Wheat stem rust is one of the wheat diseases caused by Puccinia graminis Pers. f. sp. tritici (Pgt). This disease has been responsible for major losses to wheat production worldwide. Currently used methods for controlling this disease include fungicides, the breeding of stem rust-resistant cultivars, and preventive agricultural measures. However, the excessive use of fungicides can have various deleterious effects on the environment. A hyperparasitic fungus with white mycelia and oval conidia, Simplicillium lanosoniveum, was isolated from the urediniospores of Pgt. When Pgt-infected wheat leaves were inoculation with isolates of S. lanosoniveum, it was found that S. lanosoniveum inoculation inhibited the production and germination of urediniospores, suggesting that S. lanosoniveum could inhibit the growth and spread of Pgt. Scanning electron microscopy revealed that S. lanosoniveum could inactivate the urediniospores by inducing structural damage. Overall, findings indicate that S. lanosoniveum might provide an effective biological agent for the control of Pgt.

Puccinia graminis f. sp. tritici (Pgt) is responsible for stem rust in wheat, a disease with worldwide occurrence. Ethylene response factors (ERFs), a group of transcription factors (TFs) responsive to ethylene, are essential for managing stress signaling under biotic and abiotic challenges. However, our understanding of ERF TFs’ function in wheat (Triticum aestivum L.) resistance against the obligate biotrophic Puccinia graminis f. sp. tritici remains limited. In this work, we report our findings of the TaERF109 gene, which is transcriptionally up-regulated by ethylene or Pgt infection. TaERF109 is localized in the nucleus of rice protoplasts. Results obtained using the yeast one-hybrid (Y1H) assay support the conclusion that TaERF109 interacts with the AGCCGCC sequence (GCC-box). Transient knockdown of TaERF109 via virus-induced gene silencing (VIGS) increased wheat susceptibility to Pgt, accompanied by the down-regulation of three pathogenesis-related (PR) genes, TaPR1, TaPR2, and TaPR10, as confirmed via real-time quantitative PCR. In contrast, the Agrobacterium-mediated overexpression of TaERF109 potentiated resistance of transgenic wheat against Pgt. Overall, these results expand the current understanding of the TaERF109 gene’s function in wheat resistance to Pgt.

Ammopiptanthus mongolicus is a rare tertiary relic evergreen broad-leaved shrub that is seriously threatened by Fusarium wilt disease caused by Fusarium verticillioides. Mycorrhiza is a widely occurring symbiotic association of plant roots with arbuscular mycorrhizal fungi. To explore the relationship between wilt disease in A. mongolicus and arbuscular mycorrhiza, fungal communities in the roots and rhizosphere of healthy and diseased plants were analyzed using high-throughput sequencing technology based on specific primer amplicons. Arbuscular mycorrhizal fungal communities in roots were more strongly affected by Fusarium wilt disease than those in the rhizosphere. Wilt disease had no effect on α-diversity indices (Shannon and Simpson) in both the roots and rhizosphere soil, or on the phylogenetic diversity index (Pd) and richness indices (Chao, Ace and Sobs) in rhizosphere soil. However, it had a significant effect on the phylogenetic diversity index (Pd) and richness indices (Chao and Sobs) of arbuscular mycorrhizal fungal communities in the roots. Wilt disease increased the abundance of the genus Sclerocystis and decreased the abundance of Glomus. Arbuscular mycorrhizal fungal communities in diseased plants showed greater co-occurrence network complexity in both rhizosphere soil and roots. In terms of the ecological processes driving arbuscular mycorrhizal fungal community assembly, drift was intensified by wilt disease in both rhizosphere soil and roots. This study revealed the effect of wilt disease on arbuscular mycorrhizal fungal communities in the rhizosphere soil and roots of A. mongolicus. These findings provide important theoretical support and core AMF resources for the ecological prevention and control of A. mongolicus wilt disease.