Comparison of glycine uptake by pak choi in organic and conventional soil under different glycine concentrations: A pot study

Abstract

Many studies have shown that plants can utilize organic N in the form of amino acids. However, it is unclear whether the glycine-uptake capability responds differently to various farm management systems, and whether the interaction of farm management type with soil glycine concentrations affects the glycine uptake by plants. A pot experiment was conducted in which pak choi (Brassica campestris ssp. chinensis Makino var. communis Tsen et Lee) was grown in soil from organic and conventional agricultural systems for 15 d prior to labeling with 2-13 C, 15 N-glycine in a range of Gly concentrations (0, 0.005, 0.05, 0.5, 5, and 15 μg N g -1 dry soil). The glycine uptake rate increased with increasing applied N concentrations, whereas the glycine recovery increased initially and then decreased. Regardless of glycine concentration, the glycine uptake rates of whole plants were moderate, but not significantly higher in organic than in conventional soil. The plant glycine recovery in organic soil was significantly higher than in conventional soil. Therefore, we suggest that pak choi glycine uptake differs under organic and conventional management systems. More research efforts should focus on the nutritional function of organic N in organic systems.

Exogenous glycine inhibits root elongation and reduces nitrate-N uptake in pak choi (Brassica campestris ssp. Chinensis L.)

“…Plants are able to take up amino acids as a source of N [ 3 , 52 ], and we confirmed Gly was absorbed by pak choi seedlings (Figs 3 , 4 and 6 ). For pak choi grown in mixtures of Gly and NO 3 - -N, 15 N-Gly uptake accounted for 28.2–35.7% of shoot N and 53.3–61.7% of root N ( Fig 3B and 3D ).…”

“…NO 3 - -N has been traditionally viewed as the main form of inorganic N taken up by plants. However, an increasing number of studies have shown that organic N also contributes to plant N nutrition [ 3 – 7 ]. Amino acids are ubiquitously found in the soil solution and may represent a significant source of N for plants in terrestrial ecosystems.…”

Effects of different nitrogen forms and concentration combinations on American ginseng seedling growth

“…Owing to advances in technology, it has been revealed that plants cannot only absorb inorganic N but also a certain amount of small molecule organic-N (Wang et al, 2015). Inorganic N sources include nitrate, ammonium, amino acids, small molecular-weight peptides, and proteins, all of which are important N sources provided by fertilizers (Gioseffi et al, 2011;Paungfoo-Lonhienne et al, 2012).…”