Plant–endophytic fungi are widely distributed and highly diverse, with many of them capable of influencing plant growth and development, which is related to the production of volatile organic compounds (VOCs). While certain fungal VOCs have been found to stimulate plant growth, others exhibit inhibitory effects. Importantly, the impact of fungal VOCs extends beyond host plants to affect non-host plants as well. In this study, we isolated two plant–endophytic fungi, Clonostachys sp. CC1 and Clonostachys sp. CC2, from healthy rice roots. These strains were co-cultured with both rice and Arabidopsis thaliana. Our results demonstrated that both strains significantly enhanced the growth of both rice and A. thaliana. Specifically, they increased the length and biomass of rice and A. thaliana seedlings, as well as the chlorophyll content, while decreasing the H₂O₂ content in the leaves of both plants. The VOCs produced by these strains were analyzed using gas chromatography–mass spectrometry (GC-MS), which identified a total of 10 main ingredients. Among these compounds, 1-pentanol, ethylbenzene, and dimethyl phthalate inhibited the growth of rice while promoting the growth of A. thaliana, highlighting the variability in the effects of these compounds on different plant species and the complexity of plant–fungal interactions.

The Chinese flowering cherry (Cerasus serrulata), an ornamental tree with established medicinal values, is observed to suffer from leaf blight within Xi’an’s greenbelts. This disease threatens both the plant’s growth and its ornamental appeal. In this study, 26 isolates were obtained from plants with typical leaf blight, and only 3 isolates (XA-10, XA-15, and XA-18) were found to be pathogenic, causing similar symptoms on the leaves of the host plant. Based on sequence alignment, the ITS and LSU sequences of the three selected isolates were consistent, respectively. Following morphological and molecular analyses, the three selected isolates were further identified as Mortierella alpina. The three selected isolates exhibited similar morphological characteristics, including wavy colonies with dense, milky-white aerial mycelia on PDA medium. Therefore, isolate XA-10 was used as a representative strain for subsequent experiments. The representative strain XA-10 was found to exhibit optimal growth at a temperature of 30 °C and a pH of 7.0. Host range infection tests further revealed that the representative strain XA-10 could also inflict comparable disease symptoms on both the leaves and fruits of three different Rosaceae species (Prunus persica, Pyrus bretschneideri, and Prunus salicina). This study reveals, for the first time, the causative agent of leaf blight disease affecting the Chinese flowering cherry. This provides a deeper understanding of the biology and etiology of M. alpina. This study lays a solid foundation for the sustainable control and management of leaf blight disease in the Chinese flowering cherry.

Plant endophytic fungi, which colonize plant tissues and form symbiotic relationships with their hosts, are known for their high diversity and wide distribution. These fungi often influence plant growth and development through the emission of volatile organic compounds (VOCs), whose effects can extend beyond host plants to non-host species. In this study, we isolated two endophytic fungi, Trametes hirsuta RR1 and Talaromyces pinophilus RR2 from healthy rice roots. The VOCs mixtures produced by strains RR1 and RR2 were both able to promote rice growth when these strains were co-cultured with rice seedlings. Specifically, strain RR1 and RR2 increased rice shoot fresh weight by 44.22% and 26.69%, root fresh weight by 58.24% and 41.76%, shoot length by 30.35% and 25.07%, and root length by 29.11% and 4.23%, respectively. They significantly enhanced the contents of chlorophyll a and carotenoids, which increased by 18.61% and 17.04%, and by 18.73% and 31.55%, respectively. Gas chromatography–mass spectrometry (GC-MS) was applied to analyze the VOCs emitted by the two strains. The analysis successfully identified a total of 13 major compounds. Among them, at appropriate concentrations, 1-pentanol, methyl DL-2-methylbutyrate, ethylbenzene, 2-ethyl-p-xylene, ethyl benzoate and dimethyl phthalate, can promote rice growth and alter the contents of photosynthetic pigments and hydrogen peroxide to varying degrees. This study provides an important basis for the in-depth research and development of biofumigants for promoting crop growth.