Turnip cabbage, each has some love. But there is such a goods, not only pay attention to cabbage, not only love radish cabbage, cross flower sage other vegetables, such as rape, broccoli, kale, mustard, etc. , are also their focus on feeding objects. This is a small dish! The grasshopper is a globally recognized killer of crucified plants, with no distribution record in Antarctica, and is the most widely distributed worldpest.
Their high reproductive capacity and high levels of resistance make prevention and treatment very difficult, resulting in crop yield loss and cost of up to $4-5 billion per year.
Previously, based on the distribution of the parasitic natural enemies of the cruciferous plants and small vegetables, scholars from all over the world put forward the hypothesis that the small vegetables originated along the Mediterranean coast, South Africa and China.
On May 8, 2020, Nature Communications magazine published the results of the research on small vegetable groups involved in the National Key Laboratory for The Prevention and Control of Harmful Pests of Crops in Fujian University, the University of China, the University of British Columbia, the University of Melbourne, the University of Tianjin, the University of Adelaide, Brooke University, charlest university, the British Museum and other research institutions and organizations from several countries. In 2012-2014, the research team collected approximately 5 samples from 114 sampling sites in 55 countries and regions on six continents, using whole genome sequencing techniques and group analysis techniques, combined with genealogical geography research, to conclude that the origin of the leeks is South America, rewriting the academic community’s previous understanding of the origin and evolution of the grasshoppers and the origin of the problems associated with the small vegetables.
The team used short-read long sequencing techniques to sequence the entire genome of the sampled small vegetable-to-eat individuals. The actual effective sequencing depth of 532 small vegetables in each individual worldwide was distributed between 5.3 and 17.41X, with a total of 40,107,925 SNPs and 22,736,441 indels detected. The analysis found that the genome variation of the small vegetable grasshopper presents a global pattern, the individual SNP has regional diversity, the common SNP ratio is low, these characteristics reflect the high level of polymorphism of the small vegetable genome, is the small vegetable grasshopper can successfully achieve global expansion and adapt to the environment of different parts of the world.
Figure 1 Global sampling points and global 532 small vegetables with whole genome variation
a. The acquisition point consists of 114 sampling points on six continents, excluding Antarctica, with approximately 5 individuals per sample point; Genomic variation of the global cauliflower: the ring from the outside to the inside is THE SNP, the nucleotide polymorphism, Indels;c. Mixed SNP/Pure SNP differences across continents.
The discovery of the closest distance between the SA group grasshopper and the outer Group Australian leek swashes through the genome-wide SNP-building group Evolutionary Tree, consistent with the results of using mitochondrial genomes and COI genes to build an evolutionary tree, reveals that the origin of the small vegetable stork is South America.
Figure 2 Origin and Global Distribution of small vegetables
a. Evolutionary tree based on the nuclear genome SNP, with Australian cauliflower as an outer group; The genetic structure of the small vegetable group; c. PCA;d. The dXY analysis shows the genetic differences between different groups of small and Australian leeks, reflecting the global expansion of the leeks.
The research team analyzed the size and differentiation time of the small vegetable group using the SMC algorithm, and found that the small vegetable grasshopper experienced three major differentiations and expansions.
Figure 3 The origin and expansion path of the leeks in the world
a. The evolution of group history illustrates the size and time of differentiation of small groups of vegetables; The study predicts a road map for the global migration of small groups of vegetables, with red arrows indicating the spread of leeks from South America to other continents.
So far, the research team through the genomics of the small vegetable grasshopper group, not only solved the controversy surrounding the origin of the small vegetable grasshopper, determined the origin of the small vegetable grasshopper, pointed out the direction for the search for effective biological control of natural enemies, but also analyzed the genetic basis of the adaptability of the environment and pesticides, which provides an important scientific basis for the production, evolution and management of the small vegetable grasshopper resistance.