Suitable Planting Density for Chaiya Rice using Parachute Planting Method

Abstract

The effect of planting density on growth and grain yield of Chaiya rice using parachute planting was examined at Pathum Thani Rice Research Center, from September 2014 to January 2015. The particular objective was to examine the suitable planting density when parachute planting was applied. Five densities of Chaiya rice seedlings were thrown similar to parachuting. Those densities were 22,400, 30,720, 38,400, 48,000 and 56,320 clumps per rai (1 rai = 0.16 ha). Pre-heading growth varied greatly among densities; this variation was partly related to the number of tillers, lower densities having more tillers per clump than higher densities, respectively. The relationship between tiller number and plant height was not similar. The heights of rice at densities of 22,400, 30,720, 38,400, 48,000 clumps per rai were not significantly different within the group but these were significantly different with the planting density of 56,320 clumps per rai.
 Low densities promote head development as the number of heads per clump was higher than those of high densities in most densities. No significant effect of density on filled-grain and unfilled-grain per head. Seed weight per clump showed significant difference between densities except between those of 38,400 and 48,000 clumps per rai. Grain yield varied among densities. Chaiya rice with 22,400 clumps per rai had the highest yield at 786.38 kg per rai. However, it was not significantly different from yields of rice at densities of 30,720 and 38,400, clumps per rai. However, the grain yield of rice planted at 48,000 and 56,320 clumps per rai was significantly lower than that of 22,400 clumps per rai. It is concluded that there was a consistent effect of plant density on growth and yield of Chaiya rice using parachute planting.