Analysis of edible characteristics, antioxidant capacities, and phenolic pigment monomers in Lilium bulbs native to China.

Lilium is cherished for its health-promoting properties in China. The bulbs of Lilium are rich in phenolic compounds, which are associated with antioxidant capacity. However, no systematic evaluation on phenolic compositions and antioxidant capacities for the edible Lilium native to China has been conducted. Herein, bulbs of 56 wild populations and three cultivars were collected. Their edible characteristics, antioxidant capacities, and pigments have been investigated and analyzed. The results showed that phenolic compounds contributed to the major colors (red, yellow and white) in Lilium bulbs. The seven phenolic pigment monomers responsible for the color of bulbs-cyanidin-3-O-rutinoside, isoquercitrin, regaloside B, regaloside C, regaloside H, regaloside A and regaloside D-were identified by the combination of HPLC-MS and NMR analysis. The population Lilium regale E. H. Wilson (Maoxian County, Sichuan Province) had the highest antioxidant capacity. According to the quantification results, Lilium bulbs with darker and redder colors possessed larger biomass, better nutrient compositions, significantly higher bioactive constituents, and higher antioxidant capacities than the three currently consumed cultivars of edible lily bulbs. Overall, these findings suggest that the mountainous area of southwest China could be the fourth source of edible lilies with the bulb-colored Lilium species.

[Nitrogen uptake, distribution, and utilization in young bearing Huangguan pear trees under 15N-urea application in spring].

We investigated the characteristics of nitrogen uptake, distribution, and utilization in the three-year-old bearing Huangguan pear trees following 15N-urea application in early spring. The results showed that the growth of pear trees was mainly depended on vegetative organs such as shoots and leaves at the stage from budbreak to shoot growth arrest, but mainly on storage organs (roots) and supplemented by the formation of fruit yield and quality at the stage from shoot growth arrest stage to fruit harvest. Meanwhile, tree biomass, especially that storage organs, substantially increased. All organs, especially newly developed shoots and leaves, acquired more N in shoot growth arrest stage due to vigorous growth, with relatively higher N derived from fertilizer (Ndff). Ndff of each organ except for root was lower at fruit maturity stage than that at shoot growth stage. Most of the labeled nitrogen was distributed in the newly developed organs (shoots and leaves) from budbreak to shoot growth arrest stage, but in the storage organs during shoot growth arrest stage to fruit maturity stage. Labeled fertilizer nitrogen was mainly distributed in the storage organs, followed by the vegetative organs. Reproductive organs had the lowest allocation in the experimental stage. For the three-years-old pear trees, the ratio of absorbed N from fertilizer was responsible for 31.1% and 21.0% of total absorbed nitrogen from budbreak to shoot growth arrest stage and from shoot growth arrest stage to fruit maturity stage, respectively, with the remaining N (68.9% and 79.0% of total) being absorbed from soil N.