語系:
繁體中文
English
說明(常見問題)
回圖書館首頁
手機版館藏查詢
登入
回首頁
切換:
標籤
|
MARC模式
|
ISBD
An evaluation of the nontarget effec...
~
Cheeke, Tanya Elizabeth Amy.
FindBook
Google Book
Amazon
博客來
An evaluation of the nontarget effects of transgenic Bacillus thuringiensis maize on arbuscular mycorrhizal fungi in the soil ecosystem.
紀錄類型:
書目-語言資料,印刷品 : Monograph/item
正題名/作者:
An evaluation of the nontarget effects of transgenic Bacillus thuringiensis maize on arbuscular mycorrhizal fungi in the soil ecosystem./
作者:
Cheeke, Tanya Elizabeth Amy.
面頁冊數:
285 p.
附註:
Source: Dissertation Abstracts International, Volume: 75-01(E), Section: B.
Contained By:
Dissertation Abstracts International75-01B(E).
標題:
Biology, General. -
電子資源:
http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3593573
ISBN:
9781303367762
An evaluation of the nontarget effects of transgenic Bacillus thuringiensis maize on arbuscular mycorrhizal fungi in the soil ecosystem.
Cheeke, Tanya Elizabeth Amy.
An evaluation of the nontarget effects of transgenic Bacillus thuringiensis maize on arbuscular mycorrhizal fungi in the soil ecosystem.
- 285 p.
Source: Dissertation Abstracts International, Volume: 75-01(E), Section: B.
Thesis (Ph.D.)--Portland State University, 2013.
My dissertation research examined the effect of the cultivation of insect-resistant Bacillus thuringiensis (Bt) maize on the soil environment with a goal of understanding how to obtain a balance between technological advancement and maintenance of a healthy soil ecosystem. Although Bt plants may help to reduce pesticide use, conferring benefits to farm workers and the environment, there are still unresolved questions about how the cultivation of Bt plants affects soil organisms. For this dissertation project, I used 14 different genotypes of Bt maize and non-Bt maize (Zea mays) to investigate the effects of transgenic Bt plants on the colonization ability, abundance, and diversity of symbiotic arbuscular mycorrhizal fungi (AMF) in the soil ecosystem over time. My greenhouse studies demonstrated that Bt maize plants exhibited reduced AMF colonization across multiple Bt genotypes and that effects were most pronounced when fertilizer levels were limited and spore density was high. In addition, I found that although differences in AMF colonization between Bt and non-Bt maize were difficult to detect in the field, spore density was reduced in Bt field plots after just one growing season. When I tested the effect of plot history on AMF and plant growth, I found that Bt and non-Bt maize plants had higher leaf chlorophyll content when grown in plots previously cultivated with the same maize line as the previous year, indicative of a positive feedback effect. I also examined potential mechanisms contributing to the reduced AMF colonization observed in Bt maize in greenhouse studies and determined that follow-up experiments should continue to investigate differences in root apoplastic invertase activity and root permeability in Bt and non-Bt maize. Future investigations would also benefit from examining potential differences in root exudate profiles and volatile organic compounds between Bt and non-Bt cultivars. Taken together, my dissertation results suggest that, while difficult to detect in the field, reductions in AMF colonization in Bt maize roots may be ecologically significant as they could lead to a decrease in the abundance of AMF propagules in the soil over time, potentially impacting soil structure and function in areas where Bt crop cultivation is high.
ISBN: 9781303367762Subjects--Topical Terms:
1018625
Biology, General.
An evaluation of the nontarget effects of transgenic Bacillus thuringiensis maize on arbuscular mycorrhizal fungi in the soil ecosystem.
LDR
:03275nam a2200301 4500
001
1961001
005
20140701144900.5
008
150210s2013 ||||||||||||||||| ||eng d
020
$a
9781303367762
035
$a
(MiAaPQ)AAI3593573
035
$a
AAI3593573
040
$a
MiAaPQ
$c
MiAaPQ
100
1
$a
Cheeke, Tanya Elizabeth Amy.
$3
2096802
245
1 3
$a
An evaluation of the nontarget effects of transgenic Bacillus thuringiensis maize on arbuscular mycorrhizal fungi in the soil ecosystem.
300
$a
285 p.
500
$a
Source: Dissertation Abstracts International, Volume: 75-01(E), Section: B.
500
$a
Adviser: Mitchell B. Cruzan.
502
$a
Thesis (Ph.D.)--Portland State University, 2013.
520
$a
My dissertation research examined the effect of the cultivation of insect-resistant Bacillus thuringiensis (Bt) maize on the soil environment with a goal of understanding how to obtain a balance between technological advancement and maintenance of a healthy soil ecosystem. Although Bt plants may help to reduce pesticide use, conferring benefits to farm workers and the environment, there are still unresolved questions about how the cultivation of Bt plants affects soil organisms. For this dissertation project, I used 14 different genotypes of Bt maize and non-Bt maize (Zea mays) to investigate the effects of transgenic Bt plants on the colonization ability, abundance, and diversity of symbiotic arbuscular mycorrhizal fungi (AMF) in the soil ecosystem over time. My greenhouse studies demonstrated that Bt maize plants exhibited reduced AMF colonization across multiple Bt genotypes and that effects were most pronounced when fertilizer levels were limited and spore density was high. In addition, I found that although differences in AMF colonization between Bt and non-Bt maize were difficult to detect in the field, spore density was reduced in Bt field plots after just one growing season. When I tested the effect of plot history on AMF and plant growth, I found that Bt and non-Bt maize plants had higher leaf chlorophyll content when grown in plots previously cultivated with the same maize line as the previous year, indicative of a positive feedback effect. I also examined potential mechanisms contributing to the reduced AMF colonization observed in Bt maize in greenhouse studies and determined that follow-up experiments should continue to investigate differences in root apoplastic invertase activity and root permeability in Bt and non-Bt maize. Future investigations would also benefit from examining potential differences in root exudate profiles and volatile organic compounds between Bt and non-Bt cultivars. Taken together, my dissertation results suggest that, while difficult to detect in the field, reductions in AMF colonization in Bt maize roots may be ecologically significant as they could lead to a decrease in the abundance of AMF propagules in the soil over time, potentially impacting soil structure and function in areas where Bt crop cultivation is high.
590
$a
School code: 0180.
650
4
$a
Biology, General.
$3
1018625
650
4
$a
Biology, Ecology.
$3
1017726
650
4
$a
Biology, Botany.
$3
1017825
650
4
$a
Biology, Microbiology.
$3
1017734
690
$a
0306
690
$a
0329
690
$a
0309
690
$a
0410
710
2
$a
Portland State University.
$b
Biology.
$3
2096803
773
0
$t
Dissertation Abstracts International
$g
75-01B(E).
790
$a
0180
791
$a
Ph.D.
792
$a
2013
793
$a
English
856
4 0
$u
http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3593573
筆 0 讀者評論
館藏地:
全部
電子資源
出版年:
卷號:
館藏
1 筆 • 頁數 1 •
1
條碼號
典藏地名稱
館藏流通類別
資料類型
索書號
使用類型
借閱狀態
預約狀態
備註欄
附件
W9255829
電子資源
11.線上閱覽_V
電子書
EB
一般使用(Normal)
在架
0
1 筆 • 頁數 1 •
1
多媒體
評論
新增評論
分享你的心得
Export
取書館
處理中
...
變更密碼
登入