Probit analysis and effect of electron beam and gamma rays in blackgram (Vigna mungo (L.) Hepper)

Abstract

An experimental investigation was carried out to determine the lethal dose (LD50) of electron beam and gamma rays on two black gram varieties viz., MDU 1, VBN (Bg) 4. The lethal dose was determined by probit analysis. Dry seeds of both the varieties were treated with electron beam and gamma rays on different dosage viz., 100 Gy, 200 Gy, 300 Gy, 400 Gy and 500 Gy for Gamma rays and 200 Gy, 300 Gy, 400 Gy, 500 Gy and 600 Gy for electron beam along with the control (non-treated). LD50 dose for Electron beam on MDU 1 and VBN (Bg)4 was 304.91Gy and 302.21 Gy whereas, LD50 dose for gamma rays on MDU 1 and VBN (Bg) 4 was 324.89 Gy and 318.12 Gy respectively. The germination percentage and survival percentage of both varieties were gradually reduced with increasing doses of electron beam and gamma rays. The shoot length, root length, plant height at 30th day, pollen fertility and seed fertility were also decreased gradually with increasing doses of electron beam and gamma rays. The LD50 values determined for the different blackgram varieties could be useful in blackgram varietal improvement programme in future.

Keywords

• electron beam
• gamma rays
• ld50 value
• and germination