Sweet potato (Ipomoea batatas (L.) Lam.) is one of the most important food, feed, industrial raw materials, and new energy crops, and is widely cultivated around the world. China is the largest sweet potato producer in the world, and the sweet potato industry plays an important role in China’s agriculture. During the growth of sweet potato, it is often affected by biotic stresses, such as fungi, nematodes, insects, viruses, and bacteria. These stressors are widespread worldwide and have severely restricted the production of sweet potato. In recent years, with the rapid development and maturity of biotechnology, an increasing number of stress-related genes have been introduced into sweet potato, which improves its quality and resistance of sweet potato. This paper summarizes the discovery of biological stress-related genes in sweet potato and the related mechanisms of stress resistance from the perspectives of genomics analysis, transcriptomics analysis, genetic engineering, and physiological and biochemical indicators. The mechanisms of stress resistance provide a reference for analyzing the molecular breeding of disease resistance mechanisms and biotic stress resistance in sweet potato.

Castanea henryi is a ubiquitous hardwood chestnut species in southern China and is important both ecologically and economically. It is mainly cultivated for nut production, just like other chestnut species. However, the establishment of C. henryi seedlings in a new orchard has proven to be difficult because few seedlings survive transplanting due to the incompatibility of their coarse root architecture with nutrient-depleted red acid soils in southern China. Root architecture can be profoundly modified and nutrient can be stress alleviated due to the association of roots with ectomycorrhizal (ECM) fungi. Boletus edulis is an ECM fungus with edible and medicinal fruiting bodies. However, its impact on plant growth varies with the plant species it is associated with. In order to elucidate the role of B. edulis in C. henryi afforestation, we evaluated growth parameters and soil enzymatic activities, as well as seasonal variations in physiology and structure of ECM root tips. Growth responses and soil enzymatic activities were measured 6 months after inoculation. The physiological characteristics of root tips were also compared at various seasons throughout the year. B. edulis colonization of C. henryi roots was successful at a 60% colonization rate. Height, base diameter, and biomass (especially the underground part) of inoculated seedlings (JG) were higher than those of uninoculated seedlings (CK). JG had higher root total length, root surface area, root volume, root average diameter, and number of root tips than CK. Additionally, JG exhibited higher total nitrogen and phosphorus content. Abnormal mantle and Harting net were observed in winter. No matter the season, ECM tips had higher antioxidant enzyme activities, root activities, soluble protein content, and lower malondialdehyde compared to non-ECM tips (nE) and those without ECM tips (woE), and there were no differences between nE and woE. It is important to understand the growth of the host plant in response to ECM and that the seasonal variation of ECM root tips is important when growing high-quality C. henryi seedlings, due to the crucial role of B. edulis in improving seedling initial survival rate.

Summary: The stem nematode (Ditylenchus destructor Thorne) is a pervasive and destructive plant‐parasitic nematode worldwide, inflicting severe agricultural and economic losses in a wide range of crops. Despite its global impact, the molecular mechanisms underlying plant resistance to this pathogen remain poorly understood. Our previous studies in sweet potato (Ipomoea batatas L.) identified IbPIF1 as one of the most strongly induced genes following stem nematode infection, positioning it as a key candidate for unravelling host defence strategies. In this study, we revealed that overexpression of IbPIF1 not only activates systemic immunity and strengthens physical barrier functions, but also drives the accumulation of phytoalexins, significantly enhancing nematode resistance in transgenic plants. Furthermore, IbPIF1 enhances the accumulation of defensive compounds, including lignin, callose and terpenoids, which are vital for the resilience of plants against stem nematode infection. Intriguingly, genetic and molecular analysis shows that IbMVD, a pivotal gene in the regulation of terpenoid synthesis, operates downstream of IbPIF1 in this defence network. Specifically, IbPIF1 directly binds to the promoter of IbMVD, inducing its expression and thereby modulating terpenoid‐mediated resistance. These results suggest that IbPIF1 plays a pivotal regulatory role in a complex transcriptional network controlling the stem nematode response. This work advances our understanding of plant‐nematode interactions and opens avenues for engineering nematode‐resistant crops through genetic manipulation.

Background/Objectives: GATA transcription factors play pivotal roles in regulating plant growth and development, physiological metabolism, and responses to environmental stress. However, research on GATA genes in sweetpotato remains limited. Methods: In this study, we identified 25 IbGATA genes in sweetpotato (Ipomoea batatas [Lam.] L.) through a genome-wide analysis. These genes were analyzed for their physicochemical properties, chromosomal localization, synteny, phylogenetic relationships, gene structure, promoter cis-elements, protein interaction networks, and expression profiles across various tissues and under drought stress. To elucidate the function of drought-resistant candidate genes, an in situ one-step transformation method was employed. Results: Sweetpotato GATA genes have a complex evolutionary history, including replication events, different selection pressures, and functional diversification. They may be involved in multiple plant stress signaling pathways. Furthermore, functional analysis revealed that IbGATA17 enhances drought tolerance in sweetpotato by promoting proline biosynthesis and reinforcing ROS scavenging capacity. Our findings provide novel insights into the roles of IbGATAs, particularly IbGATA17, in mediating drought-stress responses in sweetpotato. Conclusions: This study provides foundational insights into the GATA gene family in sweetpotato and reveals the pivotal role of IbGATA17 in simulated drought-stress response, providing a potential candidate gene for the development of drought-resistant varieties.