Molecular Soil Biology 2025, Vol.16, No.2, 73-82 http://bioscipublisher.com/index.php/msb 73 Feature Review Open Access Screening of Disease-Resistant Germplasm and Its Application in Off-Season Cultivation of Leonurus japonicus var. hunanensis Minghui Zhao, Huizhen Huang Tropical Medicinal Plant Research Center, Hainan Institute of Tropical Agricultural Resources, Sanya, 572025, Hainan, China Corresponding email: huizhen.huang@hitar.org Molecular Soil Biology, 2025, Vol.16, No.2 doi: 10.5376/msb.2025.16.0008 Received: 23 Jan, 2025 Accepted: 26 Feb., 2025 Published: 04 Apr., 2025 Copyright © 2025 Zhao and Huang, This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Preferred citation for this article: Zhao M.H., and Huang H.Z., 2025, Screening of disease-resistant germplasm and its application in off-season cultivation of Leonurus japonicus var. hunanensis, Molecular Soil Biology, 16(2): 73-82 (doi: 10.5376/msb.2025.16.0008) Abstract This study focused on screening and using the disease resistant germplasm resources of Leonurus japonicus var. hunanensis, and analyzed its main diseases in detail. Through field observation, common problems such as powdery mildew, downy mildew and root rot were identified, and their incidence and damage degree under off-season cultivation conditions were evaluated. In the process of off-season planting, due to the changes of temperature, humidity and management conditions, diseases are prone to outbreak, especially in warm and humid environment. The research team conducted field surveys in many planting areas and screened out a batch of disease resistant materials with good comprehensive properties. Among the selected materials with high resistance to powdery mildew, some still maintain a low incidence in high humidity environment, reducing the dependence on chemicals, reducing production costs and improving economic benefits. According to the performance of disease resistant materials, the cultivation mode and management methods were further adjusted. The planting density, water supply and fertilizer use were improved, and the planting environment was properly regulated. The use of disease resistant germplasm combined with optimized cultivation techniques can significantly reduce the occurrence of disease and improve the yield and the level of active ingredients of Leonurus japonicus var. hunanensis in off-season production. This not only improves the economic benefits, but also reduces the use of pesticides, helps to achieve the goal of green planting, and provides a reliable basis for the sustainable development of the industry. Keywords Leonurus japonicus var. hunanensis; Disease-resistant germplasm; Off-season cultivation; Molecular marker screening; Disease control 1 Introduction Leonurus japonicus var. hunanensis is a common medicinal plant, which is mainly used for promoting blood circulation, regulating menstruation, relieving pain and other treatments, and has a long history of application in traditional Chinese medicine (Shang et al., 2014; Li et al., 2019; Miao et al., 2019). Because of its high medicinal value and economic benefits, it has become an important object of cultivation and development. In recent years, off-season planting has been considered as a feasible way, which can be planted outside the traditional supply period, solve the problem of off-season supply, increase farmers' income, and meet the continuous demand of the market for medicinal materials (Krishna et al., 2024). However, in the actual planting process, there are many problems with this mode, especially the high frequency of disease (Schreinemachers et al., 2016), which seriously limits the plant growth, resulting in reduced yield, weakened efficacy and damaged economic benefits. In the off-season period, the climate fluctuates greatly, and the high humidity and temperature difference between day and night are obvious. These conditions provide a good environment for the occurrence of diseases. Diseases such as powdery mildew, downy mildew and root rot are more common, and the prevention and control are more difficult (Dahal et al., 2019; Miller et al., 2024). The disease not only affects the normal growth of plants, but also reduces the content of active ingredients such as alkaloids and flavonoids, and reduces the quality of medicinal materials. There are many methods to solve the disease problem, among which the use of resistant germplasm materials is
RkJQdWJsaXNoZXIy MjQ4ODYzNA==