Abstract
The direction of root growth can be studied by analyzing the trajectories of roots growing in soil. Both the primary seminal root and nodal roots of maize attain a preferred, or liminal, angle of growth that deviates from the vertical. These roots are said to be plagiogravitropic. Experiments using plants grown in soil-filled boxes revealed that the primary seminal root is truly plagiogravitropic. It shows both positive and negative gravitropism in response to gravity stimuli and tends to maintain its direction even after growing around obstacles. These are experimental results suggesting that plagiogravitropic growth is controlled by internal factors. The orientation of the grain affects the establishment of the liminal angle of the primary seminal root, and both the position of their node of origin and the root diameter are closely related to the plagiogravitropic behaviour of nodal roots. Several external factors are also known to influence plagiogravitropism. Low soil water content causes a decrease in the angle of growth and soil mechanical resistance suppresses the gravitropic curvature. Plagiogravitropic behaviour of both seminal and nodal roots plays a significant role in shaping the root system.
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References
Barlow P W 1992 A conceptual framework for investigating plant growth movements, with special reference to root gravitropism, utilizing a microgravity environment. Microgravity Quart. 2, 77–87.
Barlow P W and Zieschang E 1994 Root movements: towards an understanding through attempts to model the processes involved. Plant and Soil (This volume).
Horwitz B A and Zur B 1991 Gravitropic response of primary maize rootlets as influenced by light and temperature. Plant Cell Environ. 14, 619–623.
Jackson M B and Barlow P W 1981 Root geotropism and the role of growth regulators from the cap: a reexamination. Plant Cell Environ. 4, 107–123.
Kutschera L 1983 Wurzeltropismen als Funktion der Wasserabgabe und Aufnahme: Die “Wassertheorie”. In Wurzelökologie und ihre Nutszanwendung. Int. Symp. Gumpenstein 1982. pp 301–322. Bundesanstalt Gumpenstein, Irdning, Austria.
Lachno D R, Harison-Murray R S and Audus L J 1982 The effects of mechanical impedance to growth on the levels of ABA and IAA in root tips of Zea mays L. J. Exp. Bot. 33, 943–951.
Leopold A C and LaFavre A K 1989 Interactions between red light, abscisic acid, and calcium in gravitropism. Plant Physiol. 89, 875–878.
Moore R and Pasieniuk J 1984 Graviresponsiveness and the development of columella tissue in primary and lateral roots of Ricinus communis. Plant Physiol. 74, 529–533.
Mosher P N and Miller M H 1972 Influence of soil temperature on the geotropic response of corn roots (Zea mays L.). Agron. J. 647, 459–462.
Nakamoto T 1993 Effect of soil water content on the gravitropic behavior of nodal roots in maize. Plant and Soil 152, 261–267.
Nakamoto T and Oyanagi A 1994 The direction of growth of seminal roots of Triticum aestivum L. and experimental modification thereof. Ann. Bot. 73, 363–367.
Nakamoto T, Shimoda K and Matsuzaki A 1991 Elongation angle of nodal roots and its possible relation to spatial root distribution in maize and foxtail millet. Jpn. J. Crop Sci. 60, 543–549.
Ney D and Pilet P-E 1980 Importance of the caryopsis in root growth and georeaction. Physiol. Plant. 50, 166–168.
Onderdonk J J and Ketcheson J W 1973 Effect of soil temperature on direction of corn root growth. Plant and Soil 39, 177–186.
Oyanagi A, Nakamoto T and Morita S 1993 The gravitropic response of roots and the shaping of the root system in cereal plants. Environ. Exp. Bot. 33, 141–158.
Oyanagi A, Sato A and Wada M 1992 Effect of water potential of culture medium on geotropic response of primary seminal root in Japanese wheat cultivars. Jpn. J. Crop Sci. 61, 119–123.
Porodko Th M 1924 Uber den Diageotropismus der Hauptwurzeln bei Maiskeimlingen. I. Ber. Dtsch. Bot. Ges. 42, 405–412.
Porodko Th M 1924 Uber den Diageotropismus der Hauptwurzeln bei Maiskeimlingen. II. Ber. Dtsch. Bot. Ges. 42, 413–419.
Ransom J S and Moore R 1985 Geoperception in primary and lateral roots of Phaseolus vulgaris (Fabaceae). III. A model to explain the differential georesponsiveness of primary and lateral roots. Can. J. Bot. 63, 21–24.
Rufelt H 1962 Plagiogeotropism in roots. In Encyclopedia of Plant Physiology, Vol. 17/2. Ed. W Ruhland. pp 322–343. Springer-Verlag, Berlin.
Sheppard S C and Miller M H 1977 Temperature changes and the geotropic reaction of the radicle of Zea mays L. Plant and Soil 47, 631–644.
Tardieu F and Pellerin S 1991 The influence of soil temperature during root appearance on the trajectory of maize roots in the field. Plant and Soil 131, 207–214.
Varney G T, Canny M J, Wang X L and McCully M E 1991 The branch roots of Zea. I. First order branches, their number, sizes and division into classes. Ann. Bot. 67, 357–364.
Wilson B F 1967 Root growth around barriers. Bot. Gaz. 128, 79–82.
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Nakamoto, T. Plagiogravitropism of maize roots. Plant Soil 165, 327–332 (1994). https://doi.org/10.1007/BF00008077
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DOI: https://doi.org/10.1007/BF00008077