Drought is a major factor threatening global food production. Overexpression of drought resistance genes is the simplest and direct means to improve the drought resistance of crops. However, gene overexpression is often accompanied by some side effects, such as affecting the growth and development of plants under normal conditions. This is also one of the reasons why the overexpression of many drought resistant genes cannot be applied in the field. Recently, Professor Lu Yanli’s team from the State Key Laboratory of Southwest crop gene discovery and utilization of Sichuan Agricultural University published a research paper entitled”ABA inducible deeper rooting 1improves adaptation ofmaize to water deficiency” in the well-known botanical journal plant biotechnology Journal (SCI influence factor 13.263), which uses drought induction strategy to express corn dro1 gene, Finally, transgenic maize with excellent drought avoidance ability in the field and no yield reduction under normal conditions was obtained.
Deeper rooting 1 gene can promote the growth of plant roots to the deep layer of soil, so as to better absorb water. Studies have shown that the greater drought tolerance of ruminant grass (Mexican maize) than maize inbred line B73 is due to the more sensitive response of ruminant grass zmdro1 to drought /aba, and its roots can be better distributed to deep soil under drought. Therefore, the authors used drought /aba induction strategy to express zmdro1. There are some background high expression lines in transgenic maize, but their growth and development is obviously weak, indicating that the overexpression of zmdro1 is not conducive to plant growth. Transgenic maize with low background expression and high drought /aba induction showed good drought avoidance ability in the field, which can greatly improve the yield under drought stress, and will not reduce the yield under non drought conditions. This research strategy promotes the application of zmdro1 in maize drought resistance breeding, and also provides a reference for the utilization of other drought resistance genes.
Feng Xuanjun, a young teacher of the State Key Laboratory of Southwest crop gene mining and utilization, Sichuan Agricultural University, and Jia Li, a doctoral student, are the co first authors of the paper, and Professor Lu Yanli is the corresponding author. The research was supported by the national key research and development plan, the National Natural Science Foundation and other projects.