The maize rachis affects Aspergillus flavus spread during ear development

Aspergillus flavus that transgenically expressed the green fluorescent protein was used to follow infection in ears of maize hybrids resistant and susceptible to the fungus. Developing ears were needle-inoculated with GFP- transformed A. flavus 20 days after silk emergence, and GFP fluorescence in the pith was evaluated at 1, 2, 3, 4, 5, 10, and 20 days after inoculation. Fluorescence levels in the pith of susceptible lines were significantly higher (P < 0.0001) than in resistant lines at all time points. Pith sections apical to the inoculation point displayed higher fluorescence levels compared to other sections of the ear, suggesting fungal spread via the water/nutrient transport system. Fluorescence levels in resistant lines did not change significantly over time, implying spread of the fungus but not growth. Fluorescence in susceptible ears was highest at early time points, suggesting that conditions were more conducive to spread than at the later time points. These results suggest that the rachis could retard the spread and/or growth of the fungus inside the developing maize ear. Although fluorescence was observed in kernels from resistant ears, it occurred at a much higher frequency in those from susceptible hybrids. Together, these results suggest that the rachis is used by maize as a defense structure similar to other preformed types of resistance

Intraplant communication in maize contributes to defense against insects

The vasculature of plants act as a channel for transport of signal(s) that facilitate long-distance intraplant communication. In maize, Maize insect resistance1-Cysteine Protease (Mir1-CP), which has homology to papain-like proteases, provides defense to different feeding guilds of insect pests. Furthermore, accumulation of Mir1-CP in the vasculature suggests that Mir1-CP can potentially function as a phloemmobile protein. In a recent study, we provided evidence that Mir1-CP can curtail the growth of phloemsap sucking insect, corn leaf aphid (CLA; Rhopalosiphum maidis). Our current study further examined whether aboveground feeding by CLA can induce resistance to subsequent herbivory by belowground feeding western corn rootworm (WCR; Diabrotica virgifera virgifera). Aboveground feeding by CLA systemically induced the accumulation of Mir1-CP in the roots. Furthermore, foliage feeding by CLA provided enhanced resistance to subsequent herbivory by below ground feeding of WCR. Taken together, our previous findings and results presented here indicate that long-distance transport of Mir1-CP is critical for providing enhanced resistance to insect attack in maize

Intraplant communication in maize contributes to defense against insects

The vasculature of plants act as a channel for transport of signal(s) that facilitate long-distance intraplant communication. In maize, Maize insect resistance1-Cysteine Protease (Mir1-CP), which has homology to papain-like proteases, provides defense to different feeding guilds of insect pests. Furthermore, accumulation of Mir1-CP in the vasculature suggests that Mir1-CP can potentially function as a phloemmobile protein. In a recent study, we provided evidence that Mir1-CP can curtail the growth of phloemsap sucking insect, corn leaf aphid (CLA; Rhopalosiphum maidis). Our current study further examined whether aboveground feeding by CLA can induce resistance to subsequent herbivory by belowground feeding western corn rootworm (WCR; Diabrotica virgifera virgifera). Aboveground feeding by CLA systemically induced the accumulation of Mir1-CP in the roots. Furthermore, foliage feeding by CLA provided enhanced resistance to subsequent herbivory by below ground feeding of WCR. Taken together, our previous findings and results presented here indicate that long-distance transport of Mir1-CP is critical for providing enhanced resistance to insect attack in maize

AgBase: a unified resource for functional analysis in agriculture

Analysis of functional genomics (transcriptomics and proteomics) datasets is hindered in agricultural species because agricultural genome sequences have relatively poor structural and functional annotation. To facilitate systems biology in these species we have established the curated, web-accessible, public resource ‘AgBase’ (). We have improved the structural annotation of agriculturally important genomes by experimentally confirming the in vivo expression of electronically predicted proteins and by proteogenomic mapping. Proteogenomic data are available from the AgBase proteogenomics link. We contribute Gene Ontology (GO) annotations and we provide a two tier system of GO annotations for users. The ‘GO Consortium’ gene association file contains the most rigorous GO annotations based solely on experimental data. The ‘Community’ gene association file contains GO annotations based on expert community knowledge (annotations based directly from author statements and submitted annotations from the community) and annotations for predicted proteins. We have developed two tools for proteomics analysis and these are freely available on request. A suite of tools for analyzing functional genomics datasets using the GO is available online at the AgBase site. We encourage and publicly acknowledge GO annotations from researchers and provide an online mechanism for agricultural researchers to submit requests for GO annotations

Efeito de glifosato em lipoxigenase de semente de caupi (Vigna unguiculata (L.) Walp.).

