The Institute of Microbiology, Chinese Academy of Sciences has made important progress in the systematic research of quarantine fungi in my country

Preventing the invasion of foreign harmful organisms is an important guarantee for realizing the sustainable development of China's agriculture and forestry and maintaining national ecological security
.

The quarantine pest list is an important law enforcement basis and work guide for port quarantine.
Among them, phytosanitary harmful fungi include 130 species, accounting for about 29% of the entire list
.

Since most of the fungi are small in morphology, it is difficult to simply rely on morphological characteristics for identification and identification, and their detection and prevention have always been difficult points in the work.
The detection rate of harmful fungi is far lower than that of other groups such as insects and weeds
.

Among the current national and industry standards for quarantine fungi, only 47 use molecular testing.
The root cause of this difficulty is that about half of the species in the quarantine fungi list lack model specimens, strains and reliable reference sequences, and The phylogenetic relationships of most species and their interspecific relationships with near-source species are still unclear, which greatly hinders the research and development of detection methods, not only making front-line quarantine personnel unfounded, but also building smart customs and guarding national biosecurity.
The key bottleneck
.

Cai Lei's team at the Institute of Microbiology, Chinese Academy of Sciences has long been committed to the classification, system evolution, and quarantine technology research of plant pathogenic fungi
.

Due to the particularity of harmful foreign fungi, it is difficult to carry out in-depth work on its active samples in China
.

The team used various methods such as field visits and research, international data cooperation, dried sample lending, etc.
, to check all 33 quarantine species (such as wheat leaf The current name, standard form, host range, geographical distribution, DNA barcode, system evolution status, typical disease symptoms, etc.
) of Phytophthora spp.
, lemon wilt bacteria, etc.
) have carried out a comprehensive monograph study, and in accordance with the international principle of “one bacteria, one” And the latest classification system, updated the current standard names of 23 species (Table 1)
.

Secondly, 4 selected patterns, 3 additional patterns, 2 new patterns and 5 voucher specimens were designated for species with missing or damaged type specimens, providing the most critical reference for the quarantine of these species
.

According to the latest research results of the research team on the systematic classification, the apple sphaerosporidium rot that originated in North America was treated as a new combination Xenosphaeropsis pyriputrescens (CL Xiao & JDRogers) F.
Liu, Crous & L.
Cai comb.
nov.
In addition, In this study, 17 quarantine species including wheat leaf blight (Alternaria triticina), potato gangrene (Boeremia foveata), cruciferous vegetable black shank (Plenodomus lingam) and other 17 quarantine species were sequenced, and the authoritative sequence was added to China The Phytosanitary Fungi Database (http://casbrc.
org/pqfungi/) provides scientific and authoritative data support for the subsequent research and development of high-precision detection technologies
.

The results of this research are expected to greatly improve the customs' detection level of quarantine cystomycetes, quickly advance the research and development of high-throughput detection chips, and provide an important reference for the next update of the quarantine list
.

Related research results have recently been published online as a monograph in the mycology journal Persoonia-Molecular Phylogeny and Evolution of Fungi (IF5y = 10.
667).
Dr.
Cai Lei’s research group at the State Key Laboratory of Mycology, Institute of Microbiology, Dr.
Zhao Peng, is the first author, Liu Associate researcher Fang is the corresponding author
.

The research was supported by funding from the Strategic Biological Resources Program of the Chinese Academy of Sciences, the Youth Innovation Promotion Association, and the National Natural Science Foundation of China
.

Original link: https://doi.
org/10.
3767/persoonia.
2021.
47.
02.
Table 1.
Canonical names, new model designations, new test reference genomes, morphological descriptions and barcode sequence updates of quarantine Pseudomonas fungi
.

Figure 1.
The additional morphological characteristics of the pine needle brown spot disease (Lecanosticta acicola) designated in this study for the first time in North America
.

This species is distributed in the northern hemisphere and can cause brown spot disease of 53 species of pines and hybrids, resulting in an average annual yield reduction of about 453,000 m3.
It is listed as a quarantine target by many countries in Africa, America, Asia and Europe
.

Figure 2.
This study clarified the phylogenetic status and interspecies relationship of the five quarantine fungi of the genus Pseudocercosis that first appeared in Indonesia, Japan, the United States, Angola, and Brazil
.

Figure 3.
Through comprehensive research on type specimens with a history of more than 70 years and fresh specimens intercepted recently in China, the quarantine species Parastagonospora pseudonodorum (Parastagonospora pseudonodorum, syn.
Leptosphaeria avenaria f.
sp.
triticea) was clarified for the first time.
The phylogenetic status and inter-species relationship
.

The data on the intercepted fresh specimens was provided by Shanghai Customs Researcher Yi Jianping
.

This study also clarified the world distribution of pathogens of other wheat crops that have not yet occurred in China
.