Comparison of differences in physicochemical properties and fungal community structure of paddy at different positions in real warehouses using high-throughput sequencing

LI Xinwei; GAO Xianglan; DENG Wei; ZHANG Zongrui; ZHOU Gangxia

doi:10.12187/2025.03.001

Abstract：Paddy samples at different positions in real warehouses were monitored for 12 months to determine their moisture content,fatty acid value,and total mold count.The changes in fungal community structure were analyzed using high-throughput sequencing technology.The results showed that as storage time prolonged,the moisture content of paddy samples at center positions(CS,LTS,LTS2)and peripheral positions(SS,HTS,HTS2)decreased,while the fatty acid value increased.The total mold count of SS samples was higher than that of CS samples at the same time point,whereas mold growth and reproduction in HTS2 samples were inhibited,resulting in a lower total count compared to LTS2 samples at the same time point.For paddy samples at peripheral positions,the Chao1 and Observed species indices gradually decreased,while the Shannon and Simpson indices first decreased and then increased.The Pielou's evenness index of paddy samples at center positions was higher than that of samples at peripheral positions at the corresponding time points.The Chao1,Observed species,Shannon,and Simpson indices ofpaddy samples at center positions first increased and then decreased,and the Good's coverage index for all samples was greater than 0.99.The fungal communities in paddy samples from different positions were classified into five main phyla:Ascomycota,Basidiomycota,Mucoromycota,Olpidiomycota,and Mortierellomycota.Fungal genera such as Magnaporthe and species such as Parastagonospora_poae exhibited distinct variation trends in paddy samples from different positions.Furthermore,among all paddy samples,38 ASV/OTU were shared.LTS samples had the highest number of unique fungi,while SS samples had the lowest.In addition,principal component analysis(PCA)revealed that paddy samples at peripheral positions were relatively dispersed in distribution,while those at center positions were relatively concentrated.This indicates that,compared to peripheral positions in real warehouses,center positions provide a more stable microenvironment,which is more favorable for maintaining grain conditions.