Seed Pelleting with Bacillus subtilis on Seed Quality and Seedling Growth of Khao Dawk Mali 105 and RD69 Rice Seed Varieties

In rice seed production, farmers continue to encounter problems related to diseases and insect infestations at various stages of the process. Consequently, seed pelleting technology and plant-promoting microorganisms are applied together to solve such problems. This experiment investigated seed quality and seedling growths of rice seeds following pelleting with Bacillus subtilis at varying ratios. This experiment was conducted at Seed Technology Laboratory, Faculty of Engineer and Agro-Industry, Maejo University, and was divided into five methods: non-pelleted seed (T1), pelleted seed without Bacillus subtilis (T2), pelleted seed in combination with Bacillus subtilis at three different concentrations (1, 2, and 3 milliliters (T3-T5). Following the pelleting process, the pelleted seeds were taken for seed quality testing and evaluation of seedling growth. The results of the seed quality testing indicated that pelleting Khao dawk mali 105 and RD69 rice seed varieties with 1, 2, and 3 milliliters of Bacillus subtilis had germination percentages non-statistically different from non-pelleted seed. However, there was a tendency to increase seed germination in both laboratory and greenhouse conditions. When assessing seedling growths, it was observed that pelleting had an impact on the seedlings of both rice varieties. Specifically, there was a decreasing trend in seedling shoot length for the Khao dawk mali 105 rice seed variety while pelleted seeds with 1 and 3 milliliters of Bacillus subtilis for both rice varieties exhibited longer root lengths, with an increase ranging from 5% to 30% compared to non-pelleted seeds. Additionally, it was noted that rice seedlings germinated from pelleted seeds with 1, 2, and 3 milliliters of Bacillus subtilis exhibited superior growth compared to seedlings from non-pelleted seeds and pelleted without Bacillus subtilis.