Open AccessThe influence of fertilizer level and spore density on arbuscular mycorrhizal colonization of transgenic Bt 11 maize ( Zea mays ) in experimental microcosms
Author(s) -
Cheeke Tanya E.,
Pace Brian A.,
Rosenstiel Todd N.,
Cruzan Mitchell B.
Publication year - 2011
Publication title -
fems microbiology ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.377
H-Index - 155
eISSN - 1574-6941
pISSN - 0168-6496
DOI - 10.1111/j.1574-6941.2010.01013.x
Subject(s) - biology , colonization , bacillus thuringiensis , spore , fertilizer , agronomy , microcosm , inoculation , glomus , crop , genetically modified maize , poaceae , cultivar , genetically modified crops , horticulture , botany , transgene , bacteria , ecology , gene , biochemistry , genetics
Crop plants genetically modified for the expression of Bacillus thuringiensis ( Bt ) insecticidal toxins have broad appeal for reducing insect damage in agricultural systems, yet questions remain about the impact of Bt plants on symbiotic soil organisms. Here, arbuscular mycorrhizal fungal (AMF) colonization of transgenic maize isoline Bt 11 (expressing Cry1Ab) and its non‐ Bt parental line (Providence) was evaluated under different fertilizer level and spore density scenarios. In a three‐way factorial design, Bt 11 and non‐ Bt maize were inoculated with 0, 40, or 80 spores of Glomus mosseae and treated weekly with ‘No’ (0 g L −1 ), ‘Low’ (0.23 g L −1 ), or ‘High’ (1.87 g L −1 ) levels of a complete fertilizer and grown for 60 days in a greenhouse. While no difference in AMF colonization was detected between the Bt 11 and Providence maize cultivars in the lower spore/higher fertilizer treatments, microcosm experiments demonstrated a significant reduction in AMF colonization in Bt 11 maize roots in the 80 spore treatments when fertilizer was limited. These results confirm previous work indicating an altered relationship between this Bt 11 maize isoline and AMF and demonstrate that the magnitude of this response is strongly dependent on both nutrient supply and AMF spore inoculation level.