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Summary: The plant hormone ethylene plays a critical role in fruit defense against Botrytis cinerea attack, but the underlying mechanisms remain poorly understood. Here, we showed that ethylene response factor SlERF.C1 acts as a key regulator to trigger the ethylene‐mediated defense against B. cinerea in tomato fruits without compromising ripening.Knockout of SlERF.C1 increased fruit susceptibility to B. cinerea with no effect on ripening process, while overexpression enhanced resistance. RNA‐Seq, transactivation assays, EMSA and ChIP‐qPCR results indicated that SlERF.C1 activated the transcription of PR genes by binding to their promoters.Moreover, SlERF.C1 interacted with the mitogen‐activated protein kinase SlMPK8 which allowed SlMPK8 to phosphorylate SlERF.C1 at the Ser174 residue and increases its transcriptional activity. Knocking out of SlMPK8 increased fruit susceptibility to B. cinerea, whereas overexpression enhanced resistance without affecting ripening. Furthermore, genetic crosses between SlMPK8‐KO and SlERF.C1‐OE lines reduced the resistance to B. cinerea attack in SlERF.C1‐OE fruits. In addition, B. cinerea infection induced ethylene production which in turn triggered SlMPK8 transcription and enhanced the phosphorylation of SlERF.C1.Overall, our findings reveal the regulatory mechanism of the 'Ethylene‐MPK8‐ERF.C1‐PR' module in resistance against B. cinerea and provide new insight into the manipulation of gray mold disease in fruits. [ABSTRACT FROM AUTHOR]

SUMMARY: The presence or absence of spines is an important economic trait of cucumber fruit. Spines are believed to be a type of specialized trichome on the fruit surface, and all the identified cucumber trichome‐less mutants lack fruit spines. However, genes that specifically regulate fruit spine initiation remain to be identified. Here, we found that knocking out cucumber TARGET OF EAT3 homolog (CsTOE3), belonging to the APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF) family, affected flower development and, more interestingly, inhibited cucumber fruit spine initiation. On analyzing expression patterns by quantitative reverse transcriptase‐polymerase chain reaction and in situ hybridization assay, CsTOE3 was found to be highly expressed in male and female flowers, and its mRNA accumulated in the tips of sepal and petal primordia and in the cells of fruit spines and peels. Biochemical analyses indicated that CsTOE3 directly interacts with GLABRA1 (CsGL1) and TRANSPARENT TESTA GLABRA1 (CsTTG1), which are positive regulators of trichome formation. In addition, RNA‐seq showed that the transcription levels of eight ERFs were significantly upregulated in CsTOE3 knockout lines. Phytohormone content analysis also revealed a significant increase in the amount of ethylene released by CsTOE3 knockout line, and treatment with the ethylene synthesis inhibitor aminoethoxyvinyl‐glycine partly restored the spineless phenotype. Our results suggest that CsTOE3 specifically regulates fruit spine initiation but does not affect the formation of trichomes on other organs in cucumber. Our findings may have a far‐reaching significance for cucumber germplasm improvement and quality breeding using fruit spines as the target trait. Significance Statement: Trichomes on cucumber fruits are commonly called fruit spines, which directly affect the appearance and perceived quality of the fruits. Here, we found that knocking out CsTOE3 inhibited fruit spine initiation but had no effects on trichome formation in other plant parts, providing a new insight into the formation of cucumber fruit spines. [ABSTRACT FROM AUTHOR]

The eggplant (Solanum melongena L.) is one of the most important Solanaceae crops, ranking third for total production and economic value in its genus. Herein, we report a high‐quality, chromosome‐scale eggplant reference genome sequence of 1155.8 Mb, with an N50 of 93.9 Mb, which was assembled by combining PacBio long reads and Hi‐C sequencing data. Repetitive sequences occupied 70.1% of the assembly length, and 35,018 high‐confidence protein‐coding genes were annotated based on multiple sources. Comparative analysis revealed 646 species‐specific families and 364 positive selection genes, conferring distinguishing traits on the eggplant. We performed genome‐wide comparative identification of disease resistance genes and discovered an expanded gene family of bacterial spot resistance in eggplant and pepper, but not in tomato and potato. The genes involved in chlorogenic acid synthesis were comprehensively characterized. Highly similar chromosomal distribution patterns of polyphenol oxidase genes were observed in the eggplant, tomato, and potato genomes. The eggplant reference genome sequence will not only facilitate evolutionary studies of the Solanaceae but also facilitate their breeding and improvement. [ABSTRACT FROM AUTHOR]