Japonica Rice Yield Trials in Farmers’ Field of the Lower Northern Part of Thailand

Abstract

Japonica rice yield trials were conducted on farmers’ field to investigate the growth and development of the plant at Phitsanulok, Sukhothai and Uttaradit provinces during dry and wet seasons in 2004. The experimental design was RCB with 4 replications and 6 treatments. Four rice cultivars namely Koshihikari, Akitakomachi, Hiyoku and Yamadanishiki from Japan were compared with indica rice namely DOA 1 and DOA 2, recommended cultivars in Thailand, Results in dry season showed that the rice plant had well growth and yield. DOA 1 and DOA 2 at Uttaradit had 919 and 883 kg/rai yield which were higher than Koshihikari, Hiyoku and Akitakomachi that the yields were 734, 708 and 694 kg/rai respectively. Yamadanishiki cultivar gave the lowest yield at 522 kg/rai. In wet season, DOA 2 gave the highest yield at 735 kg/rai for Phitsanulok, while, Koshihikari gave the highest yield at 792 kg/rai followed by Hiyoku at 720 kg/rai at Sukhothai. No yield was harvested at Uttaradit due to the delayed planting. It was remarkably indicated japonica rice should be planted in the lower northern part of Thailand by deeply intensive practices or GAP practices.