A atividade máxima de lipoxigenase em sementes de caupi (Vigna unguiculata (L.) Walp.) foi obtida com cálcio a 0,68 mM e pH 7.5. Sementes foram analisadas durante a germinação e a atividade especifica de lipoxigenase diminuiu durante o processo. Sementes de plantas tratadas com o herbicida glifosato [N - (fosofonometil) glicina] como dessecante, mostraram significante aumento da atividade especifica de lipooxigenase. Isto pode ser resultado do efeito do herbicida nas plantas. Tal conclusao e baseada no fato de que lipoxigenase, que teve sua atividade especifica aumentada pelo glifosato, pode promover a formação do ácido 12-oxo-fitodienoico que por sua vez É um possível precursor do acido jasmônico, um regulador de crescimento que promove senescência em plantas, explicando desta maneira a ação do herbicida nas mesmas. Pelo método utilizado, não foi encontrada a enzima em folhas ou outras partes verdes das plantas

OPDA regulates maize defense against aphids

Copyright © 2019 American Society of Plant Biologists. DOI:10.1104/pp.18.0147

AgBase: a functional genomics resource for agriculture

BACKGROUND: Many agricultural species and their pathogens have sequenced genomes and more are in progress. Agricultural species provide food, fiber, xenotransplant tissues, biopharmaceuticals and biomedical models. Moreover, many agricultural microorganisms are human zoonoses. However, systems biology from functional genomics data is hindered in agricultural species because agricultural genome sequences have relatively poor structural and functional annotation and agricultural research communities are smaller with limited funding compared to many model organism communities. DESCRIPTION: To facilitate systems biology in these traditionally agricultural species we have established "AgBase", a curated, web-accessible, public resource for structural and functional annotation of agricultural genomes. The AgBase database includes a suite of computational tools to use GO annotations. We use standardized nomenclature following the Human Genome Organization Gene Nomenclature guidelines and are currently functionally annotating chicken, cow and sheep gene products using the Gene Ontology (GO). The computational tools we have developed accept and batch process data derived from different public databases (with different accession codes), return all existing GO annotations, provide a list of products without GO annotation, identify potential orthologs, model functional genomics data using GO and assist proteomics analysis of ESTs and EST assemblies. Our journal database helps prevent redundant manual GO curation. We encourage and publicly acknowledge GO annotations from researchers and provide a service for researchers interested in GO and analysis of functional genomics data. CONCLUSION: The AgBase database is the first database dedicated to functional genomics and systems biology analysis for agriculturally important species and their pathogens. We use experimental data to improve structural annotation of genomes and to functionally characterize gene products. AgBase is also directly relevant for researchers in fields as diverse as agricultural production, cancer biology, biopharmaceuticals, human health and evolutionary biology. Moreover, the experimental methods and bioinformatics tools we provide are widely applicable to many other species including model organisms

Multicentre performance evaluation of the E170 Module for MODULAR ANALYTICS

The E170 module was evaluated at 13 sites in an international multicentre study. The objective of the study was to assess the analytical performance of 49 analytes, and to collect feedback on the system's reliability and practicability. The typical, within-run coefficients of variation (CVs) for most of the quantitative assays ranged between 1 and 2% while a range of 2-4% was achieved with the infectious disease methods. Total precision CVs were found to be within the manufacturer's expected performance ranges, demonstrating good concordance of the system's measuring channels and a high reproducibility during the 2-4-week trial period. The functional sensitivity of 11 selected assays met the clinical requirements (e.g., thyreotroponin (TSH) 0.008 mU/l, troponin T 0.02 µg/l, total prostate-specific antigen (PSA) 0.03 µg/l). The E170 showed no drift during an 8-hour period and no relevant reagent carryover. Accuracy was confirmed by ring trial experiments and method comparisons vs. Elecsys® 2010. The reliability and practicability of the system's hardware and software met with, or even exceeded, the evaluator's requirements. Workflow studies showed that E170 can cover the combined workload of various routine analysers in a variety of laboratory environment. Throughput and sample processing time requirements were achieved while personnel ‘hands-on-time' could be reduce