A Systematic Review on the Continuous Cropping Obstacles and Control Strategies in Medicinal Plants

Abstract

Continuous cropping (CC) is a common practice in agriculture, and usually causes serious economic losses due to soil degeneration, decreased crop yield and quality, and increased disease incidence, especially in medicinal plants. Continuous cropping obstacles (CCOs) are mainly due to changes in soil microbial communities, nutrient availability, and allelopathic effects. Recently, progressive studies have illustrated the molecular mechanisms of CCOs, and valid strategies to overcome them. Transcriptomic and metabolomics analyses revealed that identified DEGs (differently expressed genes) and metabolites involved in the response to CCOs are involved in various biological processes, including photosynthesis, carbon metabolism, secondary metabolite biosynthesis, and bioactive compounds. Soil improvement is an effective strategy to overcome this problem. Soil amendments can improve the microbial community by increasing the abundance of beneficial microorganisms, soil fertility, and nutrient availability. In this review, we sum up the recent status of the research on CCOs in medicinal plants, the combination of transcriptomic and metabolomics studies, and related control strategies, including uses of soil amendments, crop rotation, and intercropping. Finally, we propose future research trends for understanding CCOs, and strategies to overcome these obstacles and promote sustainable agriculture practices in medicinal plants.

Effect of Cucumber Continuous Monocropping on Traditional Chinese Medicine Residue through Analysis of Physicochemical Characteristics and Microbial Diversity

“…The main obstacles posed by continuous cropping is the decrease in soil quality, which can include soil compaction, nutrient imbalance, salinization, enzyme activity reduction, and the accumulation of harmful microorganisms [48]. In our study, the physiochemical property indices of the substrates (EC, and OM, TN and TP contents) decreased with continuous cropping.…”

A Genome-Wide Identification and Expression Analysis of the Casparian Strip Membrane Domain Protein-like Gene Family in Pogostemon cablin in Response to p-HBA-Induced Continuous Cropping Obstacles

“…In agricultural practice, the continuous planting of P. cablin on the same land will lead to changes in the soil's physical and chemical properties [52,53], the microbial community structure, the aggravation of soil diseases, and more serious allelopathic autotoxicity, resulting in serious continuous cropping obstacles [54][55][56][57]. Previous studies have found that p-HBA is the main allelochemical that induces continuous cropping obstacles of P. cablin [16,58]. In this study, 30 down-regulated candidate genes and 27 up-regulated candidate genes were identified by analyzing the transcriptome data of P. cablin roots treated with p-HBA.…”

Effects of Exogenous Organic Acids on the Soil Metabolites and Microbial Communities of Panax notoginseng from the Forest Understory

“…Moreover, the mixed organic acids also increased the content of L-malic and shikimic acid in the biosynthesis of the plant hormones pathway. Previous results have shown that L-malic and shikimic acid could promote the growth of pathogens and the formation of phenolic acid autotoxic substances [3,48,49], respectively. Therefore, the mixed organic acids increased the production of harmful metabolites in Sanqi soil, resulting in the autotoxicity of the mixed organic acids being stronger than that of the single organic acids.…”