JXB Advance Access originally published online on January 12, 2004
Journal of Experimental Botany, Vol. 55, No. 396, pp. 497-505, February 1, 2004
© 2004 Oxford University Press
Plants and the Environment |
Response to water deficit and high temperature of transgenic peas (Pisum sativum L.) containing a seed-specific 
-amylase inhibitor and the subsequent effects on pea weevil (Bruchus pisorum L.) survival
Received 29 January 2003; Accepted 13 October 2003
1 Department of Environmental Biology, Curtin University of Technology PO Box U1987, Perth, WA 6845, Australia
2 Western Australian Department of Agriculture, Locked Bag No.4, Bentley, WA 6983, Australia
3 CSIRO Plant Industry, Private Bag No. 5, Wembley, WA 6913, Australia
4 CSIRO Plant Industry, GPO Box 1600, Canberra, ACT 2601, Australia
* To whom correspondence should be addressed. E-mail: M.Majer{at}curtin.edu.au
The effects of water deficit and high temperature on the production of 
-amylase inhibitor 1 (-AI-1) were studied in transgenic peas (Pisum sativum L.) that were developed to control the seed-feeding pea weevil (Bruchus pisorum L., Coleoptera: Bruchidae). Transgenic and non-transgenic plants were subjected to water-deficit and high-temperature treatments under controlled conditions in the glasshouse and growth cabinet, beginning 1 week after the first pods were formed. In the water-deficit treatments, the peas were either adequately watered (control) or water was withheld after first pod formation. The high-temperature experiments were performed in two growth cabinets, one maintained at 27/22 °C (control) and one at 32/27 °C day/night temperatures, with the vapour pressure deficit maintained at 1.3 kPa. The plants exposure to high temperatures and water deficit produced 27% and 79% fewer seeds, respectively, than the controls. In the transgenic peas the level of -AI-1 as a percentage of total protein was not influenced by water stress, but was reduced on average by 36.3% (the range in two experiments was 11–50%) in the high-temperature treatment. Transgenic and non-transgenic pods of plants grown at 27/22 °C and 32/27 °C were inoculated with pea weevil eggs to evaluate whether the reduction in level of -AI-1 in the transgenic pea seeds affected pea weevil development and survival. At the higher temperatures, 39% of adult pea weevil emerged, compared to 1.2% in the transgenic peas grown at the lower temperatures, indicating that high temperature reduced the protective capacity of the transgenic peas.
Key words: Alpha-amylase inhibitor, Bruchus pisorum, high-temperature stress, Pisum sativum, transgenic peas, water deficit.