WRKY genes and jasmonic acid (JA) play a crucial role in plants’ responses against biotic and abiotic stress. However, the regulating mechanism of WRKY genes on strawberry fruits’ resistance against Botrytis cinerea is largely unknown, and few studies have been performed on their effect on the JA-mediated defense mechanism against B. cinerea. This study explored the effect of FaWRKY25 on the JA-mediated strawberry resistance against B. cinerea. Results showed that the JA content decreased significantly as the fruits matured, whereas the FaWRKY25 expression rose substantially, which led to heightened susceptibility to B. cinerea and in strawberries. External JA treatment significantly increased the JA content in strawberries and reduced the FaWRKY25 expression, thereby enhancing the fruits’ resistance against B. cinerea. FaWRKY25 overexpression significantly lowered the fruits’ resistance against B. cinerea, whereas FaWRKY25 silencing significantly increased resistance. Moreover, FaWRKY25 overexpression significantly lowered the JA content, whereas FaWRKY25 silencing significantly increased it. FaWRKY25 expression level substantially affects the expression levels of genes related to JA biosynthesis and metabolism, other members of the WRKY family, and defense genes. Accordingly, FaWRKY25 plays a crucial role in regulating strawberries’ resistance against B. cinerea and may negatively regulate their JA-mediated resistance mechanism against B. cinerea.

The ABA receptor pyrabactin resistance 1-like (PYR/PYL) protein family is among the key regulators of plant growth and development, participating in ABA signaling. However, information on this family in strawberry (Fragaria × ananassa), an important fleshy fruit crop worldwide, is limited. In the present work, seven homologs of Arabidopsis PYL were first identified and characterized from Fragaria × ananassa. Furthermore, a comprehensive analysis of the FaPYLs was performed, including their phylogenetic relationships, gene structures, chromosomal locations, and conserved domains. The qRT–PCR analysis showed that FaPYL genes had differential expression patterns between fruit ripening stages, and most of them were transcribed in the SG (small green fruits,) and Wh (white fruits) stages of fruit ripening. Treatment of strawberry fruits with ABA and JA changed the expression of all FaPYLs in a gene-specific manner, depending on the berry ripening stage; at the turning stage, only the expression levels of FaPYL3 and FaPYL4 increased in response to ABA. Promoter analysis showed that most FaPYL genes contain cis-acting elements that respond to stress, light, and phytohormones and are associated with tissue-specific expression. Additionally, FaPYL3 and FaPYL4 were further functionally characterized using transient expression technology. Overexpression of FaPYL3 and FaPYL4 promoted strawberry fruit ripening, which positively regulated FaSnRK2.2 and FaNCED1 transcripts. Our results highlight the great potential of FaPYL genes in breeding genetically modified strawberry varieties with accelerated fruit ripening.

Plant-endophytic microbes affect plant growth, development, nutrition, and resistance to pathogens. However, how endophytic microbial communities change in different strawberry plant compartments after Fusarium pathogen infection has remained elusive. In this study, 16S and internal transcribed spacer rRNA amplicon sequencing were used to systematically investigate changes in the bacterial and fungal diversity and composition in the endophytic compartments (roots, stems, and leaves) of healthy strawberries and strawberries with Fusarium wilt, respectively. The analysis of the diversity, structure, and composition of the bacterial and fungal communities revealed a strong effect of pathogen invasion on the endophytic communities. The bacterial and fungal community diversity was lower in the Fusarium-infected endophytic compartments than in the healthy samples. The relative abundance of certain bacterial and fungal genera also changed after Fusarium wilt infection. The relative abundance of the beneficial bacterial genera Bacillus, Bradyrhizobium, Methylophilus, Sphingobium, Lactobacillus, and Streptomyces, as well as fungal genera Acremonium, Penicillium, Talaromyces, and Trichoderma, were higher in the healthy samples than in the Fusarium wilt samples. The relative abundance of Fusarium in the infected samples was significantly higher than that in the healthy samples, consistent with the field observations and culture isolation results for strawberry wilt. Our findings provide a theoretical basis for the isolation, identification, and control of strawberry wilt disease.