Response of Endophytes in Potato Leaves to the Feeding Stress of Phthorimaea operculella

Purpose To investigate changes in the structure and diversity of endophytic bacterial communities within potato leaves following feeding stress by potato tuber moths (Phthorimaea operculella), providing theoretical support for research on potato insect resistance mechanisms and the exploration of beneficial plant endophytic microbial resources.

Methods Potato variety Hezuo 88 was used as indoor potted material. Third-instar larvae of the potato tuber moth were introduced to potato seedlings at the seedling stage to induce feeding stress at 12, 24, 36, and 48 h as treatments, with no-stress control. Isolation culture and high-throughput sequencing techniques were used to analyze changes in the community composition and diversity of endophytic bacteria in potato leaves.

Results Potato tuber moth feeding stress altered the endophytic bacterial community composition in potato leaves. After 12, 24, 36, and 48 h of feeding stress, the relative abundance of Firmicutes increased by 21.43%, 8.70%, 27.27%, and 58.53%, respectively; the relative abundance of Actinobacteria increased by 5.00%, 2.50%, 10.00%, and 3.70%, respectively; the relative abundance of Proteobacteria decreased by 66.67%, 28.03%, 55.56%, and 60.05%, respectively. The relative abundance of Staphylococcus increased by 14.57%, 113.87%, 51.44%, and 175.36%, respectively; while that of Bacillus decreased by 8.73%, 57.10%, 40.56%, and 86.65%, respectively; Paracoccus was present in all time points of the control group, while in the treatment group it appeared only at 48 h, showing an 89.75% reduction compared to the control. PICRUSt 1 functional prediction results indicated that after potato tuber moth feeding stress, the metabolic functions of endophytic bacteria in potato leaves showed high-abundance enrichment, primarily involving amino acid and carbohydrate metabolism.

Conclusion Potato tuber moth feeding stress alters the composition and relative abundance of the endophytic bacterial community in potato leaves, enhancing the enrichment of metabolic functions within the leaves.