Yang Ruixue, Sun Zhengguo, Liu Xinbao, Long Xiaohua, Gao Limin, Shen Yixin
College of Agro-grassland Science, Nanjing Agricultural University, Nanjing, China.
College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China.
Front Plant Sci. 2023 Mar 28;14:1163195. doi: 10.3389/fpls.2023.1163195. eCollection 2023.
In coastal saline lands, organic matter is scarce and saline stress is high. Exploring the promotion effect of intervention with organic acid from biological materials on soil improvement and thus forage output and determining the related mechanism are beneficial to the potential cultivation and resourceful, high-value utilization of coastal mudflats as back-up arable land.
Three exogenous organic acids [humic acid (H), fulvic acid (F), and citric acid (C)] were combined with four kinds of biomass materials [cottonseed hull (CH), cow manure (CM), grass charcoal (GC), and pine needle (PN)] and applied to about 0.3% of medium-salt mudflat soil. The salinity and nutrient dynamics of the soil and the growth and physiological differences of sweet sorghum at the seedling, elongation, and heading stages were observed under different treatments to screen for efficient combinations and analyze the intrinsic causes and influencing mechanisms.
The soil salinity, nutrient dynamics, and forage grass biological yield during sweet sorghum cultivation in saline soils differed significantly ( < 0.05) depending on the type of organic acid-biomass composite applied. Citric acid-pine needle composite substantially reduced the soil salinity and increased the soil nutrient content at the seedling stage and improved the root vigor and photosynthesis of sweet sorghum by increasing its stress tolerance, allowing plant morphological restructuring for a high biological yield. The improvement effect of fulvic acid-pine needle or fulvic acid-cow manure composite was manifested at the elongation and heading stages.
Citric acid-pine needle composite promoted the growth of saline sweet sorghum seedlings, and the effect of fulvic acid-pine needle composite lasted until the middle and late stages.
在沿海盐碱地，有机质稀缺且盐胁迫严重。探索生物材料中的有机酸干预对土壤改良及饲草产量的促进作用，并确定相关机制，有利于将沿海滩涂作为后备耕地进行潜在耕种和资源化、高价值利用。
将三种外源有机酸[腐殖酸（H）、黄腐酸（F）和柠檬酸（C）]与四种生物质材料[棉籽壳（CH）、牛粪（CM）、草炭（GC）和松针（PN）]组合，施用于约0.3%的中盐度滩涂土壤。观察不同处理下土壤的盐分和养分动态以及甜高粱在苗期、拔节期和抽穗期的生长和生理差异，以筛选高效组合并分析内在原因和影响机制。
盐碱地甜高粱种植过程中的土壤盐分、养分动态和饲草生物产量因施用的有机酸 - 生物质复合材料类型不同而有显著差异（<0.05）。柠檬酸 - 松针复合材料在苗期显著降低了土壤盐分，提高了土壤养分含量，并通过提高甜高粱的抗逆性改善了其根系活力和光合作用，使植株形态重构以实现高生物产量。黄腐酸 - 松针或黄腐酸 - 牛粪复合材料的改良效果在拔节期和抽穗期显现。
柠檬酸 - 松针复合材料促进了盐碱地甜高粱幼苗的生长，黄腐酸 - 松针复合材料的效果持续到中后期。
