Germination and Growth Efficiency of Khao Lao Take (Oryza sativa L.) under Drought Stress after Seeds Priming with Abscisic Acid and Paclobutrazol

บทคัดย่อ

The effects of seed priming in abscisic acid (ABA) and paclobutrazol (PBZ) on germination percentage, growth and total chlorophyll of rice (Oryza sativa L.) cv. Khao Lao Take were studied under drought stress. Rice seeds were primed in the various concentrations of 10 and 20 mg/l ABA and PBZ solution for 48 hours. Seeds were germinated and grown in soil-filled plastic pots for 14 days, then the seedlings were treated with drought stress by withholding water for 10 days. The results showed that seeds priming with all concentrations of PBZ were shown to promote seeds germination no different from the control, while priming with ABA caused to decrease of seed germination and primary root length. The growth of seedlings in drought stress found that seeds priming in all concentrations of ABA and PBZ increased seedling growth and total chlorophyll contents compared to unprimed seeds. However, fresh weight and dry weight of shoots and roots and chlorophyll contents were found in seeds priming with 20 mg/l PBZ compared to seeds priming with other treatment. This study revealed that seeds priming with 20 mg/l PBA tended to promote drought tolerant in rice cv. Khao Lao Take.