Exploring RNA interference in the agricultural pests western corn rootworm, fall armyworm, and southern green stink bug

RNA interference (RNAi) is a highly conserved cellular process whereby small regulatory RNAs bound to argonaute proteins produce sequence-specific silencing of longer complementary RNAs. The agricultural biotechnology industry has taken advantage of RNAi to control insect pests through the use of transgenic crops expressing insecticidal RNAs. Upon introduction of double-stranded RNA into a pest, the complementary target messenger RNA is depleted and results in a lethal phenotype. For reasons that are not fully defined, certain insects respond differently to orally introduced RNAs, leaving holes in the manageability of all agricultural pests through this promising new technology. Furthermore, there are indications that insects may be able to develop resistance to crop-mediated RNAi through natural downregulation of RNAi pathway genes, among other proposed mechanisms. Using bioinformatics, next-generation sequencing, and insect bioassays, eight genes essential for RNAi were examined in three important agricultural insect pests for their potential involvement both in the differing responses to exogenous RNAs observed across these insects, and in development of resistance to insecticidal RNAs. These genes include drosha, dicer-1, dicer-2, pasha, loquacious, r2d2, argonaute 1, and argonaute 2. Putative homologues of the well-characterized Drosophila melanogaster genes were identified in the western corn rootworm (Diabrotica virgifera virgifera), fall armyworm (Spodoptera frugiperda), and southern green stink bug (Nezara viridula) and compared using translated gene products. All genes were present in each insect and most showed conservation of basic protein domain structure, but differences in the number of isoforms and expression level of pasha, loquacious, r2d2, argonaute 1, and argonaute 2 were found. Sequencing experiments in each insect revealed the presence of small RNAs typical of the products of RNAi pathways, including conserved microRNAs. Abundance and distribution of these RNAs varied across life stage and insect. Finally, transcript depletion experiments were conducted in rootworm, and adverse phenotypic effects for each gene were observed. Taken together, these results suggest that while differences in these eight genes could contribute to variation in the RNAi pathways of these insects and therefore to variation in response to exogenous RNAs, they are unlikely to promote development of resistance to RNAi-based technology through expression pattern changes

An Evening of Samuel Beckett

Productions took place September 28-30 October 2-7https://ir.library.illinoisstate.edu/sotdp/1070/thumbnail.jp

Quantitative trait loci for seminal root angle and number in the maize IBM population

Abstract only availableIn maize, seminal roots develop and the primary root system deteriorates as the plant matures. The seminal roots comprise the majority of the root system of the adult plant and give the plant stability against lodging. Because seminal roots are the primary means of water uptake in the adult plant, their development under drought conditions is vital. Previous research has suggested that seminal root angle and abscisic acid (ABA) level are correlated in maize. Additional research has shown that ABA levels are related to drought tolerance. This study focuses on identifying quantitative trait loci (QTL) that affect seminal root angle and the number of seminal roots entering the soil from each node. The QTL generated for seminal root angle and number per node can then be used to evaluate the relationship with drought tolerance. A set of 94 mapping lines from the intermated B73 x Mo17 (IBM) mapping population was used to measure the angle between the seminal root and the stalk. The number of seminal roots entering the soil from the first two nodes was measured as well. Molecular markers evenly distributed throughout the genome were used to run the QTL analysis using QTL Cartographer Version 1.16. The following QTL analyses were run: seminal root angle, number of roots entering soil from the first node above ground, and number of roots entering soil from the second node. Three QTL were found for seminal root angle, two QTL for the number of roots at the first node above ground, and three QTL for the number of roots at the second node above ground. These QTL positions were then compared to previously known QTL for drought tolerance and root traits.Plant Genomics Internship @ M

Environmental Factors Influencing Drinking Water Consumption and Access in Rural Communities: Cuba, New Mexico

Consumption of sugar sweetened beverages (SSBs) contributes to increasing obesity rates because they are a highly caloric beverage with poor nutritional value. Substituting SSB consumption with water consumption will help to decrease obesity. Water consumption is affected by various factors, including water access, a clean water supply, SSB popularity, policies, recommendations, and individual perceptions. Little research has addressed water consumption in rural populations. We are investigating access to drinking water of residents of the rural multicultural town of Cuba, NM. A literature review is being conducted on the advantages of water consumption and adverse effects of SSBs. Field observations assessed access to water and water quality in schools. Federal, state and local requirements for water in schools are being reviewed. A modified version of the Nutrition Environment Measurements Survey will assess the availability and pricing of water in comparison to that of SSBs. An analysis of a transcribed meeting on community water consumption will provide information on the knowledge, behaviors, and attitudes of community members regarding their water supply and consumption rates. A geographic information system map will be used to document water sources and quality as previously determined by annual tests (2004-14). Our findings should provide information on environmental factors influencing water consumption in Cuba that inform development of a community guide to facilitate discussions about increasing water consumption in that community. This information will also contribute to research on increasing drinking water consumption in other rural communities.https://digitalrepository.unm.edu/prc-posters-presentations/1010/thumbnail.jp