Root morphological traits related to phosphorus - uptake efficiency of soybean, sunflower, and maize
Many of the plant acquisition strategies for immobile nutrients, such as phosphorus [P], are related to the maximization of soil exploration at minimum metabolic cost. Previous studies have suggested that soybean [Glycine max L.], sunflower [Helianthus annuus L.], and maize [Zea mays L.] differ in their P uptake efficiency. In this investigation we employed these three species to evaluate: [1] the effect of suboptimal P conditions on root morphological traits related to root porosity and fineness and [2] how these traits are related to P-uptake efficiency. Opaque 25-L plastic containers were used to grow plants hydroponically. The three species were compared under two P availability levels [low P and high P]. Most of the observed responses were in the direction to favor P uptake under low-P conditions. Compared to P-sufficient plants, P-stressed plants of the three species showed higher root-to-shoot ratio, specific root length, root porosity and root aerenchyma, and a lower root density. For example, P-stress increased root porosity by a factor of 2.0, 1.4, and 1.4 in soybean, sunflower, and maize, respectively. Soybean and sunflower were the species with the highest P-uptake efficiency, expressed as P uptake either per unit root biomass or length. The results demonstrate the central role of aerenchyma development in modifying root length per unit root biomass and, thus, reducing the root`s foraging costs. Consequently, aerenchyma is suggested to be a possible mechanism for better P-uptake efficiency.
| Main Authors: | , |
|---|---|
| Format: | Texto biblioteca |
| Language: | eng |
| Subjects: | AERENCHYMA, MINERAL NUTRITION, PLANT STRESS, ROOT MORPHOLOGY, , |
| Online Access: | http://ceiba.agro.uba.ar/cgi-bin/koha/opac-detail.pl?biblionumber=47297 http://ceiba.agro.uba.ar/cgi-bin/koha/opac-detail.pl?biblionumber= |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Many of the plant acquisition strategies for immobile nutrients, such as phosphorus [P], are related to the maximization of soil exploration at minimum metabolic cost. Previous studies have suggested that soybean [Glycine max L.], sunflower [Helianthus annuus L.], and maize [Zea mays L.] differ in their P uptake efficiency. In this investigation we employed these three species to evaluate: [1] the effect of suboptimal P conditions on root morphological traits related to root porosity and fineness and [2] how these traits are related to P-uptake efficiency. Opaque 25-L plastic containers were used to grow plants hydroponically. The three species were compared under two P availability levels [low P and high P]. Most of the observed responses were in the direction to favor P uptake under low-P conditions. Compared to P-sufficient plants, P-stressed plants of the three species showed higher root-to-shoot ratio, specific root length, root porosity and root aerenchyma, and a lower root density. For example, P-stress increased root porosity by a factor of 2.0, 1.4, and 1.4 in soybean, sunflower, and maize, respectively. Soybean and sunflower were the species with the highest P-uptake efficiency, expressed as P uptake either per unit root biomass or length. The results demonstrate the central role of aerenchyma development in modifying root length per unit root biomass and, thus, reducing the root`s foraging costs. Consequently, aerenchyma is suggested to be a possible mechanism for better P-uptake efficiency. |
|---|