Getting more bark for your buck: nitrogen economy of deciduous forest trees

This article comments on: Li G, Lin R, Egekwu C, Blakeslee J, Lin J, Pettengill E, Murphy AS, Peer WA, Islam N, Babst BA, Gao F, Komarov S, Tai Y-C, Coleman GD. 2020. Seasonal nitrogen remobilization and the role of auxin transport in poplar trees. Journal of Experimental Botany 71, 4512–4530.

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Seasonal nitrogen remobilization and the role of auxin transport in poplar trees

Journal of Experimental Botany ◽

10.1093/jxb/eraa130 ◽

2020 ◽

Vol 71 (15) ◽

pp. 4512-4530

Author(s):

Gen Li ◽

Rongshoung Lin ◽

Chioma Egekwu ◽

Joshua Blakeslee ◽

Jinshan Lin ◽

...

Keyword(s):

Shoot Growth ◽

Auxin Transport ◽

Storage Proteins ◽

Protease Gene ◽

Nitrogen Remobilization ◽

Poplar Trees ◽

N Partitioning ◽

Bark Storage Proteins ◽

N Remobilization

Abstract Seasonal nitrogen (N) cycling in Populus, involves bark storage proteins (BSPs) that accumulate in bark phloem parenchyma in the autumn and decline when shoot growth resumes in the spring. Little is known about the contribution of BSPs to growth or the signals regulating N remobilization from BSPs. Knockdown of BSP accumulation via RNAi and N sink manipulations were used to understand how BSP storage influences shoot growth. Reduced accumulation of BSPs delayed bud break and reduced shoot growth following dormancy. Further, 13N tracer studies also showed that BSP accumulation is an important factor in N partitioning from senescing leaves to bark. Thus, BSP accumulation has a role in N remobilization during N partitioning both from senescing leaves to bark and from bark to expanding shoots once growth commences following dormancy. The bark transcriptome during BSP catabolism and N remobilization was enriched in genes associated with auxin transport and signaling, and manipulation of the source of auxin or auxin transport revealed a role for auxin in regulating BSP catabolism and N remobilization. Therefore, N remobilization appears to be regulated by auxin produced in expanding buds and shoots that is transported to bark where it regulates protease gene expression and BSP catabolism.

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Sensing when the wall comes tumbling down

Journal of Experimental Botany ◽

10.1093/jxb/eraa436 ◽

2020 ◽

Vol 71 (22) ◽

pp. 6865-6868

Author(s):

David A Brummell

Keyword(s):

Fruit Softening ◽

Strawberry Fruit ◽

Experimental Botany

This article comments on: Paniagua C, Ric-Varas P, Garcia-Gago JA, López-Casado G, Blanco-Portales R, Muñoz-Blanco J, Schückel J, Knox JP, Matas AJ, Quesada MA, Posé S, Mercado JA. 2020. Elucidating the role of polygalacturonase genes in strawberry fruit softening. Journal of Experimental Botany 71, 7103–7117.

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Maturation-related loss in rooting competence by loblolly pine stem cuttings: The role of auxin transport, metabolism and tissue sensitivity

Physiologia Plantarum ◽

10.1111/j.1399-3054.1996.tb00507.x ◽

1996 ◽

Vol 97 (3) ◽

pp. 481-490 ◽

Cited By ~ 44

Author(s):

Carmen Diaz-Sala ◽

Keith W. Hutchison ◽

Barry Goldfarb ◽

Michael S. Greenwood

Keyword(s):

Loblolly Pine ◽

Auxin Transport ◽

Stem Cuttings ◽

Tissue Sensitivity ◽

Rooting Competence

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The Role of Termites in Soil Formation in the Tropical Semi-Deciduous Forest Zone, Ghana

Geografisk Tidsskrift-Danish Journal of Geography ◽

10.1080/00167223.2004.10649516 ◽

2004 ◽

Vol 104 (2) ◽

pp. 27-34 ◽

Cited By ~ 13

Author(s):

Theodore W. Awadzi ◽

M. A. Cobblah ◽

Henrik Breuning-Madsen

Keyword(s):

Deciduous Forest ◽

Soil Formation ◽

Forest Zone

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The Role of Ectomycorrhizal Symbiosis in the Resistance of Forests to Water Stress

Outlook on Agriculture ◽

10.5367/000000000101293068 ◽

2000 ◽

Vol 29 (1) ◽

pp. 63-69 ◽

Cited By ~ 18

Author(s):

Jean Garbaye

Keyword(s):

Water Stress ◽

Sustainable Management ◽

Fine Roots ◽

Forest Ecosystems ◽

Water Status ◽

Forest Trees ◽

Direct Effects ◽

Ectomycorrhizal Symbiosis ◽

Protection Mechanisms

Forest trees live in enforced symbiosis with specialized fungi that form composite organs (ectomycorrhizas) with fine roots. This paper examines how this association contributes to the water status of trees and how it plays a major role in the protection mechanisms by which trees and forest stands resist drought-induced water stress. It shows how ectomycorrhizal symbiosis has both direct effects (at the uptake level) and indirect effects (at the regulation level) on the water status of trees. The facts presented are discussed in terms of forest adaptation to changing environmental conditions and the practical consequences for the sustainable management of forest ecosystems.

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Huftiere und Verjüngung im Gebirgswald: eine Geschichte mit vielen Variablen und noch mehr Interaktionen | Ungulates and Tree Regeneration in Mountain Forests: an Issue with many Variables and even more Interactions

Schweizerische Zeitschrift fur Forstwesen ◽

10.3188/szf.2000.0099 ◽

2000 ◽

Vol 151 (4) ◽

pp. 99-106 ◽

Cited By ~ 4

Author(s):

Josef Senn

Keyword(s):

Tree Regeneration ◽

Small Scale ◽

Mountain Forest ◽

Forest Trees ◽

Mountain Forests ◽

Wild Ungulates ◽

Site Factors ◽

The Past

After excessive cutting in Swiss mountain forests and extirpation of most of the wildlife during the past centuries, efficient forestry and hunting laws allowed a wide regeneration of the forests and a rapid increase of ungulate populations in the present century. As a consequence, the impacts of ungulates on the vegetation became obvious. Regeneration of forest trees, however, is influenced not only by ungulates, but by a number of physical site factors and biotic impacts. As these impacts and their interactions vary extensively, regeneration is neither spatially nor temporally constant. Most of the presently used tree-regeneration methods, however, assume constant conditions, which renders a proper evaluation of tree regeneration in mountain forests and the role of ungulates impossible. Furthermore, the effect of this variation on forest development and forest functions is unknown with regard to the long term. While society requires a multipurpose mountain forest, structured at a small scale, wild ungulates use their habitat at a larger scale. This often leads to conflicts. Consequently,solutions including different scales are necessary. A lack of knowledge will, therefore, have to be met by research making data available to the practice as well as through coordinated investigations and experiments.

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