Vegetos

Abstract

Two diverse and improved varieties of, linseed crops namely T-397 and Shekhar were exposed to different doses of gamma rays viz. 40, 50 and 60 kR a Co⁶⁰ source at the National Botanical Research Institute, Lucknow. Yield in oilseed is a complex trait in which plant height, number of branches per plant, number of pods per plant, grain yield per plant and seed weight constitued to be the major yield components. Addition to this types of mutagen and different dose of mutagens are also important in relation to creation of variability. The present findings on induced polygenic variability in two varieties of linseed (T-397 and Shekhar) clearly exhibited the significant differences between the mean values recorded for different populations of mutagenic treatments and the control for all the chraracters studied. The behaviour of varieties was observed to be changed for survival of plants scored at maturity where T-397 had higher percentage of plant survival as compared to Shekhar. The means of treated populations shifted in negative directions as compared to that of control. Based on Lethal Dose₅₀ (LD₅₀) as to minimize DNA damage and reduce undesirable mutations, radiation doses which lie between 40 and 60 kR of gamma-rays can be considered suitable for induction of mutation in linseed varieties. It is important to note that the doses or concentrations of mutagens selected had negative effects on mean but showed positive effects on variability for grain yield per plant.