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The effect of maturity on the moisture relations of seed longevity in foxglove (Digitalis purpurea L.)

Published online by Cambridge University Press:  19 September 2008

F.R. Hay*
Affiliation:
Seed Conservation Section, Jodrell Laboratory, Royal Botanic Gardens Kew, Wakehurst Place, Ardingly, W. Sussex, RH17 6TN, UK
R.J. Probert
Affiliation:
Seed Conservation Section, Jodrell Laboratory, Royal Botanic Gardens Kew, Wakehurst Place, Ardingly, W. Sussex, RH17 6TN, UK
R. D. Smith
Affiliation:
Seed Conservation Section, Jodrell Laboratory, Royal Botanic Gardens Kew, Wakehurst Place, Ardingly, W. Sussex, RH17 6TN, UK
*
*Correspondence

Abstract

Controlled aging experiments were carried out in order to evaluate the changes in seed longevity occurring following the attainment of maximum seed dry weight in foxglove (Digitalis purpurea L.). Seeds harvested in three successive years were stored at ~5% moisture content (fresh weight basis) and 50°C. Seed longevity was greater the later the seeds were harvested. When the data were modelled using the predictive viability model of Ellis and Roberts, these increases were attributable to increases in both the theoretical initial viability (in probits) of the seed-lot, Ki, and in the standard deviation of the normal distribution of seed deaths in time, σ. Furthermore, there was a positive relationship between Ki and σ which was independent of the year of harvest (r = 0.9016, for 11 d.f., P < 0.001). These results do not support the predictive model which relies on the assumption that σ will not differ between seed lots of the same species stored under identical conditions. When seeds were stored at a range of moisture contents (between 5 and 10%) at 50°C, increases in σ during seed development were manifest as changes in the negative logarithmic relationship between σ and moisture content; below an upper limit, the regressions for seed lots at different stages of maturity were significantly different (P < 0.05) but could be constrained to either a common intercept or to a common slope (P < 0.05). It is proposed that it was the inherent variation in individual seed lifespans which increased during seed development. These results raise important concerns regarding the use of predetermined ‘species constants’ to predict the longevity of seed lots during long-term storage in seed banks.

Type
Physiology and Biochemistry
Copyright
Copyright © Cambridge University Press 1997

