Morphological and symbiotic root modifications for mineral acquisition from nutrient-poor soils
- Authors: Kleinert, Aleysia , Benedito, V A , Morcillo, R J L , Dames, Joanna F , Cornejo-Rivas, P , Zuniga-Feest, A , Delgado, Mabel , Muñoz, Gaston
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448640 , vital:74748 , https://doi.org/10.1007/978-3-319-75910-4_4
- Description: Plants have the ability to form vast root systems with lengths measuring up to several kilometers and branch roots numbering in millions. These expansive root systems provide plants with a large surface area for water and nutrient uptake from the surrounding soil. Roots also have further equally important functions to fulfil such as vegetative reproduction, hormone biosynthesis, photoassimilate storage, and the establishment of symbiotic relationships with microorganisms. Root systems have evolved several adaptations to aid them in maximizing nutrient uptake. These adaptations can be morphological such as changes in the root architecture or formation of cluster roots or may be symbiotic associations with mycorrhizae or nitrogen-fixing bacteria. Improvement of nutrient acquisition and use by plants is imperative for economic, humanitarian, and environmental reasons, and a better understanding of the processes governing root adaptations would enable us to adapt fertilizer and pesticide programs. In this chapter, we will focus on both morphological (cluster roots) and symbiotic root adaptations (associations with ectomycorrhizae, arbuscular mycorrhizae, and nitrogen-fixing bacteria) to soil nutrient deficiencies.
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- Date Issued: 2018
Physiology and Spatio-temporal Relations of Nutrient Acquisition by Roots and Root Symbionts
- Authors: Valentine, Alex J , Kleinert, Aleysia , Thuynsma, Rochelle , Chimphango, Samson , Dames, Joanna F , Benedito, V A
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448652 , vital:74749 , https://doi.org/10.1007/124_2016_11
- Description: Among the various functions of roots, nutrient acquisition (via soil uptake or through symbiotic relationships) is one of the most essential for land plants. Soil from natural and agricultural ecosystems may impede plant nutrient acquisition, by many factors such as mineral availabilities either in excess or deficient supply, depletion of organic matter, extreme variations in water supply, and many other physical and chemical features. In order to survive, plants need to undergo developmental and physiological mechanisms to cope with these extreme soil situations. Here we review how plants control nutrient acquisition by dynamically changing root architecture for improved soil space exploration, as well as altering cellular-level function for enhanced nutrient uptake, via apoplastic acidification, exudation of enzymes and metabolites (organic acids, secondary metabolites) and constantly changing the composition of transporters at the plasma membrane. These changes start with environmental cues which induce cell signaling and involve hormones and coordinated regulatory genes networks that drive the root’s developmental plasticity as well as the cell’s biochemical dynamics. Mutualistic root symbioses, such as mycorrhizae and rhizobial-induced nodulation, are also important to provide essential nutrients to the plant, which are tightly regulated in order to only occur at plant’s benefit. We also explore molecular mechanisms which roots have evolved to cope with nutritional, as well as other soil stresses, such as aluminium toxicity and heavy metals. Overall, understanding root dynamics under several environmental variables at different perspectives, from root architecture to biochemistry to genetic levels will allow us to better explore the spatial and temporal relations of roots with their mineral nutrient environment.
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- Date Issued: 2017