Methods for extracting plant pathogenic nematodes from Brachiaria seed
ABSTRACT A commonly used forage grass in Brazil is Brachiaria spp. These grasses are used as feed for beef and cattle production and are grown on approximately 70 million hectares in Brazil. A pasture with Brachiaria spp. can last for 20 years and is relatively free from diseases. Two of the p...
| Autor principal: | |
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| Formato: | Second cycle, A2E |
| Lenguaje: | sueco Inglés |
| Publicado: |
2015
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| Materias: | |
| Acceso en línea: | https://stud.epsilon.slu.se/8453/ |
| _version_ | 1855571354070286336 |
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| author | Jonsson, Agnes |
| author_browse | Jonsson, Agnes |
| author_facet | Jonsson, Agnes |
| author_sort | Jonsson, Agnes |
| collection | Epsilon Archive for Student Projects |
| description | ABSTRACT
A commonly used forage grass in Brazil is Brachiaria spp. These grasses are used
as feed for beef and cattle production and are grown on approximately 70 million
hectares in Brazil. A pasture with Brachiaria spp. can last for 20 years and is relatively
free from diseases. Two of the pathogens that do attack Brachiaria spp. are
the nematodes Aphelenchoides besseyi and Ditylenchus dipsaci. These nematodes
are seed-borne and affect the host plant by eating of the plants growing parts of
stems and leaves. As the plant matures, the nematodes move to the seeds where
they overwinter or stay until the seeds get in contact with moisture. Both A. besseyi
and D. dipsaci can survive in the seeds in a dry state for several years. Both of these
nematodes are classified as quarantine pests due to the damage they cause on their
host plants and economically. To stop the spreading of A. besseyi and D. dipsaci,
chemical or hot water treatments are used to control the nematodes. In Sweden, a
company called Incotec Sweden AB has developed a method for treating seedborne
diseases, named ThermoSeed. This treats the seeds with different intensities
of steam. To evaluate their treatment, a method to extract nematodes from Brachiaria
seed is needed to be able to guarantee seeds without living nematodes. The
purpose of this master thesis was to find a method for extracting nematodes from
Brachiaria ruzizensis seed that is fast, reliable and cost effective. Four different
methods were tested: the Baermann funnel method, a method developed by Zuckermann
et al., a method developed by Coolen and D’Herde and The simple method
developed by Hoshino and Togashi. To test the methods, three types of treated
seeds were used. Untreated seed (positive control), treated seeds with Incotec
treatment and negative control (seeds that have been treated multiple times with
high steam intensity). The methods were analyzed by counting the recovered nematodes
from each of the methods. The data collected were analyzed statistically with
ANOVA and a following post hoc Tukey test. From these analyses it was concluded
that the Baermann funnel was the method which extracted the most nematodes
from the untreated seeds compared to the other methods. The Baermann funnel
method also gave clear samples and was easy to conduct. |
| format | Second cycle, A2E |
| id | RepoSLU8453 |
| institution | Swedish University of Agricultural Sciences |
| language | Swedish Inglés |
| publishDate | 2015 |
| publishDateSort | 2015 |
| record_format | eprints |
| spelling | RepoSLU84532015-09-03T07:56:59Z https://stud.epsilon.slu.se/8453/ Methods for extracting plant pathogenic nematodes from Brachiaria seed Jonsson, Agnes Pests of plants Plant diseases ABSTRACT A commonly used forage grass in Brazil is Brachiaria spp. These grasses are used as feed for beef and cattle production and are grown on approximately 70 million hectares in Brazil. A pasture with Brachiaria spp. can last for 20 years and is relatively free from diseases. Two of the pathogens that do attack Brachiaria spp. are the nematodes Aphelenchoides besseyi and Ditylenchus dipsaci. These nematodes are seed-borne and affect the host plant by eating of the plants growing parts of stems and leaves. As the plant matures, the nematodes move to the seeds where they overwinter or stay until the seeds get in contact with moisture. Both A. besseyi and D. dipsaci can survive in the seeds in a dry state for several years. Both of these nematodes are classified as quarantine pests due to the damage they cause on their host plants and economically. To stop the spreading of A. besseyi and D. dipsaci, chemical or hot water treatments are used to control the nematodes. In Sweden, a company called Incotec Sweden AB has developed a method for treating seedborne diseases, named ThermoSeed. This treats the seeds with different intensities of steam. To evaluate their treatment, a method to extract nematodes from Brachiaria seed is needed