Table 11.
Effect of varying heat stress on pollen function, stigma and ovular viability in heat-tolerant (T) and heat-sensitive (S) genotypes grown under controlled environment (Mean ± SE).
| Temperature | Pollen viability (%) | Pollen germination (%) | Stigma receptivity (1–5 scale) | Ovule viability (1–5 scale) |
|---|---|---|---|---|
| 25/15°C | ||||
| IG3745 (T) | 78.3 ± 7.8a | 81.2 ± 7.8a | 4.3 ± 0.56a | 4.6 ± 0.37a |
| FLIP2009 (T) | 81.3 ± 8.2a | 76.8 ± 8.2a | 4.6 ± 0.63a | 4.4 ± 0.49a |
| IG2849(S) | 76.9 ± 8.8a | 74.9 ± 8.9a | 4.2 ± 0.67a | 4.4 ± 0.31a |
| IG4242(S) | 82.4 ± 7.5a | 83.5 ± 7.1a | 4.6 ± 0.61a | 4.2 ± 0.49a |
| 35/25°C | ||||
| IG3745(T) | 67.4 ± 8.2b | 60.6 ± 6.8b | 3.9 ± 0.51a | 3.8 ± 0.31b |
| FLIP2009(T) | 72.4 ± 7.6b | 68.6 ± 7.2b | 3.6 ± 0.58a | 3.2 ± 0.43b |
| IG2849(S) | 56.3 ± 5.8bc | 43.4 ± 4.7c | 1.8 ± 0.35c | 1.5 ± 0.38d |
| IG4242(S) | 43.2 ± 4.8c | 39.6 ± 3.8c | 1.4 ± 0.31c | 1.9 ± 0.48d |
| 38/28°C | ||||
| IG3745(T) | 61.5 ± 6.8b | 53.5 ± 5.7b | 2.7 ± 0.16b | 2.8 ± 0.33c |
| FLIP2009(T) | 68.3 ± 7.3b | 58.9 ± 6.4b | 2.9 ± 0.18b | 2.6 ± 0.48c |
| IG2849(S) | 26.6 ± 3.3e | 0 | 0 | 0 |
| IG4242(S) | 18.9 ± 3.1e | 0 | 0 | 0 |
| 40/30°C | ||||
| IG3745(T) | 35.6 ± 2.5cd | 32.4 ± 3.7cd | 1.3 ± 0.15c | 1.4 ± 0.32d |
| FLIP2009(T) | 38.2 ± 2.7cd | 35.6 ± 4.3cd | 1.5 ± 0.17c | 1.5 ± 0.45d |
| IG2849(S) | 0 | 0 | 0 | 0 |
| IG4242(S) | 0 | 0 | 0 | 0 |
| LSD (P < 0.05) (genotypes × treatment Interaction) | 8.2 | 8.9 | 0.67 | 0.57 |
Similar letters in a vertical column indicate no significant difference from each other. LSD, least significant difference.