Areawide management of Mexican corn rootworm (Coleoptera:Chrysomelidae) through adult suppression and crop rotation /
Components for Mexican corn rootworm, Diabrotica virgfera zeae Krysan and Smith, areawide management were assessed in Bell County, TX, during l 995, 1996, and 1997. Foliar insecticide applied in a 1,366 ha area to corn, Zea mays L., where corn rootworn adult abundance exceeded treatment thresholds,...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1999.
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| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=730298171&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | Components for Mexican corn rootworm, Diabrotica virgfera zeae Krysan and Smith, areawide management were assessed in Bell County, TX, during l 995, 1996, and 1997. Foliar insecticide applied in a 1,366 ha area to corn, Zea mays L., where corn rootworn adult abundance exceeded treatment thresholds, reduced abundance of adults by 99.1% compared with a non-treated area. In the season following foliar insecticide application, numbers of adults that emerged from corn were reduced by 93.5% in the treated area compared with a non-treated area. Soil insecticide reduced numbers of adults that emerged by 52.3%. Foliar and soil insecticide reduced corn root damage caused by larvae by 2 and l-fold, respectively, compared with non-treated corn. Corn yield was not affected significantly by foliar insecticide, but was 7.8% greater in corn treated with soil insecticide than in that not treated with soil insecticide. Factors where investigated that potentially contributed to failure of crop rotations using sorghums, Sorghum bicolor (L.) Moench, to prevent damage by Mexican corn rootworm to corn. Prolonged diapause of eggs was not observed. Emergence of adults from sorghum was 3.0-11 .2% of that from corn. Oviposition by adults in sorghum was similar to oviposition in corn, suggesting movement of adults for oviposition from corn to sorghum. Oviposition in cotton, Gossypiunl hirsutum L., soybean, Glycine max (L.) Merrill, and Texas panicle, Panicum texanum Buckley, was 23.9, 17.7, and 7.4% of that in com. Four methods for monitoring Mexican corn rootworm were evaluated to determine if a single method could be used to assess adult abundance and emergence patterns for justification and timing of foliar insecticide applications. Standard methods for assessing adult abundance and emergence patterns were plant inspections and emergence traps, respectively. Numbers of adults captured in baited non-sticky traps and sticky 21 for the traps were compared to those obtained by using standard methods. The r[] values for the relationships evaluated revealed the strongest relationship between numbers of adults found by inspecting plants and in emergence traps. Coefficients of variation demonstrated that inspecting plants was more precise than other methods. |
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| Item Description: | Vita. "Major Subject: Entomology". |
| Physical Description: | xiii, 104 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilm Inc. |
| Bibliography: | Includes bibliographical references (leaves 88-103). |