Fallah Nyumah, Pang Ziqin, Lin Zhaoli, Nyimbo Witness Joseph, Lin Wenxiong, Mbuya Sylvain Ntambo, Ishimwe Captoline, Zhang Hua
Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, China.
Fujian Provincial Key Laboratory of Agro-ecological Processing and Safety Monitoring, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China.
Front Plant Sci. 2023 Sep 18;14:1273546. doi: 10.3389/fpls.2023.1273546. eCollection 2023.
Organic soil amendments such as filter mud (FM) and biochar (BC) can potentially influence the abundance and composition of metabolites. However, our current understanding of the stimulatory effects of FM and BC's long-term impact on stress-regulating metabolites, such as abscisic acid (ABA), jasmonic acid (JA), melatonin, and phenyllactic acid (PLA), and these substrates regulatory effects on disease-causing bacteria in sugarcane ratooning field, which is susceptible to nutrients depletion, diseases, etc., remain poorly understood. Additionally, little is known about how the long-term interaction of these substrates and compounds influences sugarcane ratooning soil enzyme activities, nutrient cycling, and crop growth performance.
To answer these questions, we adopted metabolomics tools combined with high-throughput sequencing to explore the stimulatory effects of the long-term addition of FM and BC on metabolites (e.g., PLA and abscisic aldehyde) and quantify these substrates' regulatory effects on disease-causing bacteria, soil enzyme activities, nutrient cycling, and crop growth performance.
The result revealed that ratoon crop weight, stem diameter, sugar content, as well as soil physico-chemical properties, including soil nitrate (NH -N), organic matter (OM), total nitrogen (TN), total carbon (TC), and β-glucosidase, marked a significant increase under the BC and FM-amended soils. Whereas soil available potassium (AK), NO N, cellulase activity, and phosphatase peaked under the BC-amended soil, primarily due to the enduring effects of these substrates and metabolites. Furthermore, BC and FM-amended soils enriched specific stress-regulating metabolites, including JA, melatonin, abscisic aldehyde, etc. The sustained effects of both BC and FM-amended soils suppressed disease-causing bacteria, eventually promoting ratooning soil growth conditions. A number of key bioactive compounds had distinct associations with several beneficial bacteria and soil physico-chemical properties.
This study proves that long-term BC and FM application is one of the eco-friendly strategies to promote ratoon crop growth and soil quality through the enrichment of stress-regulating metabolites and the suppression of disease-causing bacteria.
滤泥（FM）和生物炭（BC）等有机土壤改良剂可能会影响代谢物的丰度和组成。然而，我们目前对滤泥和生物炭对胁迫调节代谢物（如脱落酸（ABA）、茉莉酸（JA）、褪黑素和苯乳酸（PLA））的刺激作用，以及这些底物对宿根甘蔗田致病细菌的调节作用了解甚少，宿根甘蔗田易出现养分耗尽、病害等问题。此外，对于这些底物和化合物的长期相互作用如何影响宿根甘蔗土壤酶活性、养分循环和作物生长性能，人们所知甚少。
为回答这些问题，我们采用代谢组学工具结合高通量测序，探究长期添加滤泥和生物炭对代谢物（如苯乳酸和脱落醛）的刺激作用，并量化这些底物对致病细菌、土壤酶活性、养分循环和作物生长性能的调节作用。
结果表明，在添加生物炭和滤泥改良的土壤中，宿根作物重量、茎直径、含糖量以及土壤理化性质，包括土壤硝态氮（NH₄⁺-N）、有机质（OM）、总氮（TN）、总碳（TC）和β-葡萄糖苷酶，均显著增加。而土壤速效钾（AK）、NO₃⁻-N、纤维素酶活性和磷酸酶在添加生物炭改良的土壤中达到峰值，这主要归因于这些底物和代谢物的持久作用。此外，添加生物炭和滤泥改良的土壤中富集了特定的胁迫调节代谢物，包括茉莉酸、褪黑素、脱落醛等。添加生物炭和滤泥改良的土壤的持续作用抑制了致病细菌，最终改善了宿根土壤的生长条件。许多关键生物活性化合物与几种有益细菌和土壤理化性质有着明显的关联。
本研究证明，长期施用生物炭和滤泥是一种生态友好型策略，可通过富集胁迫调节代谢物和抑制致病细菌来促进宿根作物生长和改善土壤质量。
