Effect of Age and Number of Seedling per Hill on Yield of Japonica rice cv. DOA1 Planted in Central Thailand

Abstract

Japonica rice has a niche market with high price in Thailand. It is well adapt to the temperate
areas, it was planted only in upper Northern and Northeasthern Thailand. Interesting that it can be grown
in central plain of Thailand and how to grow for economically return. The experiment was conducted to
study effect of number of seedling per hill viz., 1, 2 ,3 seedlings/hill, and seedling age viz., 3, 4, 5, 6 wks
on yield of japonica rice (Khao Yipun) cv. DOA1. The experiment was carried out at the experimental’s
field of the Faculty of Agricultural Technology, King Mongkut’s Institute of Technology Ladkrabang,
Bangkok during 1 Nov, 2013–15 Mar, 2014. The 3x4 factorial arrangement in the randomized
complete block design with 3 replications and hill space was 25x25 cm. Data were recorded from 10
hills/experimental unit. The seedling age showed highly significant affected on yield of DOA1. The 3 and
4 wk ages produced a non-significant difference grain yield of 483.17 and 477.81 kg/rai, respectively.
However, they were significantly higher than that of the 5 and 6 wk ages which yield were 393.62 and

365.19 kg/rai, respectively. The effect of number of seedling per hill on yield were non-significance.
The 1, 2 and 3 seedling per hill had grain yield of 435.57, 397.43 and 456.85 kg/rai, respectively. Result
indicated that DOA1 can be grown economically on off-season in central plain of Thailand. Transplanted
of a 3-4 wks age for 1 seedling/hill in space of 25x25 cm was a recommended method.