Study On The Intestinal Microecological Affects The Reproduction Mechanism Of The Bombus Lantschouensis Queen

Bombus lantschouensis is a common species of bumblebee in China.It has become a major artificial breeding species because of its large population,adaptability,and ease of rearing.The queen bee plays a key role in the establishment,development and demise of bee colonies,however,the degeneration of queens during the breeding process hinders its further application.The intestinal flora of organisms plays an important role in many aspects of the host,such as the food digestion and absorption,affecting host mating and enhancing the host's fertility,etc,and the change of metabolism in organisms which can reflect their physiological and biochemical characteristics.Based on the understanding of the phylogenetic relationships of Bombus lantschouensis which is among the Bombus,the paper tried to study the change of the intestinal dominant bacteria and different metabolites and metabolic pathways of the queen under different physiological states,and to understand the possible relation between the change of predominant bacteria and different physiological conditions of queens.The main findings are as follows:1.Phylogenetic relationships between Bombus lantschouensis and other bumblebee speciesThe phylogenetic tree was constructed by combining multiple genes and using Bayesian analysis and maximum likelihood method.The results showed that the genus of Bombus was divided into two clades,the short-faced and long-faced.Bombus lantschouensis belongs to Bombus s.s.which fall into the short-faced,and it is the same subgenus as Bombus terrestris.These results are consistent with the morphological identification.The subgenus of bumblebee has unique sociobiology characteristics which is easy to manage and suitable for pollination.So this provides theoretical support for the continuous indoor breeding of Bombus lantschouensis.2.Changes of the dominant bacteria of the queens in different physiological statesHigh-throughput sequencing of mated,unmated,oviposition and Non-oviposition queens' genomic DNA using the 16S rRNA gene showed that the dominant intestinal bacteria in mated queens were Bacillus,Pseudomonas,and Lactococcus,while the other three were Gilliamella,Snodgrassella,Lactobacillus,and Bifi-dobacterium.The result indicated that there are differences in the species and content of the dominant bacteria of the queens in different states.3.Changes of copy number of dominant bacteria in queens at different time pointsFirst we get the total bacteria copy numbers in different physiological state of the queen at different time points total bacteria copy number,and then investigate the main bacterial genera copy numbers at different time points of three groups,the copies of Gilliamella,Snodgrassella,and Lactobacillus are gradually increasing with the change of time(1-7d)in the unmated queen,while in the mated queens which are reducing with the change of time(1-7 d),but they have also high copy numbers in the oviposition queen,the result are consistent with total bacteria copy numbers(16 s)changes in different groups,yet the change of total bacterial copy numbers are not significant.The copy numbers of Bacillus,Lactococcus,and Pseudomonas showed that they are gradually increasing with the change of time(1-7d)in the mated queen,while the contents are low in unmated and oviposition queens.The genus of Bifidobacterium only have the high copy numbers in the oviposition queen.4.Metabolomic analysis of hemolymph from queens under different physiological conditionsGC-MS was used to detect and analyse the metabolome of unmated,mated and oviposition queens'hemolymph.The results showed that there were 12 different metabolites between mated and unmated queens,12 different metabolites between mated and oviposition queens,and 13different metabolites between unmated and oviposition queens.The metabolites include amino acids,carbohydrates,lipids and other small molecule compounds,and involving the relative pathway which include Methane metabolism,Glycine,serine and threonine metabolism,Aminoacyl-tRNA biosynthesis,Starch and sucrose metabolism,Citrate cycle,Galactose metabolism,Glutathione metabolism,Arginine and proline metabolism,and Sphingolopid metabolism,and these metabolites and metabolic pathways are possible to associated with the change of intestinal bacteria in the queen of different physiological states.