Production of virus free planting material through meristem culture in short day garlic cultivars Bhima Omkar and Bhima Purple

Abstract

Aim: Low productivity of garlic in India has been attributed to viral infestation of planting material. In vitro techniques offer a suitable alternative; hence, standardization of protocol to raise virus free planting material through meristem culture in vitro and its multiplication was planned. Methodology: Response of different cytokinins viz. BAP, Kin (1 and 1.5 mgl-1) in combination with NAA (0.1, 0.5 mgl-1) on basal MS medium was evaluated for inducing multiple shooting through meristem tip (0.1 – 0.3 mm) in vitro in two garlic cultivars viz. Bhima Purple and Bhima Omkar. Higher sucrose (6 to 11 %) along with cytokinins was evaluated for in vitro microbulbils induction. Viral load was tested at different stages using potyvirus specific alkaline phosphatase based direct antigen coating ELISA kit. In vitro raised microbulbils were transferred to three production cycles to get normal size garlic bulb. Results: MS + 1 mgl-1 Kin + 0.1 mgl-1 NAA medium was the best performing medium for induction of multiple shooting in both the cultivars. About 70% mericlones were free from viruses in both the cultivars. Liquid medium MS + 1 mgl-1 Kin + 6% sucrose produced the highest number of microbulbils than other treatments. Normal garlic bulbs (9-12 cloves/bulb) were produced in field from in vitro raised microbulbils after two cycles of production in polyhouse followed by field transplanting. Interpretation: In vitro meristem culture is an efficient method for producing virus free planting material of garlic. Protocol for production of higher number of microbulbils in vitro has also been standardized. Using Online C standardized protocol a normal size garlic bulb can be produced in three production cycles.