Resistance of backcrossing lines with lysozyme gene to rice blast

It is of great significance to enhance blast resistance of parent elite hybrid rice by utilizing foreign genes with wild-spectrum resistance. In this paper, resistant spectrum and field-neck resistance of backcrossing lines with lysozyme gene were analyzed to enhance further understanding and improvement capacity of the gene. Artificial inoculation and field-neck resistance tests show that backcrossing lines have resistant frequencies of 90% and are susceptible to 6~8 strains in all of 76 strains of Magnaporthe grisea. Backcrossing lines are therefore ranked as a resistant (R) grade compared with recurrent parent “Minghui63” with 72.37% resistance frequency and susceptible to 21 fungus — ranked as middle resistant (MR) grade. T-test shows that backcrossing lines with lysozyme gene have a more notable field-neck resistance than the recurrent parent “Minghui63”. It achieves 10% reduction of disease incidence and 15% of disease index, making backcrossing lines as R grade and recurrent parent “Minghui63” as MS grade. From the above findings, it is concluded that foreign lysozyme gene broadens resistant spectrum thereby enhancing resistance against rice blast fungus. Transferring lines with lysozyme gene can therefore be available for breeding resistant rice variety.