Impact of moisture content on seed quality of combine-harvested rice varieties

The study was conducted with different rice varieties viz., TRY 3, CO (R) 50 and ADT 54 harvested using a tractor driven combine harvester with John Deere two wheel drive tractor across distinct moisture contents at various stages viz., at physiological maturity, two days, four days and six days after physiological maturity stage. The treatments aimed to deduct seed quality evaluation through physical parameters viz., broken seed, dehusked seed, pure seed and husk percentage, seed to husk ratio, mechanical properties and physiological properties of seed was evaluated using ferric chloride and further, whereas physiological parameters such as germination, seedling growth and vigour index. The result showed that harvesting at physiological maturity achieved 91 % germination rate, which subsequently decreased at six days after maturity stages to 86 %. Whereas seeding length, dry matter production and seedling vigour obtained during physiological maturity stage and six days after maturity stage of root length 24.6 cm and 22.7 cm, shoot length as 13.1 cm and 10.4 cm, dry matter as 0.150 and 0.121 (g/10 seedling), vigour index of 3350 and 2843 respectively. The chemical method using ferric chloride, detected 7.7 to 8.4 % mechanical damage irrespective of the varieties studied with different moisture levels. However, germination percentage from harvesting at physiological maturity stage or four to six days after maturity stages which maintain more than 80 % germination irrespective of the varieties studied and satisfied the Indian Minimum Seed Certification Standards.