Hostname: page-component-cd9895bd7-gvvz8 Total loading time: 0 Render date: 2024-12-18T13:43:42.269Z Has data issue: false hasContentIssue false
  • English
  • Français

Photosynthesis and Stomatal-Conductance Responses of Johnsongrass (Sorghum halepense) to Water Stress

Published online by Cambridge University Press:  12 June 2017

Bryan L. Stuart ,
Daniel R. Krieg  and
John R. Abernathy
Bryan L. Stuart
Affiliation:
Dep. Plant and Soil Sci., Texas Tech. Univ., TX 79401
Daniel R. Krieg
Affiliation:
Dep. Plant and Soil Sci., Texas Tech. Univ., TX 79401
John R. Abernathy
Affiliation:
Weed Science, Texas Agric. Exp. Stn., Lubbock, TX 79401
Get access Rights & Permissions [Opens in a new window]

Abstract

The influence of water stress on johnsongrass [Sorghum halepense (L.) Pers. ♯ SORHA] physiology was evaluated in a semiarid environment. Stomatal conductance of johnsongrass responded to more negative leaf water potential and increasing leaf temperature. The sensitivity of the leaf temperature effect was dependent on the soil water content. At low soil water content, conductance was limited by low water potential, and increasing leaf temperature had little effect. Conductance of CO2 was related to net photosynthesis in a curvilinear manner, with conductance levels greater than 0.3 mol·m-2· s-1 being in excess of that necessary for maximum photosynthesis. At both high conductance levels and low levels associated with increased water stress, intercellular CO2 concentration increased, indicating nonstomatal limitations to photosynthesis. Decreased osmotic potential provided the highest correlation with the linear decline of photosynthetic rate as stress intensified. The expression of osmotic adjustment in johnsongrass is reported during grain filling. Plants in the milkdough stage of grain filling had approximately 0.3 MPa lower osmotic potential at any relative water content than those at anthesis.

Keywords

Water relationsosmotic adjustmentdesiccation resistanceSORHA
Type
Physiology, Chemistry, and Biochemistry
Information
Weed Science , Volume 33 , Issue 5 , September 1985 , pp. 635 - 639
Copyright
Copyright © 1985 by the Weed Science Society of America 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Literature Cited

1. Ackerson, R. C., Krieg, D. R., Haring, C L., and Chang, N. 1977. Effects of plant water status on stomatal activity, photosynthesis, and nitrate reductase activity of field grown cotton. Crop Sci. 17:81–84.CrossRefGoogle Scholar
2. Ackerson, R. C., Krieg, D. R., and Sung, F.J.M. 1980. Leaf conductance and osmoregulation of field-grown sorghum genotypes. Crop Sci. 20:10–14.Google Scholar
3. Berkowitz, G. A. and Gibbs, M. 1983. Reduced osmotic potential inhibition of photosynthesis. Site-specific effects of osmotically induced stromal acidification. Plant Physiol. 72:1100–1109.Google Scholar
4. Boyer, J. S. 1976. Photosynthesis at low water potentials. Philos. Trans. R. Soc. London Ser. B. 273:501–512.Google Scholar
5. Farquhar, G. D. and Sharkey, T. D. 1982. Stomatal conductance and photosynthesis. Annu. Rev. Plant Physiol. 33:317–345.Google Scholar
6. Farquhar, G. D., Shulze, E. D., and Kuppers, M. 1980. Responses to humidity by stomata of Nicotiana glauca L. and Corylus avelana L. are consistent with the optimization of carbon dioxide uptake with respect to water loss. Aust. J. Plant Physiol. 7:315–327.Google Scholar
7. Gates, D. M. 1980. Biophysical Ecology. Springer-Verlag.Google Scholar
8. Jones, M. M. and Turner, N. C. 1978. Osmotic adjustment in leaves of sorghum in response to water deficits. Plant Physiol. 61:122–126.CrossRefGoogle ScholarPubMed
9. McWhorter, C. G. 1971. Anatomy of johnsongrass. Weed Sci. 19:385–393.CrossRefGoogle Scholar
10. McWhorter, C. G. 1971. Growth and development of johnsongrass ecotypes. Weed Sci. 19:141–147.CrossRefGoogle Scholar
11. McWhorter, C. G. and Jordan, T. N. 1976. Comparative morphological development of six johnsongrass ecotypes. Weed Sci. 24:270–275.Google Scholar
12. Radin, J. W. and Ackerson, R. C. 1981. Water relations of cotton plants under nitrogen deficiency. III. Stomatal conductance, photosynthesis, and abscisic acid accumulation during drought. Plant Physiol. 67:115–119.CrossRefGoogle ScholarPubMed
13. Ray, A. A. 1982. SAS User's Guide: Statistics. SAS Institute, Inc., Cary, NC.Google Scholar
14. Stuart, B. L., Harrison, S. K., Abernathy, J. R., Krieg, D. R., and Wendt, C. W. 1984. The response of cotton (Gossypium hirsutum) water relations to smooth pigweed (Amaranthus hybridus) competition. Weed Sci. 32:126–132.Google Scholar
15. Wong, S. C., Cowan, I. R., and Farquhar, G. D. 1979. Stomatal conductance correlates with photosynthetic capacity. Nature (London) 282:424–426.CrossRefGoogle Scholar