Abstract Detail

Physiological Section

Giri, Anju [1], Mishra, Sasmita [1], Heckathorn, Scott [1].

Effect of abrupt heat stress on nutrient uptake by plant roots.

With impending climate change, plants in the future are likely to experience more frequent, severe, and longer-duration heat-stress events, which will likely have negative effects on plant function. The impact of abrupt heat stress on plant nutrient uptake is unclear, since most past studies have examined uptake under highly-artificial conditions (e.g., detached roots), which likely yielded artifactual results. Hence, we are investigating effects of high temperatures, both chronic and abrupt increases, on nutrient uptake by roots, using tomato as a model system. In the current study, we grew plants at 25/20^oC (day/night) (= control conditions) and then transferred some plants to 35/30^oC (moderate heat) or 42/37^oC (severe heat) for 6 days, after which, plants were moved back to control conditions for 7 days to monitor recovery. Samples were harvested after 1 and 6 days of heat treatment, and after 7 days of recovery (day 13), and then the concentration of major nutrient transport proteins was determined using protein specific antibodies and ELISA. Photosynthesis was reduced by severe heat (but increased by moderate heat), compared to controls, and recovered within 7 days of a return to control temperatures. Roots were damaged by severe, but not moderate, heat, as indicated by measurements of respiration and electrolyte leakage, and both moderate and, especially, severe heat reduced root mass. Effects of high temperatures on levels of nutrient metabolism proteins or nutrient uptake were variable among proteins and nutrients. Together, our results indicate that abrupt heat events can damage roots and decrease root nutrient uptake, by decreasing root metabolic rate, levels of nutrient transporter proteins, and/or root mass.

Broader Impacts:

1 - Departmnet of Environmental Sciences, MS#604, 2801 West Bancroft St, Toledo, OH, 43606, USA

Keywords:
heat stress
nutrient uptake
nutrient transporter protein.

Presentation Type: Oral Paper:Papers for Sections
Session: 17
Location: Newberry/Riverside Hilton
Date: Tuesday, July 30th, 2013
Time: 9:00 AM
Number: 17003
Abstract ID:418
Candidate for Awards:Physiological Section Physiological Section Li-COR Prize