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Determining the Impact of the AM-Mycorrhizosphere on “Dwarf” Sunflower Zn Uptake and Soil-Zn Bioavailability  [PDF]
Patrick Audet,Christiane Charest
Journal of Botany , 2010, DOI: 10.1155/2010/268540
Abstract: An in vivo compartmental pot greenhouse experiment involving “dwarf” sunflower and an arbuscular mycorrhizal (AM) fungus was designed to assess the contribution of non-AM roots (rhizosphere), AM roots and extraradical hyphae (mycorrhizosphere), or strictly extraradical hyphae (hyphosphere) on plant growth, plant metal uptake, and soil parameters using the micronutrient zinc (Zn) as a typical metal contaminant. We observed that, at high soil-Zn concentrations, the mycorrhizosphere treatments had lower Zn concentrations (especially in shoots and flowers) and a lower incidence of leaf chlorosis than the rhizosphere treatments. These phytoprotective effects are believed to be related to AM-induced biosorption processes that reduce soil metal bioavailability to delay the onset of plant metal toxicity. We also observed that the presence of extraradical hyphae causes a slight alkalinisation of the proximal soil environment whereas roots tended to acidify it, this having significant consequences toward metal bioavailability. Altogether, the AM symbiosis is considered to be a key component of ecosystem function involved in buffering plant growth conditions due to the processes of metal biosorption and hyphal alkalinisation which could contribute in enhancing the soil's resiliency. 1. Introduction The arbuscular mycorrhizal (AM) symbiosis—a mutually beneficial association between the roots of most herbaceous plants and Glomeromycotan fungi [1]—is primarily recognized for increasing the mineral status of plants via the mycorrhizosphere (i.e., combined surface area of AM roots and extraradical hyphae). It has also been suggested that the mycorrhizosphere plays a key role in the regulation of soil metal bioavailability through biosorption processes, then contributing to the alleviation of plant metal toxicity and nutrient imbalances [2–6]. Recently, we proposed a conceptual model derived from meta-analytical findings depicting the impact of the AM symbiosis on plant metal uptake in relation to soil conditions ranging from low (trace) to high (toxic) metal exposure levels [7–9], a model we further investigated using an in vitro carrot root-organ culture system [10]. From these studies, we demonstrated that the AM fungi play a dual role in metal acquisition: first by increasing nutrient uptake at low metal exposure levels, and then lessening it at high levels through metal biosorption. Notably, in our in vitro study [10], we suggested that the “enhanced uptake” and “metal biosorption” processes occur independently in shaping plant metal uptake and, also, likely hold
Effects of Foliar Micronutrient Application on Osmotic Adjustments, Grain Yield and Yield Components in Sunflower (Alster cultivar) under Water Stress at Three Stages  [cached]
M Babaeian,M Haydari,A Ghanbari
Journal of Science and Technology of Agriculture and Natural Resources , 2009,
Abstract: In order to study the effects of foliar micronutrient application under water stress at three stages of growth on proline and carbohydrate concentrations, grain yield and yield components of sunflower (Alster cultivar), a field experiment in split plot design with three replications was conducted in 2007. Alster cultivar was considered under water stress at three stages of growth (heading, flowering and grain filling) as main plot and seven micronutrient treatments, Fe, Zn, Mn, Fe+Zn, Fe+Mn, Zn+Mn and Fe+Zn+Mn, as sub plots. Results showed, water stress at three stages of growth significantly decreased grain yield, biological yield, 1000 weight seeds, cap diameter and cap weight of sunflower (Alster cultivar). The impact of water stress was more pronounced when applied at grain filling. Use of foliar micronutrient increased grain yield in water stress. On the other hand, use of Mn foliar application had the highest positive effect on yield components and grain yield. Free proline and total soluble carbohydrate concentration were increased under water stress at all of the three stages of growth. The highest concentration of these two components was found on the flowering stage. Foliar micronutrient also increased accumulation of the two components.
