Vol. 13, Issue 8 (2024)

Author(s):
Tanzeela Yaseen and IT Nazki

Abstract:
The present investigation was conducted to evaluate the effect of ⁶⁰Co gamma irradiation doses (20, 30, 40, 50 and 60 Gy) on in vitro cultured shoots of (Rosa hybrida L.) cv.Avalanche. Significant decrease in establishment and survival percent of in vitro cultured shoots was reported under 40 Gy dose 37.50 and 40.83 and lowest recorded under 60 Gy 34.58 and 29.16 as compared to the control which recorded highest establishment and survival percent 95.95 and 90.05 respectively. LD ₅₀ value estimated at the end of 2^nd week by probit analysis was 32.28 Gy. Highest number of shoots 3.05 and 3.40, length of shoots 4.12 and 4.15 cm, leaf number 5.07 and 5.25 shoot¹ in VM₁ and VM₂ was recorded in control. Subsequent improvement observed in VM₂ over VM₁ cycle_. Shoot proliferation and rooting percent decreased with the increase in irradiation dose from 20 Gy 77.25 and 72.66 to 60 Gy 30.83 and 32.50. Control resulted in highest rates in survival percent of 95.80 while as 60 Gy of ⁶⁰Co gamma irradiation resulted in 35.08 survival percent of rooted plantlets during primary hardening.