Zinc deficiency-induced phytosiderophore release by the Triticaceae is not consistently expressed in solution culture

Abstract

The effects of zinc (Zn) and iron (Fe) deficiencies on phytosiderophore (PS) exudation by three barley (Hordeum vulgare L.) cultivars differing in Zn efficiency were assessed using chelator-buffered nutrient solutions. A similar study was carried out with four wheat (Triticum aestivum L. and T. durum Desf.) cultivars, including the Zn-efficient Aroona and Zn-inefficient Durati. Despite severe Zn deficiency, none of the barley or wheat cultivars studied exhibited significantly elevated PS release rates, although there was significantly enhanced PS exudation under Fe deficiency. Aroona and Durati wheats were grown in a further study of the effects of phosphate (P) supply on PS release, using 100 microM KH2PO4 as high P, or solid hydroxyapatite as a supply of low-release P. Phytosiderophore exudation was not increased due to P treatment under control or Zn-deficient conditions, but was increased by Fe deficiency. Accumulation of P in shoots of Zn- and Fe-deficient plants was seen in both P treatments, somewhat more so under the KH2PO4 treatment. Zinc-efficient wheats and grasses have been previously shown to exude more PS under Zn deficiency than Zn-inefficient genotypes. We did not observe Zn-deficiency-induced PS release and were unable to replicate the results of previous researchers. The tendency for Zn deficiency to induce PS release seems to be method dependent, and we suggest that all reported instances may be explained by an induced physiological deficiency of Fe.

Evidence for the Root-Uptake of Arsenite at Lateral Root Junctions and Root Apices in Rice (Oryza sativa L.)

“…Plants were grown in a chelator-buffered nutrient solution consisting of macro-and micronutrients detailed in Table 1 and exposed to As concentrations of 6.7 µM As(III) i for six weeks. The nutrient solution was buffered with 2-(N-morpholino)ethanesulfonic acid (MES) adjusted to a pH of 6.5, and contained 57.7 µM HEDTA (2-hydroxyethyl)ethylenediaminetriacetic acid), which is a 27.7 molar excess of the sum of micronutrients [42,43]. Nutrient solutions were changed every 3-5 days, with more frequent changes as the plants grew larger.…”

Foliar Applied Potassium and Zinc Enhances Growth and Yield Performance of Maize under Rainfed Conditions

“…Potassium fertilization either applied on foliage or soil, cope the drought stress and consequently decreases the transpiration rate of crop plants (Zareian et al, 2013). Pedler et al (2000) resulted that zinc application increases the CGR and might be due to the role of zinc in bio-synthesis of tryptophan, a precursor of auxin hormone and mainly responsible for rapid growth rate. Application of potassium and zinc fertilizers either on soil or foliage showed that NAR had a positive linear relationship with potassium fertilizers (Szewczuk et al, 2009;Nadim et al, 2012).…”

Effect of Foliar Application of Some Nutrients on "Le-Conte" Pear Trees Grown under Calcareous Soil Conditions

“…In fact, zinc is essential for tryptophan synthesis, which is a prerequisite for auxin formation, therefore amount of auxin decreases by zinc deficiency (Marschner, 1995 andPedler et al, 2000). Zinc is the main building part of some enzymes and is needed for the plant enzymes formation of most species.…”

“…Zinc is the main building part of some enzymes and is needed for the plant enzymes formation of most species. In addition, many enzymatic reactions be active by zinc (Vitosh et al, 1994, Pedler et al, 2000and Akay, 2011. Table 4 demonstrate the effect of conducted treatments on the pear tree yield (Kg.).…”