Earthworms
Fifteen plastic pots (18 cm dia., 21 cm deep; ®ve each for Bt corn, non-Bt corn, and with no plants) were each ®lled with ca. 4.5 kg of soil, and 20 medium-size earthworms (Lumbricus terrestris), with well developed clitellum, purchased from Carolina Biological Supply Company (Burlington, North Carolina), were placed in each pot and kept overnight in the dark at 24 2VC when the worms entered the soil. Before the earthworms were introduced, the colony-forming units (CFU) of culturable bacteria and fungi, as well as the numbers of protozoa and nematodes, in the soil were determined. Seeds of Bt corn (NK4640Bt) and of isogenic non-Bt corn were planted (three seeds per pot), and after 40 days of growth in a plant-growth room (26 2VC, 12 h light±dark cycle; soil water content main- tained at ca. ®eld capacity, and no water stress was apparent in the plants), the plants were gently removed and rhizo- sphere soil was collected by gently shaking the roots to dislodge adhering small clumps of soil. To determine the effects of biomass from Bt and non-Bt corn on earthworms and the other organisms, 500 g of soil amended with 1% (w wP1) of ground, air-dried biomass of Bt corn (NK4640Bt) or isogenic non-Bt corn (leaves, stems, and roots) was placed into each of ®ve jars (10 cm dia., 16 cm deep), and ®ve medium-size earthworms were added to each jar. Two control jars received no biomass. All jars were kept in the plant-growth room for 45 days with the soil maintained at ca. ®eld capacity. Casts produced by the earthworms were collected from all pots and jars. After incubation, the earth- worms in the pots and jars were counted and their weight determined. Three representative worms from each pot and two from each jar were dissected, and soil from the guts was analyzed for the presence of Cry1Ab protein by immunolo- gical and larvicidal assays.
To determine the time required to clear the toxin from the guts of earthworms, worms from pots of Bt corn and from jars amended with biomass of Bt corn were gently removed and transferred to pots containing fresh soil that had not been exposed to Bt toxin. After 1, 2, and 3 days, represen- tative earthworms were dissected, and the soil in their guts was analyzed for the presence of the toxin.
ไส้เดือนFifteen plastic pots (18 cm dia., 21 cm deep; ®ve each for Bt corn, non-Bt corn, and with no plants) were each ®lled with ca. 4.5 kg of soil, and 20 medium-size earthworms (Lumbricus terrestris), with well developed clitellum, purchased from Carolina Biological Supply Company (Burlington, North Carolina), were placed in each pot and kept overnight in the dark at 24 2VC when the worms entered the soil. Before the earthworms were introduced, the colony-forming units (CFU) of culturable bacteria and fungi, as well as the numbers of protozoa and nematodes, in the soil were determined. Seeds of Bt corn (NK4640Bt) and of isogenic non-Bt corn were planted (three seeds per pot), and after 40 days of growth in a plant-growth room (26 2VC, 12 h light±dark cycle; soil water content main- tained at ca. ®eld capacity, and no water stress was apparent in the plants), the plants were gently removed and rhizo- sphere soil was collected by gently shaking the roots to dislodge adhering small clumps of soil. To determine the effects of biomass from Bt and non-Bt corn on earthworms and the other organisms, 500 g of soil amended with 1% (w wP1) of ground, air-dried biomass of Bt corn (NK4640Bt) or isogenic non-Bt corn (leaves, stems, and roots) was placed into each of ®ve jars (10 cm dia., 16 cm deep), and ®ve medium-size earthworms were added to each jar. Two control jars received no biomass. All jars were kept in the plant-growth room for 45 days with the soil maintained at ca. ®eld capacity. Casts produced by the earthworms were collected from all pots and jars. After incubation, the earth- worms in the pots and jars were counted and their weight determined. Three representative worms from each pot and two from each jar were dissected, and soil from the guts was analyzed for the presence of Cry1Ab protein by immunolo- gical and larvicidal assays.การกำหนดระยะเวลาการล้างสารพิษจากเครื่องในของไส้เดือน หนอน จากหม้อของข้าวโพดบีที และไหที่แก้ไขกับชีวมวลของ Bt ข้าวโพดค่อย ๆ ถูกลบออก และโอนย้ายไปที่กระถางที่ประกอบด้วยดินสดที่ไม่ได้รับการสัมผัสกับสารพิษ Bt หลังจาก 1, 2 และ 3 วัน วอชิงตันดีซี tative ไส้เดือนถูก dissected และถูกวิเคราะห์ดินในความกล้าของพวกเขาสำหรับการปรากฏตัวของสารพิษ
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