to be able to guarantee seeds without living nematodes. The purpose of this master thesis was to find a method for extracting nematodes from Brachiaria ruzizensis seed that is fast, reliable and cost effective. Four different methods were tested: the Baermann funnel method, a method developed by Zuckermann et al., a method developed by Coolen and D’Herde and The simple method developed by Hoshino and Togashi. To test the methods, three types of treated seeds were used. Untreated seed (positive control), treated seeds with Incotec treatment and negative control (seeds that have been treated multiple times with high steam intensity). The methods were analyzed by counting the recovered nematodes from each of the methods. The data collected were analyzed statistically with ANOVA and a following post hoc Tukey test. From these analyses it was concluded that the Baermann funnel was the method which extracted the most nematodes from the untreated seeds compared to the other methods. The Baermann funnel method also gave clear samples and was easy to conduct. SAMMANFATTNING Ett vanligt förekommande fodergräs i Brasilien är släktet Brachiaria spp. Detta gräs odlas idag på ca 70 miljoner hektar vilket kan sättas i perspektiv med Sveriges totala jordbruksmark som är ca 2.6 miljoner hektar. En vall med Brachiaria kan leva i upp till 20 år och behöver varken mycket gödsling eller vatten för att överleva. Det är ett relativt friskt gräs med få sjukdomar. Två av de patogener som dock kan angripa Brachiaria är de växtpatogena nematoderna Aphelenchoides besseyi och Ditylenchus dipsaci. Dessa nematoder är fröburna och påverkar värdväxten genom att äta av växtens växande delar av stammar och blad. När växten mognar förflyttar sig nematoderna till fröna och stannar där tills fröna har mognat. Både A. besseyi och D. dipsaci kan överleva i ett torkat stadie i fröna i ett flertal år. När fröna kommer i kontakt med fukt återfuktas även nematoderna som sedan börjar äta av växtens groende delar. Detta påverkar frönas grobarhet och föryngring av vallen. Dessa nematoder bedöms göra så stor åverkan på dess värdväxter och ur en ekonomisk aspekt att de klassas som karantänskadegörare. För att förhindra spridning av dessa nematoder behandlas idag fröerna kemiskt eller genom varmvattenbehandling. I Sverige har företaget Incotec Sweden AB utvecklat en metod att behandla utsädesburna sjukdomar som kallas ThermoSeed. Denna behandling går ut på att behandla frön med olika intensitet av ånga. För att kunna veta hur bra behandlingen funkar behövs en metod för att driva ut eventuella levande nematoder ur fröna. Detta masterarbete hade som mål att hitta en metod för att driva ut nematoder ur Brachiara frön på ett enkelt, snabbt och pålitligt sätt. I detta arbete testades fyra olika metoder för utdrivning av nematoder med ett obehandlat fröparti, ett behandlat av Incotec och ett parti som garanterat inte innehåller några levande nematoder (negativ kontroll). De fyra metoderna som testades var Baermann- trattar, en metod utvecklad av Zuckermann et al., en metod utvecklad av Coolen och D’Herde och ”The simple method” utvecklad av Hoshino och Tagashi. Metoderna analyserades genom att räkna hur många nematoder totalt som drivats ut med respektive metod. Därefter jämfördes metoderna statistiskt med ANOVA följt av Tukey post hoc analys. Från analyserna kunde konstateras att Baermann-trattmetoden skiljde sig signifikant från de andra metoderna med fler utdrivna nematoder än de andra. Det var även denna metod som gav klarast prov och därför var enklast att analysera. Som slutsats kan konstateras att för detta syfte, att hitta en metod som snabbt, enkelt och pålitligt driver ut nematoder, är Baermann-tratt metoden den av de testade metoderna bästa. 2015-09-01 Second cycle, A2E NonPeerReviewed application/pdf sv https://stud.epsilon.slu.se/8453/1/jonsson_a_150901.pdf Jonsson, Agnes, 2015. Methods for extracting plant pathogenic nematodes from Brachiaria seed. Second cycle, A2E. Uppsala: (NL, NJ) > Dept. of Ecology <https://stud.epsilon.slu.se/view/divisions/OID-415.html> urn:nbn:se:slu:epsilon-s-4809 eng |
| spellingShingle | Pests of plants Plant diseases Jonsson, Agnes Methods for extracting plant pathogenic nematodes from Brachiaria seed |
| title | Methods for extracting plant pathogenic nematodes from Brachiaria seed |
| title_full | Methods for extracting plant pathogenic nematodes from Brachiaria seed |
| title_fullStr | Methods for extracting plant pathogenic nematodes from Brachiaria seed |
| title_full_unstemmed | Methods for extracting plant pathogenic nematodes from Brachiaria seed |
| title_short | Methods for extracting plant pathogenic nematodes from Brachiaria seed |
| title_sort | methods for extracting plant pathogenic nematodes from brachiaria seed |
| topic | Pests of plants Plant diseases |
| url | https://stud.epsilon.slu.se/8453/ https://stud.epsilon.slu.se/8453/ |