A basic scheme of soybean transformation for glyphosate tolerance using Agrobacterium tumefaciens through an approximation of patents: a review

Abstract

Concern has been expressed on the control of agricultural biotechnology through patents that may adversely affect the development of competing crops. Soybean is one of the most important crops around the world (~287 million t per year), above potatoes (45 million t per year), tomatoes (23 million t per year), or wheat (116 million t per year), with prices for American producers ranging between USD 278.8 and USD 650.3 t-1. Soybean belongs to the Fabaceae family and has been genetically modified (GM) to improve its tolerance to herbicides, including glyphosate, its resistance to insect pests, and the quality of soy oil. Glyphosate-tolerant soybean has received a gene coding for the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). There are a number of variables that contribute to the development of a GM soybean event. Such variables include tissue culture, selection methods, cloning vectors, and Agrobacterium strains that affect transformation efficiency and can be associated with patents. Chlorine gas disinfection is the most appropriate technique for plant material. Production of explants with shoots and molecular and phenotypic features (e.g., antibiotic susceptibility) of bacterial strain must be assessed. A long-term glyphosate selection arrangement is the most suitable and a consistent approach for the selection of events of GM soybean with tolerance to glyphosate. Freedom-to-operate evaluation must be carried out to find the specific elements neccesary for GM plant development that do not infringe the rights of third parties. These rights come into effect from the patent application date for a definite geographical region involving construct design and its synthesis, transformation vector, bacterial strain, methods, or reporter gene. In this review, the protocols relating to experiments for the development of GM soybean using an epsps gene are included, and considerations relating to intellectual property rights are involved. The major elements associated with each stage of the development of patents are described including the following: the soybean genotype, seed disinfection, genetic construct design and its synthesis, tissue culture protocols, selection strategy without gene reporter, and Agrobacterium strain. This review is a guide for carrying out technical procedures when the desired product is the off-patent GM soybean with tolerance to glyphosate.