BORON CONCENTRATION VS. CONTENT AS CRITERION FOR ESTIMATING BORON TOLERANCE IN WHEAT

2013 ◽  
Vol 36 (3) ◽  
pp. 470-480 ◽  
Author(s):  
Milka Brdar-Jokanović ◽  
Ivana Maksimović ◽  
Marija Kraljević-Balalić ◽  
Tijana Zeremski-Škorić ◽  
Ankica Kondić-Špika ◽  
...  
2006 ◽  
Vol 33 (10) ◽  
pp. 973 ◽  
Author(s):  
Sukhjiwan Kaur ◽  
Marc E. Nicolas ◽  
Rebecca Ford ◽  
Robert M. Norton ◽  
Paul W. J. Taylor

Tolerance to high boron concentration in Brassica rapa was primarily due to low net boron uptake by the roots. However, in the two tolerant genotypes, 39–43% of boron uptake was retained in the tap roots, which limited boron accumulation in the leaves, and also contributed to boron tolerance. In the sensitive genotype, 99% of the increase in boron uptake caused by high soil boron accumulated in the leaves, particularly in the leaf margins. Despite higher transpiration rates, lower net boron uptake occurred in the tolerant genotypes. This result cannot be explained by passive boron uptake alone. Active boron efflux was probably responsible for differences in net boron uptake among tolerant and sensitive genotypes. Boron concentration was much lower in the cell walls than in the cell sap of leaves, indicating that storage of boron in the cell walls was not a tolerance mechanism. Despite high boron concentrations in the leaf symplasm, rates of photosynthesis, transpiration and growth were almost unaffected in the tolerant genotypes. The results demonstrate that boron tolerance in Brassica rapa involves boron exclusion at the root level, boron partitioning away from leaves and, as boron accumulates in leaves despite the first two mechanisms, boron tolerance of the leaf tissue itself.


2020 ◽  
Vol 5 (1) ◽  
pp. 18
Author(s):  
Simon Evertz ◽  
Stephan Prünte ◽  
Lena Patterer ◽  
Amalraj Marshal ◽  
Damian M. Holzapfel ◽  
...  

Due to their unique property combination of high strength and toughness, metallic glasses are promising materials for structural applications. As the behaviour of metallic glasses depends on the electronic structure which in turn is defined by chemical composition, we systematically investigate the influence of B concentration on glass transition, topology, magnetism, and bonding for B concentrations x = 2 to 92 at.% in the (Co6.8±3.9Ta)100−xBx system. From an electronic structure and coordination point of view, the B concentration range is divided into three regions: Below 39 ± 5 at.% B, the material is a metallic glass due to the dominance of metallic bonds. Above 69 ± 6 at.%, the presence of an icosahedra-like B network is observed. As the B concentration is increased above 39 ± 5 at.%, the B network evolves while the metallic coordination of the material decreases until the B concentration of 67 ± 5 at.% is reached. Hence, a composite is formed. It is evident that, based on the B concentration, the ratio of metallic bonding to icosahedral bonding in the composite can be controlled. It is proposed that, by tuning the coordination in the composite region, glassy materials with defined plasticity and processability can be designed.


2019 ◽  
Vol 3 (7) ◽  
pp. 211-213
Author(s):  
Yiyang Zhou ◽  
James A. Reindhardt ◽  
Glen E. Martin ◽  
Selene D. Dominguez ◽  
Raymond D. Carey

2004 ◽  
Vol 61 (5) ◽  
pp. 496-500 ◽  
Author(s):  
Anacleto Ranulfo dos Santos ◽  
Waldssimiler Teixeira de Mattos ◽  
Ana Aparecida da Silva Almeida ◽  
Francisco Antonio Monteiro ◽  
Beatriz Dias Corrêa ◽  
...  

Alfalfa cultivar Crioula (Medicago sativa cv. Crioula) is grown in South Brazil and only a few studies on the plants' boron requirement are available. A greenhouse experiment was carried out with alfalfa to measure boron acquisition, production and distribution in the plant; data on critical level and production potentials were recorded. Plants were grown in ground quartz added with 1 L of solution, with the following boron rates: 0, 0.0625, 0.125, 0.25, 0.50, 1.00, and 2.00 mg L-1. Plants were harvested at 46 days of growth. Forage dry mass was increased by boron supply and dry matter accumulation was considerably low in control. Boron concentration in the leaves was higher than in the stems or roots. Boron utilization from the external solution reached 90% at 0.0625 mg L-1 and sharply decreased with further increasing boron rates. Boron concentration and content in the leaves and in plant tops were at maximum when applied boron was between 1.5 and 1.6 mg L-1. Critical levels of boron in plant were 61 mg kg-1 in the leaves and 39 mg kg-1 in plant tops for this cultivar of alfalfa.


2008 ◽  
Vol 92 (8) ◽  
pp. 082109 ◽  
Author(s):  
J. A. Sharp ◽  
A. J. Smith ◽  
R. P. Webb ◽  
K. J. Kirkby ◽  
N. E. B. Cowern ◽  
...  

2017 ◽  
Vol 31 (6) ◽  
pp. 481-485 ◽  
Author(s):  
Tadashi Watabe ◽  
Kohei Hanaoka ◽  
Sadahiro Naka ◽  
Yasukazu Kanai ◽  
Hayato Ikeda ◽  
...  

Author(s):  
Bernardo Arriaza ◽  
David Blumenstiel ◽  
Dulasiri Amarasiriwardena ◽  
Vivien G. Standen ◽  
Arnoldo Vizcarra

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