Table I.
Comparative UV absorbance of fractions with molecular mass ≤10 kD of Ni-S and Ni-D foliage from young pecan seedling trees
| Sample
|
Dilutiona
|
Absorbance
|
|
|---|---|---|---|
| 190 nm | 220 nm | ||
| Ni-D | 100 | 3.45 | 3.85 |
| Ni-S | 100 | 3.45 | 2.50 |
a
Each time 0.8 g (fresh weight) of young pecan leaves was dipped into 2 mL of HPLC-grade water and then homogenized and centrifuged. A total of 2 mL of sample solutions was prepared after filtering with a 10-kD filter to remove large molecules. These sample solutions (molecular mass ≤10 kD) were further diluted 100-fold for UV spectrum scanning.