TABLE 5.
Impact of plant growth regulators on hormones content in xylem sap of rice under heat stress at heading stage.
| Tem | PGR | TZ9G |
ZR |
DIHZR |
DIZ |
Z |
IPMP |
IP9G |
IPA |
IP |
|||||||||
| (pg ml–1 XS) | |||||||||||||||||||
| IR-64 | HHZ | IR-64 | HHZ | IR-64 | HHZ | IR-64 | HHZ | IR-64 | HHZ | IR-64 | HHZ | IR-64 | HHZ | IR-64 | HHZ | IR-64 | HHZ | ||
| HNT | Vc + Ve + MeJA + Br | 664.3 | 717.9 | 522.5 | 724.5 | 24.4 | 37.4 | 13.0 | 23.2 | 218.5 | 297.2 | 43.9 | 58.1 | 36.8 | 52.0 | 59.5 | 93.0 | 21.6 | 29.6 |
| Br + Tr + MeJA | 683.0 | 737.6 | 518.7 | 718.5 | 18.5 | 30.8 | 11.0 | 21.2 | 210.1 | 291.5 | 39.3 | 51.6 | 42.0 | 56.0 | 52.3 | 82.4 | 19.1 | 26.8 | |
| VC + Ve | 705.2 | 757.3 | 514.4 | 711.1 | 10.2 | 25.7 | 8.6 | 18.1 | 200.9 | 287.3 | 30.9 | 46.5 | 48.6 | 60.6 | 43.8 | 73.3 | 16.0 | 23.9 | |
| MeJA | 723.8 | 774.9 | 505.9 | 704.7 | 6.0 | 22.3 | 7.2 | 15.6 | 192.3 | 282.3 | 26.8 | 43.0 | 54.5 | 66.6 | 35.7 | 65.3 | 11.9 | 20.5 | |
| AC | 738.5 | 794.0 | 501.3 | 698.4 | 5.6 | 19.2 | 6.7 | 13.6 | 184.5 | 278.8 | 23.4 | 40.0 | 59.8 | 72.2 | 28.9 | 58.6 | 6.8 | 17.7 | |
| HDT | Vc + Ve + MeJA + Br | 602.6 | 693.4 | 543.9 | 735.1 | 34.3 | 48.0 | 21.1 | 28.9 | 230.7 | 315.3 | 55.1 | 68.7 | 30.6 | 46.8 | 79.6 | 107.9 | 25.6 | 31.5 |
| Br + Tr + MeJA | 615.4 | 707.9 | 537.7 | 729.0 | 29.5 | 42.0 | 19.3 | 27.0 | 223.5 | 309.2 | 50.2 | 62.7 | 34.7 | 51.1 | 72.3 | 99.5 | 22.2 | 29.1 | |
| VC + Ve | 634.0 | 725.5 | 530.3 | 719.1 | 21.7 | 36.6 | 15.8 | 23.6 | 219.0 | 302.9 | 42.4 | 57.4 | 39.8 | 56.7 | 65.6 | 88.3 | 19.3 | 26.7 | |
| MeJA | 650.8 | 740.2 | 522.8 | 712.9 | 15.3 | 31.6 | 12.4 | 20.4 | 212.7 | 293.4 | 36.0 | 52.4 | 44.2 | 62.6 | 54.7 | 78.1 | 15.8 | 23.7 | |
| AC | 672.4 | 755.5 | 517.5 | 706.6 | 11.2 | 28.0 | 9.9 | 18.6 | 205.0 | 286.5 | 32.0 | 48.8 | 49.9 | 66.1 | 44.7 | 68.6 | 12.7 | 21.6 | |
| AT | Vc + Ve + MeJA + Br | 540.9 | 656.6 | 558.2 | 740.9 | 43.9 | 53.2 | 25.8 | 30.8 | 244.3 | 323.2 | 64.7 | 74.0 | 26.1 | 43.0 | 93.1 | 114.0 | 34.3 | 34.4 |
| Br + Tr + MeJA | 552.3 | 666.1 | 555.7 | 736.2 | 41.1 | 48.7 | 24.0 | 29.0 | 237.5 | 317.2 | 61.8 | 69.4 | 28.8 | 47.4 | 84.5 | 107.5 | 30.4 | 32.6 | |
| VC + Ve | 565.0 | 682.2 | 552.8 | 733.1 | 37.4 | 44.8 | 22.5 | 27.0 | 232.2 | 310.8 | 58.1 | 65.6 | 31.1 | 51.5 | 77.2 | 100.3 | 27.2 | 30.7 | |
| MeJA | 580.6 | 694.0 | 548.8 | 728.1 | 33.2 | 40.1 | 20.8 | 25.2 | 229.9 | 307.3 | 54.0 | 60.8 | 35.7 | 55.1 | 70.1 | 89.9 | 22.2 | 28.6 | |
| AC | 599.3 | 709.2 | 544.9 | 721.5 | 25.7 | 35.0 | 19.0 | 23.1 | 229.3 | 303.5 | 46.5 | 55.8 | 40.6 | 59.6 | 62.0 | 83.1 | 17.8 | 26.2 | |
| Temperature | ** | ** | NS | NS | ** | ** | ** | ** | * | ** | ** | ** | ** | ** | ** | ** | ** | ** | |
| PGR | * | * | NS | NS | ** | ** | ** | ** | NS | NS | ** | ** | ** | * | ** | ** | ** | ** | |
| Temperature × PGR | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | |
| CV | 5.6 | 4.9 | 15.9 | 11.2 | 17.1 | 8.8 | 16.2 | 14.1 | 13.4 | 7.3 | 10.5 | 7.1 | 14.3 | 13.8 | 15.9 | 8.1 | 16.1 | 11.4 | |
PGR; CV; HHZ; IR-64; NS; ** and *; IP9G; Z; TZ9G; TZ9G; DIZ; ZR; IPA; DIHZR; IP; IPMP; HDT; HNT and AT stand for plant growth regulators; coefficient of variation; heat tolerant (HZZ); heat susceptible (IR-64); non-significant; significantly different at α = 0.01 and 0.05, Isopentenyl adenine 9-glucoside, Zeatin, Trans-zeatin 9-glucoside, Dihydrozeatin, Zeatin riboside, Isopentinyl adenosine, Dihydrozeatin riboside, Isopentenyl adenine, Isopentenyl adenosine 5’-monophosphate, high day; high night and ambient temperature, correspondingly. Vc; MeJA; Ve; Tr; Br, and AC represent vitamin C, methyl jasmonates, vitamin E, triazoles; brassinosteroids and control applied at the rate of 1.4, 1.8, 6.9, 0.55, 4.0, and 0 mg L–1, respectively.