Water table depth affects Populus alba fine root growth and whole plant biomass

Abstract

Summary 1.To increase understanding of the water table's influence on both fine-root growth and wholeplant growth of tree species in arid and semi-arid regions, we exposed Populus alba L. cuttings to contrasting soil water conditions via various water table gradients. 2. One-year-old rooted cuttings were grown individually in pots containing sandy soil in a greenhouse for 90 days in four water-table depth treatments: constant depth at 45 cm from the soil surface, constant depth at 30 cm, constant depth at 15 cm, and fluctuating depths between 45 and 30 cm. Growth responses, biomass partitioning, and structure and morphology of leaves and roots were determined for harvested trees every 30 days. 3. Fine (< 1-mm diameter) root growth was affected by water-table levels and water profiles, even in the fluctuating water-table depth treatment. Fine root proliferation was inhibited below the water table and was stimulated in the layers just above the water table and near the soil surface. 4. At the whole-plant level, with deeper water tables, P. alba allocated more biomass to roots and root morphology changed, but total root length did not increase, suggesting that trees faced with soil water deficits are not likely to increase root surface area to obtain more water. 5. Total biomass and root length in each treatment were positively correlated and the relationships were similar among the treatments, although the growth responses varied under the various watertable conditions. These results suggest that variation in root length may have an important effect on the biomass of the rooted cuttings across a gradient of water-table depths.

Corn root morphoanatomy at different development stages and yield under water stress

“…In some crops, such as rice (Anantha et al, 2016), sorghum (Magalhães et al, 2016) and corn (Grieder et al, 2014), a more developed and deeper root system contributes substantially to improve performance under water stress. However, according to Imada et al (2008), root surface area is more related to the absorption of nutrients.…”

Patterns of biomass allocation in Haloxylon persicum woodlands and their understory herbaceous layer along a groundwater depth gradient

“…Dryland is also one of the most sensitive area to climate change and human activities (Huang et al, 2016). Because of low rainfall and high evapotranspiration in this region, groundwater is often an important water source for perennial plants (Imada et al, 2008;Cui and Shao, 2005;Naumburg et al, 2005). The dynamics and the availability of the groundwater plays an important role in defining vegetation composition and distribution (Elmore et al, 2006;Naumburg et al, 2005), and in driving the vegetation dynamic and shifting the interactive balance between wooden species and herbaceous plants (McCluney et al, 2012;Cooper et al, 2006;Holzapfel et al, 2006).…”

“…The effect of water table depth on above/below ground biomass allocation in desert plant communities have been studied on small scales: with natural variations in water tables across microtopographies (e.g., hummocks and hollows) (Vasander, 1982;Håland and Braekke, 1989;Moore et al, 2002;Murphy et al, 2009a;Murphy et al, 2009b;Murphy and Moore, 2010), or in response to water table manipulations (Vasander, 1982;Braekke, 1992;Laiho and Finér, 1996;Finér and Laine, 2000;Weltzin et al, 2000;Imada et al, 2008;Breeuwer et al, 2009). Few studies are available on the shifts in above-and belowground allocation patterns among plant functional groups in response to natural water table gradients.…”

Early evaluation of root morphology of maize genotypes under phosphorus deficiency

“…The greater root growth, mainly of thin roots and very thin roots, as noted in the strain L 13.1.2, may be connected to this root exploitation in the search of greater acquisition of phosphorus. Imada et al (2008) say that the root surface area is more related to the nutrients absorption. A larger surface area was noted in the strain L 13.1.2, which can help the plant to obtain Average followed by the same low case letter in the columns for the genotypes and capital letters in the lines for the conditions (HP and LP), do not differ by the Scott-Knott test at 5% probability (P ≤ 0.05).…”