicides to balance weed control challenges and public demands is a central factor for turfgrass managers’ willingness to use RNAi-based weed control in turfgrass systems. They believe their clientele will be accepting of RNAi tools, although further research is needed to investigate how a wider range of stakeholders perceive RNAi tools for turfgrass management more broadly. 

The evolution of pest resistance to management tools reduces productivity and results in economic losses in agricultural systems. To slow its emergence and spread, monitoring and prevention practices are implemented in resistance management programs. Recent work suggests that genomic approaches can identify signs of emerging resistance to aid in resistance management. Here, we empirically examined the sensitivity of genomic monitoring for resistance management in transgenic Bt crops, a globally important agricultural innovation. Whole genome resequencing of wild North AmericanHelicoverpa zeacollected from non-expressing refuge and plants expressing Cry1Ab confirmed that resistance-associated signatures of selection were detectable after a single generation of exposure. Upon demonstrating its sensitivity, we applied genomic monitoring to wildH. zeathat survived Vip3A exposure resulting from cross-pollination of refuge plants in seed-blended plots. Refuge seed interplanted with transgenic seed exposedH. zeato sublethal doses of Vip3A protein in corn ears and was associated with allele frequency divergence across the genome. Some of the greatest allele frequency divergence occurred in genomic regions adjacent to a previously described candidate gene for Vip3A resistance. Our work highlights the power of genomic monitoring to sensitively detect heritable changes associated with field exposure to Bt toxins and suggests that seed-blended refuge will likely hasten the evolution of resistance to Vip3A in lepidopteran pests. 

The purpose of this study was to determine the training needs of extension agents in Uganda to lead successful education programs on genetically engineered (GE) crops. This was a descriptive survey research study conducted online with public agricultural extension agents in the eastern agro-ecological zone of Uganda. This study used Borich’s method to identify training needs. A survey instrument was designed to determine extension agents’ perceived importance and proficiency of 60 competencies organized under the eight Public Issues Education (PIE) framework competency constructs. The survey received 58 usable responses comprising an 83% response rate. All eight PIE competency constructs were perceived by the extension agents to be important. This study identified additional four competencies important for PIE in addition to the eight competencies in the model. Agents’ greatest training needs were creating partnerships and designing GE education programs. The lowest training needs were creating an environment of professionalism and managing conflicts. The findings indicate the importance of training extension agents on how to engage with farmers in new ways to educate them on GE technology. This study provides implications for determining the training needs of extension agents in PIE such as educating farmers on GE technology. 

Bioengineered/genome-edited carbon capture and sequestration (BE/GEd-CCS) crops are being developed to mitigate climate change. This paper explores how technology, regulation, funding, and social implications, could shape the development and deployment of these crops. We conclude that some of the technological efforts to create BE/GEd-CCS crops may work. Still, stakeholders must agree on generally accepted methods of measuring how much carbon is captured in the soil and its value. The regulatory space for BE/GEd-CCS crops remains fluid until the first crops are reviewed. BE/GEd-CCS crops have received considerable initial funding and may benefit financially more from other federal programs and voluntary carbon markets. BE/GEd-CCS crops may continue perpetuating social equity concerns about agricultural biotechnology due to a lack of oversight. We argue that stakeholders need to pursue a multidisciplinary view of BE/GEd-CCS crops that draw in varying perspectives for effective development and deployment. Communication is needed between researchers and policymakers involved in either developing BE/GEd-CCS crops or developing voluntary carbon markets. We argue for the start of a conversation both across disciplines and between researchers and policymakers about the development and deployment of BE/GEd-CCS crops. 

A growing bioeconomy must prioritize new forms of public engagement and transparency.