caa a22 4500 477112374 CHVBK 20180405111613.0 cr unu---uuuuu 170330e19960901xx s 000 0 eng 10.1007/BF00011434 doi (NATIONALLICENCE)springer-10.1007/BF00011434 The importance of sampling immature leaves for the diagnosis of boron deficiency in oilseed rape ( Brassica napus cv. Eureka) [Elektronische Daten] [Longbin Huang, Zhengqian Ye, Richard Bell] Plant analysis can diagnose boron (B) deficiency when the standards used have been properly developed by establishing that a close relationship exists between B concentration in a plant part and its physiological function. The purpose of the present study was to demonstrate the importance of choosing the growing immature leaves for B deficiency diagnosis and for establishing critical B concentrations for the diagnosis of B deficiency in oilseed rape (Brassica napus). In Experiment 1, the plants were subject to seven levels of B supply using programmed nutrient addition, for the estimation of critical B concentrations in plant parts for shoot growth. In Experiment 2, the plants were treated with two levels of B supply in solution: 10 (+B) and 0 (-B) μM B, for the estimation of functional B requirements for leaf elongation. The results showed that critical B concentrations varied amongst the plant parts sampled and decreased with leaf age. As B taken up by roots is largely phloem-immobile, B concentrations in mature leaves are physiologically irrelevant to plant B status at the time of sampling, giving rise to a significant over- or underestimation of the B requirement for plant growth. By contrast, a growing, immature leaf, in this case the youngest open leaf (YOL), was the most reliable plant part for B deficiency diagnosis. Critical B concentrations developed from both methods were comparable-i.e. 10-14 mg B kg−1 dry matter in the YOL at vegetative growth stages up to stem elongation. Kluwer Academic Publishers, 1996 B deficiency diagnosis nationallicence boron (B) nationallicence Brassica napus nationallicence critical B concentration nationallicence functional B requirement nationallicence leaf elongation nationallicence oilseed rape nationallicence shoot growth nationallicence Huang Longbin School of Biological and Environmental Sciences, Murdoch University, 6150, Murdoch, W.A., Australia aut Ye Zhengqian School of Biological and Environmental Sciences, Murdoch University, 6150, Murdoch, W.A., Australia aut Bell Richard School of Biological and Environmental Sciences, Murdoch University, 6150, Murdoch, W.A., Australia aut Plant and Soil Kluwer Academic Publishers; http://www.wkap.nl 183/2(1996-09-01), 187-198 0032-079X 183:2<187 1996 183 11104 https://doi.org/10.1007/BF00011434 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00011434 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Huang Longbin School of Biological and Environmental Sciences, Murdoch University, 6150, Murdoch, W.A., Australia aut NATIONALLICENCE 700 1- Ye Zhengqian School of Biological and Environmental Sciences, Murdoch University, 6150, Murdoch, W.A., Australia aut NATIONALLICENCE 700 1- Bell Richard School of Biological and Environmental Sciences, Murdoch University, 6150, Murdoch, W.A., Australia aut NATIONALLICENCE 773 0- Plant and Soil Kluwer Academic Publishers; http://www.wkap.nl 183/2(1996-09-01), 187-198 0032-079X 183:2<187 1996 183 11104 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer