Peterson, Dawn Bryan, Stephanie Seminars arranged around current issues and controversies in American culture. May be repeated as topic changes. This course considers the history of apocalyptic thinking in United States history.
Received Oct 7; Accepted Oct To view a copy of this license, visit http: Abstract Banana production is severely hindered by plant-parasitic nematodes in acidic, sandy soil.
This study investigated the possibility of applying a novel fumigation agent based on ammonium bicarbonate as a strategy for controlling plant-parasitic nematodes under sealed conditions. Moreover, its effects on the Bacteria morphology lab2 community in pot and field experiments were also measured using morphology and feeding-habit based classification and the PCR-DGGE method.
The nematode community was altered by the different fumigants, and LAB showed an excellent plant-parasitic nematicidal ability, especially for Meloidogyne and Rotylenchulus, as revealed by morphology and feeding-habit based classification, and for Meloidogyne, as revealed by the PCR-DGGE method.
Fungivores and omnivore-predators were more sensitive to the direct effects of the chemicals than bacterivores. This study explored a novel fumigation agent for controlling plant-parasitic nematodes based on LAB and provides a potential strategy to ensure the worldwide development of the banana industry.
Bananas are a staple food because of their high protein content and nutritional value, the main source of income in many developing countries 1and an important food security crop, providing a cheap and easily produced source of energy 2. However, the production of bananas is hampered by many diseases and pests 3including plant-parasitic Bacteria morphology lab2, which are widespread and among the most damaging pests of banana.
Plant-parasitic nematodes cause root damage that not only leads to severe crop losses in commercial banana plantations for export but also seriously limits the production and viability of all banana types 45. More than nematode species of 51 genera have already been documented worldwide on banana 6.
All banana varieties are hosts of root-knot nematodes belonging to the Meloidogyne genus, which attack many economically important crops, cause deformation and stunting of the roots, and are more likely to be found in great numbers on banana roots in the tropics 7.
All bananas are also host to the Pratylenchus, Tylenchus, Ditylenchus and Helicotylenchus genera, which are also major nematode pests and affect banana production across the globe 8.
Thus it is both necessary and urgent to find a better way to ensure healthy banana crops and maintain worldwide development of the industry. To fight banana root nematodes, cultural, biological, physical and chemical control methods are used 9.
However, control options are limited because in most systems of cultivation, bananas are grown as a permanent crop, with no available nematode-resistant varieties 10and no specific nematode control methods are yet practiced in traditional cultivations using nematicides Furthermore, biocontrol is still infeasible, and the effect of mulches on nematode populations is not clear Soil pretreatments, such as soil fumigation with methyl iodide, propargyl bromide, 1, 3-dichloropropene 14calcium cyanamide 15 and methyl bromide, are very effective in suppressing nematode populations However, due to the destruction of soil ecosystems by many of these chemicals, the use of fumigant pesticides is restricted 1718 ; for example, calcium cyanamide is no longer available because of the risks it posses to environmental health 19 Various physical methods, including steam disinfection, soil solarization and hot water injection, have also been employed with varying success for the control of nematodes as alternatives to soil fumigation with synthetic chemicals.
However, many factors, including the soil type, climatic conditions and water content of the soil, can affect the effectiveness of physical treatments Thus, it is necessary to find a better soil pretreatment method. Ammonia has been proved to be responsible for many effects on nematodes: On the other hand, different attraction-repulsion effects produced by ammonia have been reported as a response of entomopathogenic nematodes for seeking a new host 2526 Upon reaction with soil moisture, calcium cyanamide breaks down initially to hydrated lime and hydrogen cyanamide, which then forms ammonia in sequence 28especially ammonia, being reported to reduce the number of nematodes on tomatoes when used as ammonium nutrition The use of bicarbonate salts was not expected to be harmful to humans and the environment Since then, among the ten ammonia-releasing compounds that have been tested, ammonium hydroxide, ammonium phosphate and ammonium bicarbonate have been observed to show the greatest nematicidal activity in pots, and ammonium hydroxide was found to be the most nematicidal of these compounds The enclosure of pots containing ammonia-releasing materials and treated soils in plastic bags reduced the concentration of the materials needed to kill Meloidogyne javanica However, no reports, to our knowledge, have described the effects of soil pretreated with different ammonia production substances as soil fumigants on the banana-parasitic nematode population and the whole nematode community structure, especially in acidic, sandy soils with continuous banana plantings over several years that are seriously infected with plant-parasitic nematodes that harm banana production.
The use of ammonia-releasing materials combined with lime as a soil fumigant to reduce the acidity or increase the alkalinity of the soil has led to interest in these substances as a nematicidal agent.
In this study, several ammonia production materials were evaluated as soil fumigants as an environmentally friendly, safe and long-lasting mean of nematode prevention in acidic, sandy soil in southern China.
The objectives of this study were to compare the effect of several ammonia production substances as soil agents suppressing nematodes, to identify the best nematicide disinfectant, to explore the optimum application mode of the disinfectant, and to investigate the effects of different applied disinfectants on the soil nematode community structure.It allowed us to use real life samples to put down on our slides and view our own bodily bacteria and cells.
Various stages of bacterial morphologies were examined and results were recorded. Procedure: Setting up the microscope. Viewing prepared slides of bacterial morphology%(39). Concept map for Lab 2: Terminology COLONY MORPHOLOGY AND PIGMENTATION A colony is a visible mass of microorganisms growing on an agar surface and usually originating from a single organism or arrangement of organisms.
HOUSTON COMMUNITY COLLEGE - NORTHWEST.
SPRING BRANCH CAMPUS. Course Title: Biology (Microbiology) CRN Days &Times:Mondays/Wednsdays 8 AM to 11 AM. Bacteria Morphology April 2, Abstract – The Purpose of this exercise is to gain experience in bacterial morphologies in prepared wet-mounted slides and interpreting the findings of bacteria through direct and indirect staining technique.
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0 download. Report. Benefit bacteria such as LAB are a group of Gram positive bacteria non-motile characterized by common morphological, physiological and metabolic traits. They performed an essential role in the manufacture and preservation of numerous fermented food products 1.