Studies on the germination and dormancy of Polygonum persicaria L

Mensah, Stephen Ikechukwu (1984) Studies on the germination and dormancy of Polygonum persicaria L. PhD thesis, University of Glasgow.

Abstract

Studies on the germination and the nature of dormancy of achenes of Polygonum persicaria were carried out. The release from dormancy was investigated by physical and chemical treatments, environmental factors (temperature and light) and the application of plant hormones. The imposition of dormancy on non-dormant achenes was examined by prolonged dark incubation at supraoptimal temperature, and also by drying treatments. The physical (surgical) treatments, such as cutting the tip of achenes or removal of the pericarp, promoted germination of unchilled achenes, while chemical treatments with calcium hypochlorite, and nitrogenous compounds such as nitrates, thiourea, hydroxylamine hydrochloride, and respiratory inhibitors like cyanide and azide, failed to break the dormancy of unchilled achenes. However, unchilled achenes responded positively to treatment with nitrite and hydrogen peroxide, giving an enhanced and significant germination. Treatment with environmental factors such as temperature and light (white or red) on unchilled achenes illustrated that the population consists of at least four physiological polymorphic components, namely. Dark; Light; Alternating Temperature (dark), and Alternating Temperature plus Light subpopulations. Stratification treatment resulting in complete dark germination when transferred to higher temperature is more effective at 4°C than 10°C. Germination is enhanced at alternating temperatures in the dark in contrast to constant temperatures. However, a high temperature of 40°C is lethal for germination. Exogenous application of GA3, GA4+7, ethylene or nonanoic acid (C9) did not influence the germination of unchilled achenes. In contrast, kinetin appears to promote germination. Moreover, combined treatments of red light and kinetin with or without GA3 gave the greatest germination. Results from applying G3 during or after stratification did not indicate the involvement of gibberellin during or after chilling. Also, treatment with growth retardants (B995, CCC, AMO 1618, and Ancymidol) argue against gibberellin involvement during or after stratification. The results of applying ABA during stratification or germination indicated that growth processes, i.e. radicle elongation, are inhibited and not germination sensu stricto. The results of, prolonged dark incubation at supraoptimal temperature at 40°C indicated that the effect could be considered as thermo inhibition rather than thermodormancy. However, drying treatment induces secondary dormancy.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Plant sciences.
• Subjects: Q Science > QK Botany; S Agriculture > SB Plant culture
• Colleges/Schools: College of Science and Engineering
• Supervisor's Name: Berrie, Dr. A.M.M.
• Date of Award: 1984
• Depositing User: Enlighten Team
• Unique ID: glathesis:1984-71552
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 10 May 2019 14:19
• Last Modified: 07 Nov 2022 14:18
• Thesis DOI: 10.5525/gla.thesis.71552
• URI: https://theses.gla.ac.uk/id/eprint/71552