BALA SUBRAMANYAM SIVARATHRI*, A.R. NIRMAL KUMAR, V. UMAMAHESH AND D. SUBRAMANYAM

Department of Crop Physiology, S.V. Agricultural College, ANGRAU, Tirupati-517502.

ABSTRACT

Poor seedling establishment is one of the major constraints in adopting dry direct sown rice. The objective of this study

was to determine the effectiveness of seed priming treatments for improving crop stand establishment, seedling vigour index and speed of germination. Two laboratory experiments were conducted at dept. of Crop Physiology, S. V. Agricultural College, Tirupati, Acharya N.G. Ranga Agricultural University, Andhra Pradesh, India, during 2021-22 with eight seed priming treatments broadly consisting of untreated control; hydropriming; priming with GA₃ @ 100 ppm; priming with KNO₃ @ 0.5%; priming with DAP @ 2% and their possible combinations. Seed priming improved germination percentage, crop stand establishment and seedling vigour index along with speed of germination. Faster and uniform emergence of seedlings might be due to improved α-amylase activity by GA₃ which in turn increased the levels of soluble sugars in priming treatments. Priming combination of GA₃ @ 100 ppm + KNO₃ @ 0.5% + DAP @ 2% gave superior results among all the treatments in both laboratory experiments.

KEYWORDS: Dry direct seeded rice, Seed priming, Crop stand establishment, Seed vigour index, Speed of germination.