+ Site Statistics
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on LinkedInFollow on LinkedIn

+ Translate

Elevated root-zone CO protects lettuce plants from midday depression of photosynthesis

Elevated root-zone CO protects lettuce plants from midday depression of photosynthesis

Environmental and experimental botany 61(1): 94-101

Effects of elevated root-zone (RZ) CO on photosynthesis and productivity of lettuce plants grown in a greenhouse were investigated over a period of 2 weeks. Four levels of RZ CO were imposed on lettuce roots 3 weeks after transplanting by supplying air with CO concentrations in the range between ambient (360 ppm) and 50,000 ppm. Elevated RZ CO produced no significant increase of photosynthetic CO assimilation (A) and stomatal conductance (g(s)) during the first 2-3 h following sun rise. Compared to control plants grown at ambient RZ CO, elevated RZ CO treatment resulted in significant increases and decreases in A and g(s), respectively, during the late morning. By midday, however, there was a substantial decline in A, which could attribute to both increase in stomatal limitation of A and dynamic photoinhibition of PSII as g(s) and Fv/F(m) ratios were lowest in all plants during midday between 13:00 and 14:00 h. Midday depressions of A and Fv/F(m) ratios were alleviated in elevated RZ CO treated plants. However, elevated RZ CO significantly decreased g(s) accompanying higher midday RWC. During the onset of different RZ CO treatments, leaf expansions were measured to examine the response of leaf growth to elevated RZ CO over a period of 5 days. Productivities of shoot and root were also determined by the end of 2 weeks treated with different RZ CO. The results indicate that elevated RZ CO enhanced leaf area, shoot and root productivities. It was predicted that increasing RZ CO could alleviate midday depression of photosynthesis and hence increase the productivity of lettuce plants.

(PDF same-day service: $19.90)

Accession: 015691550

Download citation: RISBibTeXText

DOI: 10.1016/j.envexpbot.2007.04.001

Related references

Elevated root-zone CO2 protects lettuce plants from midday depression of photosynthesis. Environmental and Experimental Botany 61(1): 94-101, 2007

Effect of root-zone (RZ) CO2 on productivity and photosynthesis in aeroponically grown lettuce plants. Acta Horticulturae (648): 39-45, 2004

Study of the cause of midday depression in photosynthesis in wheat. II. The relationship of physiological factors to midday depression. Acta Agronomica Sinica 13(4): 329-335, 1987

Effects of elevated root zone CO2 and air temperature on photosynthetic gas exchange, nitrate uptake, and total reduced nitrogen content in aeroponically grown lettuce plants. Journal of Experimental Botany 61(14): 3959-3969, 2010

Limitations to photosynthesis of lettuce grown under tropical conditions: alleviation by root-zone cooling. Journal of Experimental Botany 52(359): 1323-1330, 2001

A consideration on the midday depression of photosynthesis.. J. agric. Met, Tokyo 11-14. bibl. 18, 1963

Short- and long-term effects of a change in the spatial distribution of nitrate in the root zone on N uptake, growth and root development of young lettuce plants. Plant, Cell and Environment 14(1): 21-33, 1991

An analysis of the causes of midday depression of photosynthesis in soyabean leaves. Acta Agronomica Sinica 20(3): 357-362, 1994

A study on the causes of midday depression of photosynthesis in wheat and measures for its relief. Acta Ecologica Sinica 7(4): 314-321, 1987

Effect of accumulation of photosynthates on the midday depression of photosynthesis in soyabean. Acta Agriculturae Boreali Sinica 7(4): 9-13, 1992

On midday depression of photosynthesis of wheat leaf under field conditions. Acta Phytophysiologia Sinica 10(3): 269-276, 1984

Midday depression of photosynthesis and effects of mist spray in citrus. Annals of Applied Biology 154(1): 143-155, 2009

Nonstomatic limitations in midday depression of photosynthesis in winter wheat leaves. Yingyong Shengtai Xuebao 12(5): 799-800, October, 2001

Factors determining the midday depression of photosynthesis in trees under monsoon climate. Trees (Berlin) 12(8): 472-481, 1998