Table 1.
Filament length and distances as number of vegetative cells of the two polar heterocysts of Cylindrospermum sp. In the presence of chemical fertilizers in an N2-fixing mediuma.
| Chemical fertilizers (ppm) | Filament length (µm) | Number of vegetative cells in a filament |
|---|---|---|
| Control | 47.8 ± 8.7 | 16.3 |
| Urea (10) | 58.5 ± 7.3 | 22.4 |
| Urea (50) | 59.7 ± 8.8 | 22.4 |
| Superphosphate (10) | 51.3 ± 6.7 | 18.1 |
| Superphosphate (50) | 52.1 ± 7.5 | 17.3 |
| Potash (100) | 52.8 ± 6.5 | 17.6 |
| Potash (200) | 53.0 ± 7.0 | 18.8 |
a
Each value is an average of 10 observations. From values of filament length and numbers of vegetative cells in filament from control and fertilizer treated cultures, Pearsonian r (correlation coefficient) computed was 0.9237, a value less than 0.95. Computation of heterocyst percentage in terminal heterocystous filaments such as of Cylindrospermum becomes ambiguous, so it was not done.