Effects of sand priming on germination and field performance in direct-sown rice (Oryza sativa L.)

A priming method called sand priming was developed using sand as a priming solid matrix in present experiment. Seeds were mixed with sands that contained 3.8% (v/w) water and scaled in plastic box and then were primed at 18 degrees C for 72 h. Four varieties of rice were used to investigate the effect of sand priming on germination of direct-sown rice (Oryza sativa L.) in the laboratory. The results showed that the energy of germination, germination percentage, germination index and vigor index were improved in four varieties. Meanwhile, seedling height, root length, number of root and root dry weight were significantly higher than the nonprimed controls. Field experiments showed that the seed establishment and yield in sand primed seeds were significantly increased by 19.8% similar to 22.9% and by 9.8% similar to 31.2%, respectively as compared to soaked seeds without priming. It is indicated that sand priming method may help to improve seedling establishment in direct-sown rice and possible to be used in the field crop production.