Field appraisal of seed priming to improve the growth, yield, and quality of direct seeded rice

摘要

Poor crop stand and high weed infestation are the major constraints of direct seeded rice. Seed priming has the potential to improve the seedling emergence and crop stand. This study was conducted to evaluate the on-farm assessment of direct seeded rice by employing different priming techniques such as on-farm priming, hydropriming, hardening, and osmohardening with CaCl2 and KCl. Untreated seeds were taken as control. Among all the seed priming techniques, osmohardening with CaCl2 improved the stand establishment, allometric response, agronomic traits, yield, and quality of harvested paddy compared with other priming techniques, and non-primed control in direct seeded culture. Improved crop stand as indicated by lower values of time to emergence and higher values for emergence index and final emergence, higher crop growth rate, and improved plant height, tiller numbers, and straw and kernel yield with high harvest index were recorded from osmohardening with CaCl2. In addition, seed priming treatments also improved the kernel quality. Osmohardening with CaCl2 was the best way to reduce sterile spikelets, abortive and chalky kernels, and improve kernel length. However, none of the seed priming techniques could improve the number of kernels per branch, 1000-kernel weight, kernel width, and kernel water absorption ratio. Moreover, improved phosphorus, calcium, and potassium contents were also observed from osmohardening with CaCl2 followed by KCl. Osmohardening with CaCl2 can therefore be employed for better crop stand, growth, yield, and quality in direct seeded rice. Key words: Direct seeded rice, field appraisal, quality, seed priming, stand establishment