Author
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Hatfield, Jerry |
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Submitted to: Agricultural and Environmental Letters
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 1/15/2016 Publication Date: 2/26/2016 Citation: Hatfield, J.L. 2016. Increased temperatures have dramatic effects on growth and grain yield on three maize hybrids. Agricultural and Environmental Letters. 1:15006. Interpretive Summary: Climate change and its potential impact on agriculture is a topic of concern because of the need to provide for effective adaptation strategies; however, there is little known about the direct impacts of temperature increase on plant growth and yield. The current estimates of the projected impacts are extrapolations from models or extension of current findings. A study conducted in a controlled environment system evaluated the effect of temperature on different corn hybrids with a projected temperature expected to occur by the end of the 21st century. The increased temperatures hastened the rate of plant growth but did not affect the size of the plant. The largest effect was on the grain production, which showed a very large decrease due to the increase in nighttime temperatures during the latter stages of growth. Increasing temperatures will have a significant impact on grain production in the future. This information will be of value to plant breeders, agricultural climatologist, policy makers, and climate scientists. Technical Abstract: Rising temperatures under climate change are projected to have negative impacts on crop growth and production. These conclusions have been reached based on the analysis of historical data with no direct observations of projected temperatures for the end of the 21st century. A study conducted comparing normal seasonal temperatures (1980-2010) for Ames to Normal + 4°C environment with the same water vapor deficit to isolate the effects to only temperature evaluated the impacts of temperature on maize development and production. Rate of phenological development increased at higher temperatures; however, the relationship of leaf collar and leaf tip appearance to growing degree days was the same between temperature regimes. There was no effect on total leaf area or vegetative dry matter production but grain yields decreased from 84 to 100% because of exposure to high nighttime temperatures. Projected increases in temperature will negatively impact grain production and threaten food security. |
