Table 2.
Morphometric characteristics of the studied species and populations of the genus Nivenia
|
N. inaequalis |
N. argentea Aasvoëlkraans |
N. argentea Garcia |
N. binata |
N. corymbosa |
N. fruticosa |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Morph | n | Mean ± s.d. | n | Mean ± s.d. | n | Mean ± s.d. | n | Mean ± s.d. | n | Mean ± s.d. | n | Mean ± s.d. | |
| Floral characteristics (mm) | |||||||||||||
| Stamen height | L | 158 | 35·25 ± 4·74** | 18 | 22·09 ± 1·64 | 166 | 20·91 ± 1·65** | 39 | 13·73 ± 1·62* | 102 | 12·24 ± 1·28** | 54 | 22·51 ± 2·39 |
| S | 138 | 37·28 ± 3·84** | 12 | 21·93 ± 1·18 | 120 | 23·14 ± 1·90** | 15 | 16·05 ± 1·12* | 104 | 19·89 ± 1·84** | |||
| Stigma height | L | 53 | 41·38 ± 2·95** | 6 | 27·19 ± 1·84** | 59 | 25·48 ± 2·02** | 13 | 18·05 ± 1·76** | 35 | 19·46 ± 2·20** | 18 | 27·60 ± 2·87 |
| S | 47 | 30·90 ± 2·80** | 4 | 13·62 ± 1·55** | 41 | 15·41 ± 2·18** | 5 | 12·03 ± 1·60** | 52 | 10·68 ± 1·27** | |||
| Tube diameter | L | 53 | 02·80 ± 0·32 | 6 | 03·34 ± 0·44 | 59 | 03·00 ± 0·45 | 13 | 2·28 ± 0·20 | 35 | 02·51 ± 0·35 | 18 | 02·96 ± 0·58 |
| S | 47 | 02·81 ± 0·33 | 4 | 03·29 ± 0·34 | 41 | 03·03 ± 0·40 | 5 | 2·19 ± 0·23 | 52 | 02·49 ± 0·34 | |||
| Tube length | L | 53 | 33·63 ± 3·31** | 6 | 20·98 ± 1·62* | 59 | 19·94 ± 1·65 | 13 | 10·95 ± 1·41 | 35 | 11·54 ± 1·37** | 18 | 20·75 ± 2·20 |
| S | 47 | 32·28 ± 2·93** | 4 | 17·90 ± 0·98* | 41 | 19·42 ± 1·54 | 5 | 10·31 ± 0·82 | 52 | 12·43 ± 1·51** | |||
| Tepal limb length | L | 53 | 13·40 ± 1·66 | 6 | 11·11 ± 1·03 | 59 | 12·44 ± 1·49* | 13 | 7·59 ± 0·92 | 35 | 09·41 ± 1·25 | 18 | 10·51 ± 1·05 |
| S | 47 | 13·47 ± 1·50 | 4 | 11·28 ± 0·89 | 41 | 11·70 ± 1·64* | 5 | 7·64 ± 0·64 | 52 | 09·17 ± 1·55 | |||
| Bract length | L | 53 | 23·56 ± 2·38 | 6 | 20·76 ± 2·95 | 59 | 20·88 ± 2·17 | 13 | 9·17 ± 0·86 | 35 | 5·41 ± 1·11 | 18 | 13·94 ± 1·04 |
| S | 47 | 22·83 ± 2·85 | 4 | 17·59 ± 3·40 | 41 | 20·02 ± 2·66 | 5 | 9·49 ± 0·86 | 50 | 5·73 ± 0·66 | |||
| Anther length | L | 133 | 01·73 ± 0·24 | 18 | 01·88 ± 0·18** | 164 | 02·22 ± 0·24** | 13 | 1·89 ± 0·18 | 97 | 01·76 ± 0·17** | 54 | 02·19 ± 0·18 |
| S | 65 | 01·80 ± 0·21 | 12 | 02·25 ± 0·20** | 108 | 02·33 ± 0·34** | 5 | 1·95 ± 0·17 | 94 | 01·94 ± 0·20** | |||
| Pollen characteristics in buds [n = number of anthers (number of flowers)] | |||||||||||||
| Total no. of pollen grains per anther | L | 21 (7) | 874·1 ± 184·9 | 15 (5) | 2169·2 ± 322·4 | 21 (7) | 2083·5 ± 209·1 | – | – | 21 (7) | 2236·7 ± 405·5 | 30 (10) | 787·3 ± 246·2 |
| S | 21 (7) | 917·0 ± 228·1 | 12 (4) | 2383·8 ± 275·4 | 21 (7) | 2199·1 ± 360·6 | – | – | 21 (7) | 2295·8 ± 387·3 | |||
| Aborted pollen grains per anther | L | 21 (7) | 12·1 ± 10·1 | 15 (5) | 46·2 ± 44·5 | 21 (7) | 111·8 ± 121·7 | – | – | 21 (7) | 125·5 ± 219·1 | 30 (10) | 142·5 ± 310·5 |
| S | 21 (7) | 20·7 ± 21·5 | 12 (4) | 32·8 ± 15·1 | 21 (7) | 90·1 ± 74·3 | – | – | 21 (7) | 29·2 ± 20·7 | |||
| [n: number of grains (number of flowers)] | |||||||||||||
| Pollen grain size (μm) | L | 525 (7) | 53·35 ± 4·63** | 375 (5) | 45·81 ± 4·77** | 525 (7) | 42·81 ± 4·19** | 225 (7) | 42·77 ± 4·69** | 525 (7) | 39·81 ± 4·00** | 750 (10) | 55·34 ± 7·05 |
| S | 525 (7) | 54·67 ± 4·92** | 300 (4) | 44·25 ± 4·45** | 525 (7) | 46·82 ± 4·39** | 75 (7) | 46·16 ± 3·66** | 525 (7) | 40·75 ± 4·48** | |||
Approach herkogamous flowers were categorized as L, and reverse herkogamous as S. Morphs within populations were compared with a t-test, except that (a) comparisons within the populations of N. binata and N. argentea were performed with non-parametric test (Mann–Whitney) due the small sample size; (b) the number of aborted pollen grains was compared with ANCOVA considering the total number of grains per anther as a co-variable, except for N. binata and N. argentea, where the proportion of aborted pollen grains was compared with non-parametric test (Mann–Whitney).
Values in bold differ significantly between morphs (* P < 0·05, ** P < 0·001).