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References

Demir, I. and Ellis, R.H. (1992a) Development of pepper (Capsicum annuum) seed quality. Annals of Applied Biology 121, 385399.CrossRefGoogle Scholar
Demir, I. and Ellis, R.H. (1992b) Changes in seed quality during seed development and maturation in tomato. Seed Science Research 2, 8187.CrossRefGoogle Scholar
Demir, I. and Ellis, R.H. (1993) Changes in potential seed longevity and seedling growth during seed development and maturation in marrow. Seed Science Research 3, 247257.CrossRefGoogle Scholar
Dickie, J.B., Ellis, R.H., Kraak, H.L., Ryder, K. and Tompsett, P.B. (1990) Temperature and seed storage longevity. Annals of Botany 65, 197204.CrossRefGoogle Scholar
Ellis, R.H. and Roberts, E.H. (1980a) Improved equations for the prediction of seed longevity. Annals of Botany 45, 1330.CrossRefGoogle Scholar
Ellis, R.H. and Roberts, E.H. (1980b) The influence of temperature and moisture on seed viability period in barley (Hordeum distichum L.). Annals of Botany 45, 3137.CrossRefGoogle Scholar
Ellis, R.H., Hong, T.D. and Roberts, E.H. (1986) Logarithmic relationship between moisture content and longevity in sesame seeds. Annals of Botany 57, 499503.CrossRefGoogle Scholar
Ellis, R.H., Hong, T.D. and Roberts, E.H. (1988) A low-moisture-content limit to logarithmic relations between seed moisture content and longevity. Annals of Botany 61, 405408.CrossRefGoogle Scholar
Ellis, R.H., Hong, T.D. and Roberts, E.H. (1989) A comparison of the low-moisture-content limit to the logarithmic relation between seed moisture and longevity in twelve species. Annals of Botany 63, 601611.CrossRefGoogle Scholar
Ellis, R.H., Hong, T.D. and Roberts, E.H. (1990a) Moisture content and the longevity of seeds of Phaseolus vulgaris. Annals of Botany 66, 341348.CrossRefGoogle Scholar
Ellis, R.H., Hong, T.D., Roberts, E.H. and Tao, K.-L. (1990b) Low moisture content limits to relations between seed longevity and moisture. Annals of Botany 65, 493504.CrossRefGoogle Scholar
Ellis, R.H., Hong, T.D. and Jackson, M.T. (1993) Seed production environment, time of harvest, and the potential longevity of seeds of three cultivars of rice (Oryza sativa L.). Annals of Botany 72, 583590.CrossRefGoogle Scholar
Francis, B., Green, M. and Payne, C. (1993) The CLIM system: Release 4 manual. Oxford, Clarendon Press.CrossRefGoogle Scholar
Hay, F.R. (1997) The development of seed longevity in wild plant species. PhD Thesis, University of London, UK.Google Scholar
Hay, F.R. and Probert, R.J. (1995) Seed maturity and the effects of different drying conditions on desiccation tolerance and seed longevity in foxglove (Digitalis purpurea L.). Annals of Botany 76, 639647.CrossRefGoogle Scholar
Hay, F.R., Probert, R.J. and Coomber, S.A. (1997) Development of desiccation tolerance and longevity in seeds from detached capsules of foxglove (Digitalis purpurea L.). Annals of Botany 79, 419427.CrossRefGoogle Scholar
Ibrahim, A.E. and Roberts, E.H. (1983) Viability of lettuce seeds. I. Survival in hermetic storage. Journal of Experimental Botany 34, 620630.CrossRefGoogle Scholar
Ibrahim, A.E., Roberts, E.H. and Murdoch, A.J. (1983) Viability of lettuce seeds. II. Survival and oxygen uptake in osmotically controlled storage. Journal of Experimental Botany 34, 631640.CrossRefGoogle Scholar
ISTA (1985) International rules for seed testing. Rules 1985. Seed Science and Technology 13, 356513.Google Scholar
Kameswara Rao, N., Appa Rao, S., Mengesha, M.H. and Ellis, R.H. (1991) Longevity of pearl millet (Pennisetum glaucum R.Br.) seeds harvested at different stages of maturity. Annals of Applied Biology 119, 97103.Google Scholar
Pieta Filho, C. and Ellis, R.H. (1991) The development of seed quality in spring barley in four environments. I. Germination and longevity. Seed Science Research 1, 163177.CrossRefGoogle Scholar
Probert, R.J., Bogh, S.V., Smith, A.J. and Wechsberg, G.E. (1991) The effects of priming on seed longevity in Ranunculus sceleratus L. Seed Science Research 1, 243249.CrossRefGoogle Scholar
Roberts, E.H. (1973) Predicting the storage life of seeds. Seed Science and Technology 1, 499514.Google Scholar
Roberts, E.H. and Ellis, R.H. (1982) Physiological, ultrastructural and metabolic aspects of seed viability. pp 465485in Khan, A.A. (Ed.) The physiology and biochemistry of seed development, dormancy and germination. Amsterdam, New York, Oxford, Elsevier Biomedical Press.Google Scholar
Roberts, E.H. and Ellis, R.H. (1989) Water and seed survival. Annals of Botany 63, 3952.CrossRefGoogle Scholar
Vertucci, C.W. and Roos, E.E. (1990) Theoretical basis of protocols for seed storage. Plant Physiology 94, 10191023.CrossRefGoogle ScholarPubMed
Vertucci, C.W. and Roos, E.E. (1993) Theoretical basis of protocols for seed storage. II. The influence of temperature on optimum moisture levels. Seed Science Research 3, 201213.CrossRefGoogle Scholar
Vertucci, C.W., Roos, E.E. and Crane, J. (1994) Theoretical basis of protocols for seed storage. III. Optimum moisture contents for pea seeds stored at different temperatures. Annals of Botany 74, 531540.CrossRefGoogle Scholar
Wechsberg, G.E., Probert, R.J. and Bray, C.M. (1994) The relationship between ‘dehydrin-like’ proteins and seed longevity in Ranunculus sceleratus L. Journal of Experimental Botany 45, 10271030.CrossRefGoogle Scholar
Winston, P.W. and Bates, D.H. (1960) Saturated solutions for the control of humidity in biological research. Ecology 41, 232237.CrossRefGoogle Scholar
Zanakis, G.N., Ellis, R.H. and Summerfield, R.J. (1994) Seed quality in relation to seed development in three genotypes of soybean (Glycine max). Experimental Agriculture 30, 139156.CrossRefGoogle Scholar
Zewdie, M. and Ellis, R.H. (1991a) The upper moisture content limit to negative relations between seed longevity and moisture in niger and tef. Seed Science and Technology 19, 295302.Google Scholar
Zewdie, M. and Ellis, R.H. (1991b) Response of tef and niger seed longevity to storage temperature and moisture. Seed Science and Technology 19, 319329.Google Scholar