Effect of Sulphur Fertilizer on Yield and Nutrient Uptake of Sunflower Crop in an Albaquept Soil
Shamima Nasreen,S. M. Imamul Huq
Pakistan Journal of Biological Sciences , 2002,
Abstract: Yield and uptake of N, P, K and S at successive stages of growth in sunflower (cv. Kironi) were studied at 0, 20, 40, 60, 80, 100 and 120 kg S ha -1 grown in a typical Albaquept soil in field over a period of three years (1995-96, 1996-97 and 1997-98). Sulpher had synergistic effect on the yield and nutrients uptake. Application of sulphur between 60-80 kg ha -1 increased significantly the seed yield and uptake of N, P, K and S. Head accumulated the highest nutrients followed by stem and leaf. Higher dose of sulphur tended to decrease the yield and nutrient uptake in all the years. Plants grown without added S had lowest yield and nutrients uptake. Considering the sulphur cost, 60 kg S ha -1 would be required in this soil type to exploit the satisfactory yield of sunflower.
Effect of Microbial Inoculants on Uptake of Nutrient Elements in Two Cultivars of Sunflower (Helianthus annuus L.) in Saline Soils  [cached]
Mostafa SHIRMARDI,Gholam Reza SAVAGHEBI,Kazem KHAVAZI,Ali AKBARZADEH
Notulae Scientia Biologicae , 2010,
Abstract: A greenhouse experiment was conducted in order to evaluate the interactive effects of microbial inoculants on uptake of nutrient elements (N, P, K, Ca, Mg, Na, Cl, Fe, Zn, Cu, Mn) in two cultivars of sunflower. The trials were carried out on saline (EC = 7.6 dS m-1) calcareous soils taken from Eshtehard (Karaj) region of Iran. In a factorial trial and completely randomized design (CRD), three levels of arbuscular mycorrhizal inoculants (non inoculation, inoculation withGlomus etunicatum and Glomus intradices) and four levels of Pseudomonas fluorescensinoculants (non inoculation and inoculation with Pseudomonas fluorescens strains 4, 9, 12) in two cultivars of sunflower with four replications per treatments were applied. Results revealed that all of the treatments increased the N uptake in Euroflor cultivar. Moreover, in Euroflor cultivar, inoculation with Pseudomonas fluorescens strains 9 and co-inoculation of Pseudomonas fluorescens strains 4 and Glomus intradices made a significant different in phosphorous uptake, while did not make any significant change in the Master cultivar. However, bacterial and fungal treatments significantly (P < 0.05) increased uptake of micro nutrients such as Fe, Zn and Mn.
Effects of salinity and Cu on total uptake of micronutrient in shoot and root of pistachio cultivars (Pistacia vera L.)  [cached]
S. Eskandari,V. Mozaffari
Journal of Science and Technology of Greenhouse Culture , 2013,
Abstract: To study the effects of soil Cu and salinity levels on uptake of micronutrients by shoots and roots of pistachio seedlings, a factorial experiment was carried out as completely randomized design with three replications in greenhouse of College of Agriculture, Vali-e-Asr University of Rafsanjan, Iran, in May 2008. Treatments consisted of five salinity levels (0, 800, 1600, 2400 and 3200 mg NaCl per kg soil), four Cu levels (0, 2.5, 5 and 7.5 mg Cu per kg soil) and two pistachio cultivars (Badami Zarand and Ghazvini). Results showed that salinity stress significantly (P<0.05) decreased the uptake of micronutrients including Cu, Fe, Zn and Mn by shoots and roots. Application of 5 mg Cu per kg soil significantly increased the uptake of Cu, Fe and Mn by shoots, but had no significant effect on Zn uptake by shoots. Application of 2.5 mg Cu per kg soil significantly increased uptake of Cu, Fe and Mn by roots, while had no significant effect on Zn uptake by roots. In conclusion, the uptake of micronutrients in Badami Zarand cultivar was significantly higher than Ghazvini cultivar. Since trees suffer from deficiency of micronutrients in pistachio orchards, using Badami Zarand cultivar is recommended as pistachio rootstock.
Micronutrient Fertilizers
Syed Manzoor Alam,Saboohi Raza
Pakistan Journal of Biological Sciences , 2001,
Abstract: This paper deals with the importance of different micronutrient fertilizers regarding the growth and development of plants. There are a few micronutrients, which are very essential for the growth of plants. A shortage of these nutrients will create deficiency symptoms in plants, which ultimately reduce their growth.
