Project description:The western corn rootworm (WCR, Diabrotica virgifera virgifera LeConte) is an important pest of corn (Zea mays) in the US. Annual crop rotation between corn and soybean (Glycine max) disrupts the corn-dependent WCR lifecycle and was widely adopted to manage WCR. However, this strategy selected for a rotation-resistant (RR) variant with reduced ovipositional fidelity to cornfields. Previous studies indicated that RR-WCR adults exhibit greater tolerance of soybean tissue diet, different gut physiology, and host-microbe interactions compared to wild-types (WT). To identify genetic mechanisms underlying these phenotypic changes, a de novo assembly of the WCR adult gut transcriptome was constructed and used for RNA-sequencing analyses on RNA libraries from different WCR phenotypes (RR and WT) fed with corn or soybean diets. Differential gene expression analyses and network-based methods were used to identify gene modules transcriptionally correlated with the RR phenotype. Gene ontology enrichment analyses on these modules were then conducted to understand their potential functions and biological importance.
Project description:The western corn rootworm (WCR, Diabrotica virgifera virgifera LeConte) is an important pest of corn (Zea mays) in the US. Annual crop rotation between corn and soybean (Glycine max) disrupts the corn-dependent WCR lifecycle and was widely adopted to manage WCR. However, this strategy selected for a rotation-resistant (RR) variant with reduced ovipositional fidelity to cornfields. Previous studies indicated that RR-WCR adults exhibit greater tolerance of soybean tissue diet, different gut physiology, and host-microbe interactions compared to wild-types (WT). To identify genetic mechanisms underlying these phenotypic changes, a de novo assembly of the WCR adult gut transcriptome was constructed and used for RNA-sequencing analyses on RNA libraries from different WCR phenotypes (RR and WT) fed with corn or soybean diets. Differential gene expression analyses and network-based methods were used to identify gene modules transcriptionally correlated with the RR phenotype. Gene ontology enrichment analyses on these modules were then conducted to understand their potential functions and biological importance. Differential gene expression analyses on RNA libraries from adult guts of different WCR phenotypes (rotation-resistant and wild-type) fed with corn or soybean diets
Project description:Transcriptional profiling of sweet corn response to plant density (crowding stress). Determine the extent to which hybrid and environment influences crowding stress response and identify crowding stress transcriptional response in sweet corn
Project description:This study was designed to identify changes in gene expression that occur when corn was grown on different landscape features. Specifically on the backslope or summit/shoulder of a hill. In rolling landscapes, plant available water varies drastically by location and soil type. Almost simultaneously, plants may be flooded out in footslope locations whereas plants in summit locations may be suffering from severe drought. The objective of this study was to determine the influence of landscape position on corn (Zea mays) productivity and gene regulation. Corn was sampled at V12 for plant growth characteristics and transcriptome analysis at summit/shoulder and lower backslope positions. Plants at the summit had 16% less leaf area and biomass compared with plants at the toeslope. Gene expression analysis using microarray chips, transcriptome analysis, and qPCR indicated that plants at the summit had 708 genes down-regulated and 399 genes up-regulated compared to control plants at the lower back slope. GSEA (Gene Set Enrichment Analysis) indicated tolerance to cold, salt, and drying were increased in summit/should plants compared to control toeslope plants. However, nutrient uptake, recovery from wounding, pest and fungal disease resistance, along with photosynthetic capacity were all down-regulated in moderate water stresses plants. These responses suggest that corn preferentially responses to water stress as the expense of its ability to respond to other stresses.
Project description:This study was designed to look for differential gene expression in the annual dicot weed velvetleaf when it is grown in competition with corn relative to when it is grown in monoculture. Keywords: weed/crop competition
Project description:Transcriptional profiling of sweet corn plant density (crowding stress) tolerance influencing yield. Tolerance to crowding stress has played a crucial role in improving agronomic productivity in field corn; however, commercial sweet corn hybrids vary greatly in crowding stress tolerance. The experiment was conducted to 1) explore transcriptional changes among sweet corn hybrids with differential yield under crowding stress, 2) identify relationships between phenotypic responses and gene expression patterns, and 3) identify groups of genes associated with yield and crowding stress tolerance. Under conditions of crowding stress, three high-yielding and three low-yielding sweet corn hybrids were grouped for transcriptional and phenotypic analyses. Transcriptional analyses identified from 372 to 859 common differentially expressed genes (DEGs) for each hybrid. Large gene expression pattern variation among hybrids and only 26 common DEGs across all hybrid comparisons were identified, suggesting each hybrid has a unique response to crowding stress. Over-represented biological functions of DEGs also differed among hybrids. Strong correlation was observed between: 1) modules with up-regulation in high-yielding hybrids and yield traits, and 2) modules with up-regulation in low-yielding hybrids and plant/ear traits. Modules linked with yield traits may be important crowding stress response mechanisms influencing crop yield. Functional analysis of the modules and common DEGs identified candidate crowding stress tolerant processes in photosynthesis, glycolysis, cell wall, carbohydrate/nitrogen metabolic process, chromatin, and transcription regulation. Moreover, these biological functions were greatly inter-connected, indicating the importance of improving the mechanisms as a network.