Review of different approaches to enhance resistance against fungal pathogens and transformation of the genes encoding hydrolytic enzymes from various sources to develop toleration of fungal diseases in transgenic plants

Fungal diseases are rated as one of the most important factors contributing to yield losses in many crops and different methods use to overcome these phytopathogens. Development of tolerant plants is one of the most efficient approaches against plant diseases which inhibit environment and product pollution because of reducing of chemical fungicides usage. In the past decades, by using modern biotechnology techniques, researchers have been isolated and transformed genes of interest to plants. By this precise and accurate transformation, a desirable gene is selected and inserted directly into plant cells. This technique enables us to gene transfer between species that would not naturally cross and allows breeders to use genes from plants and unrelated organisms such as fungi or bacteria. Some of the defense mechanisms which plants have evolved to respond to pathogens have been identified by studying host-pathogen interaction and responsible genes were isolated and transformed to plants. By the year 2011, no fungus resistant transgenic plant has released to market whereas herbicide tolerance, insect resistance, altered composition and viral resistance (few cases) have been the dominant traits of transgenic plants. In this article, several resistance strategies against fungal diseases and related mechanisms will be addressed. Furthermore the present review will focus on hydrolytic genes responsible of fungal diseases resistance and different sources of them. Transformation of hydrolytic genes from mycoparasitic fungi Trichoderma to potato (Solanum tuberosum L.) and biosafety concerns will be discussed as well.