Summary
Three pericycle cell types (opposite xylem, opposite phloem and intervening) distinguished by their location in relation to different elements of the vascular system were studied in the adventitious root ofAllium cepa L. Changes in cell length and mitotic index were analysed in these cells along the apical meristem and elongation zone of the root. The opposite phloem and intervening pericycle cells are significantly shorter than the opposite xylem pericycle cells in the apical half of the meristem. Between 1,200 and 1,400 μm behind the tip, length became similar in all three pericycle cell types, while in more proximal zones the opposite phloem cells were significantly longer. These results suggest that the number of transverse divisions is different in the three types of pericycle cells. In the apical half of the meristem, mitotic index increased in intervening and opposite xylem cells but remained unchanged in opposite phloem cells, a fact likely to account for the relative lengthening of the latter. In the proximal half of the meristem, mitotic index fell in all three cell types until cell division had ceased. However, mitotic index in opposite xylem cells remained high for longer than in the other two cell types, implying that increase of the mean cell length in the former was slower. These results suggest that differences in mean cell length between the three pericycle cell types are due to different rates of proliferation.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Allan EF, Trewavas A (1986) Tissue-dependent heterogeneity of cell growth in the root apex ofPisum sativum. Bot Gaz 147: 258–269
Balodis VA (1968) Some aspects of mitosis distribution in the root tip. Tsitologiya 10: 1374–1383
Barlow PW (1984) Positional controls in root development. In: Barlow PW, Carr DJ (eds) Positional controls in plant development. Cambridge University Press, Cambridge, pp 281–318
—, Adam JS (1988) The position and growth of lateral roots on cultured root axes of tomato,Lycopersicon esculentum (Solanaceae). Plant Syst Evol 158: 141–154
Bell JK, McCully ME (1970) A histological study of lateral root initiation and development inZea mays. Protoplasma 70: 179–205
Bertaud DS, Gandar PW (1986) A simulation model for cell proliferation in root apices. II. Patterns of cell proliferation. Ann Bot 58: 303–320
— —, Erickson RO, Ollivier AM (1986) A simulation model for cell growth and proliferation in root apices. I. Structure of model and comparison with observed data. Ann Bot 58: 285–301
Casero PJ, García-Sánchez C, Lloret PG, Navascués J (1989) Morphological features of pericycle cells in relation to their topographical location in onion adventitious roots. New Phytol (in press)
Charlton WA (1982) Distribution of lateral root primordia in root tips ofMusa acuminata Colla. Ann Bot 49: 509–520
Erickson RO (1959) Patterns of cell growth and differentiation in plants. In: Brachet J, Mirsky AE (eds) The cell, vol 1. Academic Press, New York, pp 497–535
—, Sax KB (1956) Rates of cell division and cell elongation in the growth of the primary root ofZea mays. Proc Am Phil Soc 100: 499–514
Esau K (1940) Developmental anatomy of the fleshy storage organ ofDaucus carota. Hilgardia 13: 175–226
Fahn A (1982) Plant anatomy, 3rd edn. Pergamon Press, Oxford
Green PB (1984) Analysis of axis extension. In: Barlow PW, Carr DJ (eds) Positional controls in plant development. Cambridge University Press, Cambridge, pp 53–82
Goodwin RH, Avers CJ (1956) Studies on roots. III. An analysis of root growth inPhleum pratense using photomicrographic records. Am J Bot 43: 479–487
Jensen WA, Kavaljian LG (1958) An analysis of cell morphology and the periodicity of division in the root tip ofAllium cepa. Am J Bot 45: 365–372
Lloret PG, Casero PJ, Pulgarin A, Navascués J (1989) The behaviour of two cell populations in the pericycle ofAllium cepa, Pisum sativum, andDaucus carota during early lateral root development. Ann Bot (in press)
Luxová M (1975) Some aspects of the differentiation of primary root tissues. In: Torrey JG, Clarkson DT (eds) The development and function of roots. Academic Press, New York, pp 73–90
McCully ME (1975) The development of lateral roots. In: Torrey JG, Clarkson DT (eds) The development and function of roots. Academic Press, New York, pp 105–124
Peterson RL, Peterson CA (1986) Ontogeny and anatomy of lateral roots. In: Jackson MB (ed) New root formation in plants and cuttings. Martinus Nijhoff, Boston, pp 1–30
Popham RA (1955) Zonation of primary and lateral root apices ofPisum sativum. Am J Bot 42: 267–273
Pulgarin A, Navascués J, Casero PJ, Lloret PG (1988) Branching pattern in onion adventitious roots. Am J Bot 75: 425–432
Rost TL, Jones TJ, Falk RH (1988) Distribution and relationship of cell division and maturation events inPisum sativum (Fabaceae) seedling roots. Am J Bot 75: 1571–1583
Torrey JG (1952) Effects of light on elongation and branching in pea roots. Plant Physiol 27: 591–602
Van Tieghem P, Douliot H (1988) Recherches comparatives sur l'origine des membres endogenes dans les plantes vasculaires. Ann Sci Natur (Bot) 7th serie 8: 1–660
Webster PL, MacLeod RD (1980) Characteristics of root apical meristem cell population kinetic: a review of analyses and concepts. Environ Exp Bot 20: 335–358
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Casero, P.J., García-Sánchez, C., Lloret, P.G. et al. Changes in cell length and mitotic index in vascular pattern-related pericycle cell types along the apical meristem and elongation zone of the onion root. Protoplasma 153, 85–90 (1989). https://doi.org/10.1007/BF01322468
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01322468