Diversification is a critical direction for fruit breeding. Fruit size and shape are not only key quality traits but also significant manifestations of diversity. Fruit length serves as a primary parameter influencing both fruit size and shape. Melon ( Cucumis melo   L.) is an ideal model crop for studying fruit development, research on regulatory genes and molecular mechanisms underlying fruit length remains limited. Identifying genes that regulate fruit elongation will deepen our understanding of the genetic basis of fruit size and provide theoretical support for germplasm improvement.

Recently,  Horticulture Research  published the study titled " CmFUL1  was potentially involved in fruit elongation in melon" by the melon genetics, breeding, and cultivation team. Using genome-wide association studies (GWAS) and phylogenetic analysis, the team identified CmFUL1 as a candidate gene regulating fruit length, with its expression being highly specific to flowers and ovaries. Transcriptional profiling revealed that the expression levels of CmFUL1  are negatively correlated with fruit length across diverse melon germplasms. Furthermore, CRISPR-Cas9-engineered CR-Cmful1  mutants exhibited elongated fruits, while heterologous overexpression of CmFUL1  in tomatoes resulted in shorter fruits, demonstrating evolutionary conservation of this homologous gene's function. This study elucidates the role of CmFUL1 in regulating melon fruit elongation, expanding genetic resources for improving melon fruit quality and paving the way for targeted breeding strategies.

Figure 1. The mutants and phenotypic analysis of CR-Cmful1  

Lingli Tang, Assistant Research Fellow from the Melon Genetics and Breeding Research Group is the first author of the article, and Guangwei Zhao serves as the corresponding author. Article link: DOI: 10.1093/hr/uhaf138. This research was funded by National Natural Science Foundation of China (32172581), Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences (CAAS-ASTIP-2025-ZFRI), Agriculture Research System of China (CARS-25-2025-G6), the Henan Special Funds for Major Science and Technology (2211001T10400), Henan Province Science and Technology Research Project (252102110298), and International Cooperation projects of Henan Province of Science and Technology (242102520045).

By tanglingli@caas.cn