Table 4.
Effect of weed competition period on aboveground crop biomass production in aerobic rice variety AERON 1 at different growth stages in both seasons (off-season 2010 and main season 2010/2011 (g/m2)).
| Weed competition period | Off-season 2010 | Main season 2010/2011 | ||||
|---|---|---|---|---|---|---|
| Panicle initiation stage | Heading stage | Harvest | Panicle initiation stage | Heading stage | Harvest | |
| Weedy until 2 WAS | 191.77a | 364.35b | 660.71ab | 201.89a | 328.23ab | 669.60b |
| Weedy until 4 WAS | 83.20c | 293.42c | 631.00b | 81.40c | 306.60b | 652.00b |
| Weedy until 6 WAS | 80.32c | 215.00d | 443.53d | 76.00c | 241.14c | 431.30d |
| Weedy until 8 WAS | 77.43c | 119.42f | 235.42e | 75.28c | 111.00e | 205.55e |
| Weedy check | 77.59c | 108.29f | 169.00f | 75.67c | 91.59e | 130.49f |
| Weed-free until 2 WAS | 165.30b | 158.00e | 247.48e | 151.35b | 169.47d | 253.67e |
| Weed-free until 4 WAS | 208.57a | 302.66c | 553.00c | 185.48a | 302.62b | 589.07c |
| Weed-free until 6 WAS | 208.98a | 364.7b | 664.36ab | 197.73a | 336.67ab | 654.23b |
| Weed-free until 8 WAS | 210.10a | 381.85ab | 673.00ab | 204.16a | 353.72a | 687.58ab |
| Weed-free check | 209.00a | 406.00a | 679.45a | 202.31a | 359.87a | 729.33a |
Within a column for each factor, means sharing same alphabets are not significantly different at P = 0.05 probability level according to least significant difference test.
WAS = weeks after seeding.