Optimization of Agrobacterium mediated callus-based transformation protocol for rice (Super Basmati) and GUS expression

Abstract

Rice (Oryza sativa L.) is a staple food in many countries of the world. The world population is increasing at a tremendous rate. The demand of food is increasing but supply is limited due to decrease of agriculture land, biotic and abiotic stresses. There is need of time to increase the yield of food crops including rice by incorporating resistance genes that will improve the ability of cultivar to resist biotic and abiotic stresses. Agrobacterium mediated callus-based transformation is one of the techniques for insertion of gene of interest. This study was an attempt to evaluate the response of four cultivars (Super Basmati, Basmati 370, Basmati 385 and Shaheen Basmati) of rice for regeneration and transformation on the basis of hygromycine. The cultivar super basmati responded best response so further GUS expression of this cultivar was done to check the transformation efficiency. The EHA101 Agrobacterium strain, plasmid containing GUS gene was used to evaluate the transformation rate. The factors affecting transformation process were optimized. The results revealed that 500 mg/L of cefotaxime was best concentration to decontaminate the left-over bacteria. The 50 mg/L of hygromycine was optimized as lethal dose for selection of transformed calli. The (100 µM/L) of acetosyringone in cocultivation media enhanced the ability of Agrobacterium to deliver the required gene in the calli. Out of four cultivars of rice, super basmati showed the best response for regeneration and transformation. The 24% GUS expression was recorded in the leaves of super basmati. © 2021 The Author(s)