Web URL(s): https://link.springer.com/article/10.1023/A%3A1004534609280 Publication Type:
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Refereed Author(s): Mackie-Dawson, L. A. Author Affiliation: Macaulay Land USe Research Institute, Craigiebuckler, Aberdeen, UK Title: Nitrogen uptake and root morphological responses of defoliated Lolium perenne (L.) to a heterogeneous nitrogen supply Source: Plant and Soil . Vol. 209, No. 1, 1999, p. 111-118.# of Pages: 8 Publishing Information: Dordrecht, Netherlands: Kluwer Academic Publishers Keywords: TIC Keywords: Nitrogen uptake ; Morphology ; Roots ; Lolium perenne ; Defoliation ; Grassland soils ; Responses ; Root inhibition ; Root growth ; Distribution patterns ; Turfgrass quality ; Tillers (vegetative) ; Biomass Cultivar Names: Magella Abstract/Contents: "Lolium perenne L. (c.v. Magella) plants were grown under three nutrient treatments for six weeks and then defoliated to test the hypothesis that for their regrowth they could acquire N equally well irrespective of N distribution. Two different N levels were applied; uniform level 1 N (U1), uniform level 2 (U2) and heterogeneous level 2 (H2). A system where the nutrient patch could be applied without barrier to root growth was adopted. A single defoliation to 4 cm height resulted in reduction in tillering, biomass increment and N uptake at 3 weeks after defoliation. Root growth was reduced by defoliation under all N treatments. Defoliation was found to reduce the proportion of N in the shoots which was derived from root uptake from 7 to 14 days. At 21 days this effect was significant for the plants with a heterogeneously distributed supply only. By the end of the regrowth period, the undefoliated plants from H2 had a shoot biomass and N content equal to that of the plants receiving the same total N but supplied homogeneously (U2). However, defoliation reduced the ability of the plant to acquire N from the patch. No preferential root growth was measured into the N-rich patch, but an increased root diameter within the patch was found. Root diameter was reduced by defoliation, coinciding with a reduction in the concentration of N in the root tissue. As a result of the increased sink strength of the growing leaves after defoliation, the roots may become a source of carbon and also nitrogen. These responses to an N-rich patch under defoliation could alter a plant's competitive balance in a mixed sward." Language: English References: 43 Note: Tables ASA/CSSA/SSSA Citation (Crop Science -Like - may be incomplete ): Lolium perenne (L.) to a heterogeneous nitrogen supply. Plant Soil. 209(1):p. 111-118.Fastlink to access this record outside TGIF: https://tic.msu.edu/tgif/flink?recno=61474 If there are problems with this record, send us feedback about record 61474 . Choices for finding the above item : Web URL(s): https://link.springer.com/article/10.1023/A%3A1004534609280 SB 13 .P55 Find from within TIC: Request through your local library's inter-library loan service (bring or send a copy of this TGIF record)