Oxygen uptake during the exercise: temporal aspectos and adjustments of curves
Adriano Eduardo Lima Silva,Fernando Roberto de Oliveira
Revista Brasileira de Cineantropometria e Desempenho Humano , 2004,
Abstract: The oxygen uptake has been considered as one of the most important physiological variables for exercise physiology. The first models relating oxygen uptake with performance emerged in the beginning of last century and it has been intensely discussed in the literature until today. This review discussed some topics about oxygen uptake, more specifically on aspects related with the kinetic and influences of the time response of this variable on the adjustment curve during an incremental test. Discussion on the level of aerobic condition and exercise intensity on the kinetics of oxygen uptake are also included in the text. Finally, verification on the slow component and on the physiological control of the oxygen uptake kinetics is also presented. RESUMO O consumo de oxigênio tem sido considerado uma das variáveis fisiológicas mais importantes para a fisiologia do exercício. Os primeiros modelos relacionando o consumo de oxigênio com o desempenho esportivo surgiram no inicio do século passado e continua sendo intensamente discutido na literatura atual. A presenterevis o discutiu alguns tópicos sobre consumo de oxigênio, mais especificamente sobre aspectos relacionados à cinética e a influencia do tempo de resposta dessa variável sobre os ajustes de curva em teste progressivo. Discuss es relacionadas a influencia do nível de aptid o aeróbia e a intensidade do exercício sobre a cinética do consumo de oxigênio também est o inseridas no texto. Por fim, algumas constata es sobre componente lento e os controles fisiológicos da cinética do consumo de oxigênio s o abordados.
Influence of Bradyrhizobium japonicum and Phosphorus on Micronutrient Uptake in Cowpea. A Case Study of Zinc (Zn), Iron (Fe), Copper (Cu) and Manganese (Mn)  [PDF]
Daniel Nyoki, Patrick A. Ndakidemi
American Journal of Plant Sciences (AJPS) , 2014, DOI: 10.4236/ajps.2014.54056
Abstract:


The field and screen house experiments were carried out in the 2013 cropping season to assess the effects of B. japonicum inoculation and phosphorus supplementation on the uptake of micronutrients in the cowpea. The experiment was laid out in a split plot design where the main plots comprised two inoculation treatments (with and without B. japonicum inoculation) and sub plots included four different levels of phosphorus (0, 20, 40, and 80 kg P/ha). The results showed a significant improvement in the uptake of micronutrients in the B. japonicum inoculated treatments over the control. Phosphorus supplementation (40 kg P/ha) also showed a significant increase in the uptake of some micronutrients while decreasing the uptake of Zn in some plant organs. There was also a significant interaction between B. japonicum inoculation and phosphorus in the root uptake of Zn for the field experiment.


Micronutrient application through seed treatments: a review
Farooq,M; Wahid,A; Siddique,Kadambot H. M;
Journal of soil science and plant nutrition , 2012, DOI: 10.4067/S0718-95162012000100011
Abstract: micronutrients are vital for plant growth and human health. soil and foliar applications are the most prevalent methods of micronutrient addition but the cost involved and difficulty in obtaining high quality micronutrient fertilizers are major concerns with these in developing countries. micronutrient seed treatments, which include seed priming and seed coating, are an attractive and easy alternative. here in this review, we discuss the potential of micronutrient seed treatments for improving crop growth and grain nutrient enrichment. micronutrient application through seed treatments improves the stand establishment, advances phenological events, and increases yield and micronutrient grain contents in most cases. in some instances, seed treatments are not beneficial; however, the negative effects are rare. in most cases, micronutrient application through seed treatment performed better or similar to other application methods. being an easy and cost effective method of micronutrient application, seed treatments offer an attractive option for resource-poor farmers.
Micronutrient application through seed treatments: a review  [cached]
M Farooq,A Wahid,Kadambot H. M Siddique
Journal of Soil Science and Plant Nutrition , 2012,
Abstract: Micronutrients are vital for plant growth and human health. Soil and foliar applications are the most prevalent methods of micronutrient addition but the cost involved and difficulty in obtaining high quality micronutrient fertilizers are major concerns with these in developing countries. Micronutrient seed treatments, which include seed priming and seed coating, are an attractive and easy alternative. Here in this review, we discuss the potential of micronutrient seed treatments for improving crop growth and grain nutrient enrichment. Micronutrient application through seed treatments improves the stand establishment, advances phenological events, and increases yield and micronutrient grain contents in most cases. In some instances, seed treatments are not beneficial; however, the negative effects are rare. In most cases, micronutrient application through seed treatment performed better or similar to other application methods. Being an easy and cost effective method of micronutrient application, seed treatments offer an attractive option for resource-poor farmers.
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