GROWTH, DRY MATTER ALLOCATION AND SENESCENCE OF DARK-GROWN COMMON BEAN SEEDLINGS
Dark-grown seedlings show to high degree the etiolation syndrome, which depends exclusively upon the seed reserves and the water absorbed by the roots. The objective of the present research was to describe the growth and dry matter allocation of the etiolated bean (Phaseolus vulgaris L.) seedling from germination to its demise by exhaustion of its nutritional reserves. In addition, we describe the senescence process of the seedling. The experiment was repeated three times, with slight variations among them, under complete darkness, with the common bean cv. Cacahuate-72. Observations and samplings were undertaken at various ages of the seedling. The growth was very fast and was represented by a sigmoid curve. Of the various parts of the seedling the hypocotyl showed both the highest rate of elongation (5.2 cm d-1) and of dry matter accumulation (4.7 mg d-1). The plumular hook opened after the completion of epicotyl elongation. Senescence of the root and the various structures of the shoot occurred after their growth (as length, dry matter, or also number in the case of roots) ended. The sequence of senescence was: cotyledons, primary leaf blades, petioles, apical bud, hypocotyl base, adventitious roots, secondary roots and main root.
| Main Authors: | , , , |
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| Format: | Digital revista |
| Language: | spa |
| Published: |
Colegio de Postgraduados
1999
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| Online Access: | https://www.agrociencia-colpos.org/index.php/agrociencia/article/view/1615 |
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