Effect of mutagens on in vitro seed germination and growth of rough lemon (Citrus jambhiri) seedlings

Abstract

An experiment was conducted during 2008–09 at Ludhiana to study the effect of various mutagenic treatments on germination and growth of rough lemon (Citrus jambhiri Lush.) seedlings. Developmental characteristics of the in vitro derived plantlets from treated seeds employing gamma radiation at 0, 20, 40, 60, 80, 100 and 120 Gy and the alkylating agent ethyl-methane sulfonate at 0, 0.2, 0.4, 0.6, 0.8 and 1.0% (v/v) were evaluated. Seeds were sown in Murashige and Skoog nutrient medium under controlled laboratory conditions (25±2°C, 16 hr photoperiod, 2000 lux).The dose required to kill half of the tested population (LD50)corresponded to 62 Gy for gamma radiation and 0.64% for ethyl methane sulphonatetreatment. Number of days taken for seedling emergence increased with increasing dose of gamma irradiation and ethyl methane sulphonate. Seed germination,seedling height,internodal length, number of leaves, leaf area, number of branches, root length and number of secondary roots decreased with increasing dose of gamma radiation and ethyl methane sulphonate.