Skip to main content
NCBI home page
Plant Physiology logoLink to Plant Physiology
. 1992 Dec;100(4):2052–2058. doi: 10.1104/pp.100.4.2052

Pleiotropy in Triazine-Resistant Brassica napus1

Ontogenetic and Diurnal Influences on Photosynthesis

Jack H Dekker 1, Ronald G Burmester 1
PMCID: PMC1075906  PMID: 16653239

Abstract

Studies were conducted that supported the hypothesis that the mutation to the psbA plastid gene that confers S-triazine resistance (R) in Brassica napus also results in an altered diurnal pattern of photosynthetic carbon assimilation (A) relative to that of the susceptible (S) wild type, and that these patterns change over the ontogeny of a plant. Photosynthetic photon flux density, under closely controlled environmental conditions, was incrementally increased and decreased on either side of the midday maxima of 1150 to 1300 μmol quanta m−2 s−1. In all experiments, A approximately tracked the increasing and decreasing diurnal light levels. Younger (3- to 4-leaf) R plants had greater photosynthetic rates early and late in the diurnal light period, whereas those of S plants were greater during midday as well as during the photoperiod as a whole. These relative photosynthetic characteristics of R and S plants changed in several ways with ontogeny. As the plants aged during the vegetative phase of development, S plants gradually assimilated more carbon in the early, and then in the late, part of the day. At the end of the vegetative phase of development, R plant carbon assimilation was less relative to S plants at most times of the day, and was never greater. This relationship between the two biotypes dramatically changed with the onset of the reproductive phase (8½ to 9½ leaf) of plant development: R plants assimilated more carbon than S plants during all periods of the diurnal light period with the exception of the late part of the day. In addition to these differences in A, R plant stomatal function differed from that in S plants. R plant leaves were always cooler than S plant leaves under the same environmental and diurnal conditions. Correlated with this difference in leaf temperature were equal or greater total conductances to water vapor and intercellular CO2 partial pressures in R compared to S leaves in most instances. These studies indicate a more complex pattern of photosynthetic carbon assimilation than previously observed. The photosynthetic superiority of one biotype relative to the other was a function of the time of day and the age of the plant. These studies also suggest that R plants may have an adaptive advantage over S plants in certain unfavorable ecological niches independent of the presence of S-triazine herbicides, such as cool, low-light environments early and late in the day, as well as late in the plants' development. This advantage could result in R biotypes appearing in populations of a species in greater numbers than plastidic mutation alone could cause.

Full text

PDF
2052

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Arntzen C. J., Ditto C. L., Brewer P. E. Chloroplast membrane alterations in triazine-resistant Amaranthus retroflexus biotypes. Proc Natl Acad Sci U S A. 1979 Jan;76(1):278–282. doi: 10.1073/pnas.76.1.278. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Dekker J. H., Sharkey T. D. Regulation of Photosynthesis in Triazine-Resistant and -Susceptible Brassica napus. Plant Physiol. 1992 Mar;98(3):1069–1073. doi: 10.1104/pp.98.3.1069. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Hennessey T. L., Field C. B. Circadian Rhythms in Photosynthesis : Oscillations in Carbon Assimilation and Stomatal Conductance under Constant Conditions. Plant Physiol. 1991 Jul;96(3):831–836. doi: 10.1104/pp.96.3.831. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Hirschberg J., McIntosh L. Molecular Basis of Herbicide Resistance in Amaranthus hybridus. Science. 1983 Dec 23;222(4630):1346–1349. doi: 10.1126/science.222.4630.1346. [DOI] [PubMed] [Google Scholar]
  5. Holt J. S., Goffner D. P. Altered Leaf Structure and Function in Triazine-Resistant Common Groundsel (Senecio vulgaris). Plant Physiol. 1985 Nov;79(3):699–705. doi: 10.1104/pp.79.3.699. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Holt J. S., Stemler A. J., Radosevich S. R. Differential Light Responses of Photosynthesis by Triazine-resistant and Triazine-susceptible Senecio vulgaris Biotypes. Plant Physiol. 1981 Apr;67(4):744–748. doi: 10.1104/pp.67.4.744. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Hugly S., Kunst L., Browse J., Somerville C. Enhanced thermal tolerance of photosynthesis and altered chloroplast ultrastructure in a mutant of Arabidopsis deficient in lipid desaturation. Plant Physiol. 1989 Jul;90(3):1134–1142. doi: 10.1104/pp.90.3.1134. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Jursinic P. A., Pearcy R. W. Determination of the Rate Limiting Step for Photosynthesis in a Nearly Isonuclear Rapeseed (Brassica napus L.) Biotype Resistant to Atrazine. Plant Physiol. 1988 Dec;88(4):1195–1200. doi: 10.1104/pp.88.4.1195. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Kunst L., Browse J., Somerville C. Altered chloroplast structure and function in a mutant of Arabidopsis deficient in plastid glycerol-3-phosphate acyltransferase activity. Plant Physiol. 1989 Jul;90(3):846–853. doi: 10.1104/pp.90.3.846. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Mattoo A. K., St John J. B., Wergin W. P. Adaptive reorganization of protein and lipid components in chloroplast membranes as associated with herbicide binding. J Cell Biochem. 1984;24(2):163–175. doi: 10.1002/jcb.240240207. [DOI] [PubMed] [Google Scholar]
  11. McCloskey W. B., Holt J. S. Triazine Resistance in Senecio vulgaris Parental and Nearly Isonuclear Backcrossed Biotypes Is Correlated with Reduced Productivity. Plant Physiol. 1990 Apr;92(4):954–962. doi: 10.1104/pp.92.4.954. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Ort D. R., Ahrens W. H., Martin B., Stoller E. W. Comparison of Photosynthetic Performance in Triazine-Resistant and Susceptible Biotypes of Amaranthus hybridus. Plant Physiol. 1983 Aug;72(4):925–930. doi: 10.1104/pp.72.4.925. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Pillai P., John J. B. Lipid composition of chloroplast membranes from weed biotypes differentially sensitive to triazine herbicides. Plant Physiol. 1981 Sep;68(3):585–587. doi: 10.1104/pp.68.3.585. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Schönfeld M., Yaacoby T., Michael O., Rubin B. Triazine Resistance without Reduced Vigor in Phalaris paradoxa. Plant Physiol. 1987 Feb;83(2):329–333. doi: 10.1104/pp.83.2.329. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Stowe A. E., Holt J. S. Comparison of Triazine-Resistant and -Susceptible Biotypes of Senecio vulgaris and Their F(1) Hybrids. Plant Physiol. 1988 May;87(1):183–189. doi: 10.1104/pp.87.1.183. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Vaughn K. C. Characterization of Triazine-Resistant and -Susceptible Isolines of Canola (Brassica napus L.). Plant Physiol. 1986 Nov;82(3):859–863. doi: 10.1104/pp.82.3.859. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Plant Physiology are provided here courtesy of Oxford University Press

RESOURCES