Root Development in the Grassland Formation, a Correlation of the Root Systems of Native Vegetation and Crop Plants
            . By John E. Weaver. Carnegie Inst. Washington Publ. 292. 18 × 26 cm., 151 pp., 25 p1., 39 text fig. Washington, 1920.

Fall panicum (Panicum dichotomiflorum Michx.) and Texas panicum (Panicum texanum Buckl.) were grown in the greenhouse under flooding treatments of 0, 6, and 9 days in 10 for 1 month. Fall panicum was more tolerant of flooded soil than was Texas panicum. Root development of Texas panicum was reduced by 50% under all flooding treatments. Herbage and root growth of fall panicum with flooding was similar to that on well-drained soil. Fall panicum root diameter was greater than that of Texas panicum, but both species increased under flooding. Tolerance of fall panicum to flooding may partially explain why it competes so well with crop plants during wet periods.

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Nitrate Uptake and Partitioning by Corn {Zea maysL.) Root Systems and Associated Morphological Differences among Genotypes and Stages of Root Development

Journal of Experimental Botany ◽

10.1093/jxb/36.9.1341 ◽

1985 ◽

Vol 36 (9) ◽

pp. 1341-1351 ◽

Cited By ~ 25

Author(s):

W. L. PAN ◽

W. A. JACKSON ◽

R. H. MOLL

Keyword(s):

Root Development ◽

Nitrate Uptake ◽

Root Systems ◽

Morphological Differences

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Pisolithus tinctorius forms long ectomycorrhizae and alters root development in seedlings of Pinus resinosa

Canadian Journal of Botany ◽

10.1139/b81-277 ◽

1981 ◽

Vol 59 (11) ◽

pp. 2129-2134 ◽

Cited By ~ 13

Author(s):

Richard F. Sohn

Keyword(s):

Growth Rate ◽

Root Development ◽

Lateral Root ◽

Pinus Resinosa ◽

Root Systems ◽

Pisolithus Tinctorius ◽

Third Order ◽

Lateral Root Development ◽

Mycorrhiza Formation

Ectomycorrhizae were synthesized on Pinus resinosa seedlings with Pisolithus tinctorius under aseptic, controlled environmental conditions. Root systems were harvested at 4, 6, and 15 weeks after seed germination. All roots were classified as either long or short and were examined for ectomycorrhiza development. Mycorrhizae were classified as "long mycorrhizae" or "short mycorrhizae," depending upon the type of root where infection occurred.Long mycorrhizae predominated at the early harvests and remained prominent at 15 weeks. A Hartig net of long mycorrhizae formed a morphological continuum from thin to thick. Negative correlations were observed between long mycorrhiza growth rate and the extent of infection. This suggests that a threshold growth rate exists below which mycorrhiza formation occurs readily, but above which mycorrhiza formation is progressively diminished. Relative to the controls, P. tinctorius inoculation increased the ratio of second- and third-order short roots to long roots. The role of host and fungus in controlling lateral root development is discussed.

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Root Systems of Crop Plants

Journal of Ecology ◽

10.2307/2255745 ◽

1922 ◽

Vol 10 (2) ◽

pp. 239

Author(s):

A. G. T. ◽

John E. Weaver ◽

Frank C. Jean ◽

John W. Crist

Keyword(s):

Root Systems ◽

Crop Plants

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Root mapping of three tropical pasture species using 32P

Australian Journal of Experimental Agriculture ◽

10.1071/ea9690445 ◽

1969 ◽

Vol 9 (39) ◽

pp. 445 ◽

Cited By ~ 2

Author(s):

RA Bray ◽

JB Hacker ◽

DE Byth

Keyword(s):

Root Growth ◽

Root Development ◽

Lateral Root ◽

Sandy Loam ◽

Lateral Roots ◽

Root Systems ◽

Growth Patterns ◽

Constant Rate ◽

Initial Root

Root growth patterns of Glycine javanica, Setaria anceps, and Medicago sativa were studied by uptake of 32P from a sandy loam. Placement of isotope was through permanently positioned PVC conduit on a grid over a 90� quadrant of the root system. Detection of radioactivity was in in situ plant material. Lucerne had strong initial root development but was slow to form lateral roots. Glycine and Setaria had quite similar root systems although Setaria had more rapid vertical root development than Glycine. Both these species had strong lateral root systems. When a regression of minimum root length against time was calculated, lateral root growth was shown to be independent of depth and distance from the plant, suggesting that roots behave as if growing from a point source in random directions at a constant rate. This rate was the same for all species. There were also indications of strong vertical root systems in lucerne and Setaria.

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