Submitted to: Weather and Climate Extremes
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/1/2015
Publication Date: 8/15/2015
Citation: Hatfield, J.L., Prueger, J.H. 2015. Temperature extremes: Effect on plant growth and development. Weather and Climate Extremes. 10:4-10.
Interpretive Summary: Temperature extremes are expected to occur more often during the summer in which temperatures could easily exceed the upper limits for plant growth and development. Exposure of plants to high temperatures has been observed to increase the rate of development showing that the plant grows more quickly and will mature more quickly. The pollination phase is extremely sensitive to high temperatures and decreases the ability of the plant to set fruit or grain, and continued exposure to high temperatures decreases the length of the grain-filing period. There have been several inferences to the impact of high temperature using simulation models; however, there have been few experiments which have directly measured this impact. We conducted a review of the current literature across different plant species to determine the potential response to high temperature and then measured the response to expected temperature extremes on corn growth and yield in a controlled environment system. Exposure to high temperature events during the growing season affected the grain yield more than the leaf area or biomass of the plant. Exposure to high temperatures throughout the whole growing season increased the rate of plant development but didn’t change the number of leaves the plant produced or the leaf area. The largest effect was on the duration of period where the corn plant was producing grain which led to a large decrease in productivity. Understanding the impacts of temperature on plant growth will help develop strategies to cope with high temperature events. This information will be of value to plant breeders, geneticists, agronomists, and climate scientists to develop strategies to cope with a changing environment.
Technical Abstract: Temperature is a primary factor affecting the rate of plant development. Warmer temperatures expected with climate change and the potential for more extreme temperature events will further impact plant productivity. Pollination is one of the most sensitive phenological stages to temperature extremes across all species, and during this developmental stage temperature extremes would greatly affect production. Few adaptation strategies are available to cope with temperature extremes at this developmental stage other than to select for plants which shed pollen during the cooler periods of the day or are indeterminate so flowering occurs over a longer period of the growing season. In controlled environment studies, warm temperatures increased the rate of phenological development; however, there was no effect on leaf area or vegetative biomass compared to normal temperatures. The major impact of warmer temperatures was during the reproductive stage of development and in all cases grain yield in maize was significantly reduced by as much as 80-90 percent from a normal temperature regime. This effect was further increased by water deficits and excess soil water, demonstrating that the interaction of temperature and water needs to be quantified in order to develop more effective adaptation strategies to offset the impacts of greater temperature extreme events associated with a changing climate.