At present, the pine industry is facing severe pine wood nematode disease hazards. The team of Zhou Zhichun, a researcher at the Institute of Subtropical Forestry, Chinese Academy of Forestry, carried out a number of studies based on the relationship between pine resin and pine wood nematode disease resistance.
Pine massoniana infected with pine wood nematode disease versus high resistance to pine wood nematode disease Pinus massoniana. Photo courtesy of Yalin, Chinese Academy of Forestry
Recently, the team identified PmNBS-LRR97, a new gene resistant to pine wood nematode disease in Pinus massoniana. The findings were published online in the International Journal of Molecular Sciences.
China’s Pinus massoniana covers an area of about 8.04 million hectares, with an annual output of 500,000~700,000 tons of pine resin, accounting for more than 70% of the total amount of pine resin in the country. According to the announcement of the State Forestry and Grassland Administration (No. 6 of 2022), pine wood nematode disease has spread to 19 provinces (autonomous regions and municipalities), harming about 2 million hectares of pine forest and about 20 million dead plants. The harmful tree species have also gradually spread from Pinus massoniana and Pinus nigra to the north to Pinus tabulosa, Pinus knotensis, Larch and other species, of which Pinus massoniana accounts for more than 90%, with a loss of hundreds of billions of yuan.
When plants encounter threats such as pests and diseases, they can activate the innate immune system like animals, in which the disease resistance (R) gene recognizes pathogens to activate two types of immune responses to make plants resistant. The largest of these is the NBS-LRR gene containing nucleotide binding site (NBS) and leucine repeat (LRR), which is lacking in NBS-LRR-related gene studies in Pinus massoniana.
In this study, the NBS-LRR gene family in the transcriptome of Pinus massoniana stems was first identified, grouped and structured, and a total of 507 disease resistance genes containing NBS domains were identified, divided into 8 subclasses. They found that the PmNBS-LRR97 gene located on the cell membrane was involved in the defense response against pine wood nematode disease, which was significantly upregulated after pine wood nematode infection, and was highly expressed in the stem, and could promote the production of reactive oxygen species by activating the expression of reactive oxygen species-related genes, which helped Pinus massoniana to inhibit the infection of pine wood nematode disease.
The discovery identified the new gene of resistance to pine wood nematode disease in Pinus massoniana, provided a theoretical basis for the construction of a molecular design breeding system for Pinus massoniana, laid a research foundation for the cultivation of new varieties of Pinus massoniana resistant to pine wood nematode disease, and helped to promote the breeding level of pine in China from the era of conventional breeding to the era of molecular design breeding.
Yini Xie, Ph.D. student, is the first author, and researchers Zhou Zhichun and Liu Qinghua are the corresponding authors. The research was supported by the Key R&D Program of Zhejiang Province, the National Natural Science Foundation of China, the Major Special Project of Breeding Science and Technology of New Agricultural Varieties of Zhejiang Province and the Forestry Science and Technology Innovation Project of Jiangxi Forestry Bureau. (Source: Li Chen, China Science News)
Related paper information:https://doi.org/10.3390/ijms24031812