), maximum tillering (Max ), panicle initiation (PI), booting (BT

), maximum tillering (Max.), panicle initiation (PI), booting (BT), heading (HD) and maturity (MA) stages. Plant samples were separated into stem (the vegetative parts including leaf blades, culm plus sheath and dead tissues), panicles (at BT, HD, 12DAH and MA stages) and spikelets (at maturity stage). The vegetative plant parts were oven-dried at 70 °C to constant weight and then weighed to calculate the stem dry weight of the respective stage. Panicle number was counted from the 12 hills and 0.48 m2 sampled area at maturity stage. At MA, a 5 m2 area was harvested for grain yield and the grain was adjusted to a 14% moisture level. Tillering duration (TD) was calculated from sowing to the date of

maximum tiller number. Tillering rate (TR) = the maximum number tillers / TD. Panicle bearing tiller rate (PBTR) = (number of panicles per Epigenetic signaling inhibitor selleck chemical m2 / number of maximum tillers per m2) × 100. Tiller mortality at different growth stages = (TL1 − TL2) / TL1 × 100, where TL1 is the total tiller number at time T1, and TL2 is the total tiller number at time T2. Mid. is defined as the midpoint between TP and PI. The PI stage was determined by dissecting five main stems starting

from 40 DAT. BT was measured at 20 days after PI. HD was taken as the time when 80% of stems had more than 50% of panicle exerted. The crop reached maturity when 90% of the spikelets turned from green to yellow. Canopy height was measured from the soil surface to the top level of the canopy at every growth stages. Statistical analyses were performed using Statistix 9, analytical software, Tallahassee, FL, USA. Means of cultivation methods were compared according to the least significant difference (LSD) test at the 0.05 probability level. Figures were constructed

using Microsoft Excel 2003. Although the results were higher in 2012, all parameters showed similar trends among treatments in both years. For this reason, analyses were performed using the combined results of the two years. Canopy height (cm) varied significantly among the treatments at all crop growth stages except BT. Canopy height increased with time from Mid. to HD stage. At every sampling date, TP rice had higher canopy height than DS rice. At HD, the highest canopy height (127.1 cm) was found under the CTTP treatment and NTTP, Sucrase CTDS and NTDS resulted in lower and statistically identical canopy heights (Fig. 1). Tiller number varied significantly among the treatments at all crop growth stages. Tiller number under DS was always higher than under TP irrespective of tillage system at all growth stages and was higher under CTTP than under NTTP except at the Mid. stage. At Max. stage, CTTP showed a significantly higher tiller number (512 per m2) than NTTP (454 per m2) but both NTDS and CTDS showed statistically identical tiller numbers (624 and 612 per m2 respectively). NTTP showed the lowest tiller number among the treatments (Fig. 2).

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