Kontopoulou Charis-Konstantina, Liasis Epifanios, Iannetta Pietro Pm, Tampakaki Anastasia, Savvas Dimitrios
Department of Crop Science, Agricultural University of Athens, Iera Odos, Athens, Greece.
The James Hutton Institute, Invergowrie, Dundee, UK.
J Sci Food Agric. 2017 Oct;97(13):4353-4361. doi: 10.1002/jsfa.8202. Epub 2017 Feb 14.
Testing rhizobial inoculation of common bean (Phaseolus vulgaris L.) in hydroponics enables accurate quantification of biological N fixation (BNF) and provides information about the potential of reducing inorganic N fertilizer use. In view of this background, common bean grown on pumice was inoculated with Rhizobium tropici CIAT899 (Rt) and supplied with either full-N (total nitrogen 11.2 mmol L ), 1/3 of full-N or N-free nutrient solution (NS). BNF was quantified at the early pod-filling stage using the N natural abundance method.
Full-N supply to Rt-inoculated plants resulted in markedly smaller nodules than less- or zero-N supply, and no BNF. Rt inoculation of full-N-treated plants did not increase biomass and pod yield compared with non-inoculation. Restriction (1/3 of full-N) or omission of inorganic N resulted in successful nodulation and BNF (54.3 and 49.2 kg N ha , corresponding to 58 and 100% of total plant N content respectively) but suppressed dry shoot biomass from 191.7 (full-N, +Rt) to 107.4 and 43.2 g per plant respectively. Nutrient cation uptake was reduced when inorganic N supply was less or omitted.
Rt inoculation of hydroponic bean provides no advantage when full-N NS is supplied, while 1/3 of full-N or N-free NS suppresses plant biomass and yield, partly because the restricted NO supply impairs cation uptake. © 2017 Society of Chemical Industry.
在水培条件下对普通菜豆（Phaseolus vulgaris L.）进行根瘤菌接种试验，能够准确量化生物固氮（BNF），并提供有关减少无机氮肥使用潜力的信息。鉴于此背景，在浮石上种植的普通菜豆接种了热带根瘤菌CIAT899（Rt），并分别供应全氮（总氮11.2 mmol L）、全氮的1/3或无氮营养液（NS）。在结荚初期使用氮自然丰度法对生物固氮进行量化。
向接种Rt的植株供应全氮导致根瘤明显小于低氮或无氮供应的植株，且无生物固氮。与未接种相比，对全氮处理的植株接种Rt并未增加生物量和荚果产量。限制（全氮的1/3）或不供应无机氮导致成功结瘤和生物固氮（分别为54.3和49.2 kg N ha，分别相当于植株总氮含量的58%和100%），但干茎生物量分别从191.7（全氮，+Rt）降至每株107.4和43.2 g。当无机氮供应减少或不供应时，营养阳离子吸收减少。
当供应全氮营养液时，水培菜豆接种Rt没有优势，而全氮的1/3或无氮营养液会抑制植株生物量和产量，部分原因是有限的硝态氮供应损害了阳离子吸收。© 2017化学工业协会。
