Field Performance of Bt Eggplants (Solanum melongena L.) in the Philippines: Cry1Ac Expression and Control of the Eggplant Fruit and Shoot Borer (Leucinodes orbonalis Guenée).
Plants expressing Cry proteins from the bacterium, Bacillus thuringiensis (Bt), have become a major tactic for controlling insect pests in maize and cotton globally. However, there are few Bt vegetable crops. Eggplant (Solanum melongena) is a popular vegetable grown throughout Asia that is heavily treated with insecticides to control the eggplant fruit and shoot borer, Leucinodes orbonalis (EFSB). Herein we provide the first publicly available data on field performance in Asia of eggplant engineered to produce the Cry1Ac protein. Replicated field trials with five Bt eggplant open-pollinated (OP) lines from transformation event EE-1 and their non-Bt comparators were conducted over three cropping seasons in the Philippines from 2010-2012. Field trials documented levels of Cry1Ac protein expressed in plants and evaluated their efficacy against the primary target pest, EFSB. Cry1Ac concentrations ranged from 0.75-24.7 ppm dry weight with the highest in the terminal leaves (or shoots) and the lowest in the roots. Cry1Ac levels significantly increased from the vegetative to the reproductive stage. Bt eggplant lines demonstrated excellent control of EFSB. Pairwise analysis of means detected highly significant differences between Bt eggplant lines and their non-Bt comparators for all field efficacy parameters tested. Bt eggplant lines demonstrated high levels of control of EFSB shoot damage (98.6-100%) and fruit damage (98.1-99.7%) and reduced EFSB larval infestation (95.8-99.3%) under the most severe pest pressure during trial 2. Moths that emerged from larvae collected from Bt plants in the field and reared in their Bt eggplant hosts did not produce viable eggs or offspring. These results demonstrate that Bt eggplant lines containing Cry1Ac event EE-1 provide outstanding control of EFSB and can dramatically reduce the need for conventional insecticides.
Institute of Plant Breeding/CSC, College of Agriculture, University of the Philippines Los Baños, College, Laguna, 4031, Philippines.
Desiree M
DM
Hautea
Institute of Plant Breeding/CSC, College of Agriculture, University of the Philippines Los Baños, College, Laguna, 4031, Philippines.
Lourdes D
LD
Taylo
Institute of Plant Breeding/CSC, College of Agriculture, University of the Philippines Los Baños, College, Laguna, 4031, Philippines.
Anna Pauleen L
AP
Masanga
Institute of Plant Breeding/CSC, College of Agriculture, University of the Philippines Los Baños, College, Laguna, 4031, Philippines.
Maria Luz J
ML
Sison
Institute of Plant Breeding/CSC, College of Agriculture, University of the Philippines Los Baños, College, Laguna, 4031, Philippines.
Josefina O
JO
Narciso
Institute of Plant Breeding/CSC, College of Agriculture, University of the Philippines Los Baños, College, Laguna, 4031, Philippines.
Reynaldo B
RB
Quilloy
International Service for the Acquisition of Agri-Biotech Applications, Los Baños, Laguna, 4030, Philippines.
Randy A
RA
Hautea
International Programs, Cornell University, Ithaca, New York, 14853, United States of America.
Frank A
FA
Shotkoski
Department of Entomology, Cornell/NYSAES, Geneva, New York, 14456, United States of America.
Anthony M
AM
Shelton
D000818:Animals; D001208:Asia; D001413:Bacillus thuringiensis / Q000235:genetics; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics*; D018556:Crops, Agricultural / Q000235:genetics / Q000254:growth & development; D004731:Endotoxins / Q000096:biosynthesis / Q000235:genetics*; D005638:Fruit / Q000235:genetics* / Q000254:growth & development / Q000382:microbiology / Q000469:parasitology; D018506:Gene Expression Regulation, Plant; D006460:Hemolysin Proteins / Q000096:biosynthesis / Q000235:genetics*; D007814:Larva / Q000472:pathogenicity; D009036:Moths / Q000472:pathogenicity; D010572:Pest Control, Biological; D010679:Philippines; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development / Q000382:microbiology; D010940:Plant Proteins / Q000096:biosynthesis / Q000235:genetics; D018520:Plant Shoots / Q000235:genetics / Q000254:growth & development / Q000382:microbiology; D032323:Solanum melongena / Q000235:genetics* / Q000254:growth & development / Q000382:microbiology / Q000469:parasitology
D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; D010940:Plant Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis