Effect of Bulk Density and Seed Placement on Upland Rice Seedling Emergence
1968
Varade, S. B. | Ghildyal, B. P.
An experiment was carried out under laboratory conditions to find out the critical bulk density and seed placement depths for upland rice seedling emergence. Aluminum cylinders were used to accomplish various combinations af bulk densities and depths of seed placement by compacting soil at moisture content of 9%. Seedling emergences was observed till the 10th day after sowing in a constant temperature incubator of 35 C. Depths down to 8 cm with 1.6 g/cc or 0.7hg/cm₂ pressures and lower densities and pressures were not limiting for seedling emergence when moisture was above field capacity. Depths beyond 8 cm with these densities and below 5 cm with 1.7 and 1.8 g/cc bulk densities seem to be limiting. The pressure of 2.8hg/cm₂ at 10 cm depth became so critical that the emergence ceased totally. It seems that the mechanical impedance or the increased soil strength with increasing bulk densities affected seedling emergence adversely.
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