赤红壤地区森林土壤球囊霉素相关蛋白测定方法  

An improved procedure for glomalin-related soil protein measurement in subtropical forest

作　　者：张静[1,2,3] 唐旭利[1,3] 郑克举[1,2,3] 童琳[1,2,3] 陈红锋[1] 

机构地区：[1]中国科学院华南植物园,广州510650 [2]中国科学院大学,北京100049 [3]中国科学院退化生态系统植被恢复与管理重点实验室,广州510650

出　　处：《生态学杂志》2014年第1期249-258,共10页Chinese Journal of Ecology

基　　金：国家自然科学基金项目(31270499和31170196);中国科学院青年创新促进会资助

摘　　要：球囊霉素是丛枝菌根真菌菌丝产生的一种糖蛋白，被证明具有改善土壤结构、固定土壤中重金属、保护有机碳等重要的生态功能。球囊霉素目前尚无法纯化，一般通过测定球囊霉素相关蛋白（GRSP）来对其定量。由于GRSP测定方法的非专一性，目前尚无适宜于各种陆地生态系统的标准测定方法。本文针对GRSP测定结果可能受到提取时间、离心力以及测定前再次离心时离心力的大小等因素的影响，设置对比试验，对亚热带赤红壤地区土壤GRSP提取测定，以期获取适合于该地区的GRSP测定方法。结果表明：当提取时离心时间为10 min，10000×g的离心力提取的易提取GRSP（EE-GRSP）是5000×g提取的1.15～1.82倍，但离心力大小对总GRSP（T-GRSP）影响不显著；当提取时离心力为5000×g时，离心时间由10 min延长至15 min能够显著提高EE-GRSP含量；测定之前对上清液再次离心，若使用较大的离心力（≥10000×g），将显著影响GRSP测定值；经过6次连续提取，能够提取T-GRSP理论最大含量的97.7%～99.8%；因此，在亚热带酸性赤红壤森林生态系统中，GRSP的提取建议采用10000×g 10 min的离心力和离心时间组合，测定前对上清液再次离心时，应以≥10000×g的离心力为宜，研究结果为该地区GRSP的标准化测定提供了理论依据。Glomalin as a recalcitrant glycoprotein produced by arbuscular mycorrhizal fungi is proved to improve soil structure, fix heavy metals in soils, and be a substantial contributor to soil carbon. At present, glomalin cannot be directly purified but can be quantified by measuring the content of glomalin-related soil protein （GRSP） in soil. Currently no standard procedure for GRSP measurement is available for all terrestrial ecosystems because of the non-specific nature of GRSP measurement. To investigate the possible influences of extraction time, centrifugal force, and centrifugal force before colorimetric test on GRSP measurement, we carried out a comparative study using latosolic red soils collected from a subtropical forest. Higher centrifugal force extracted more easily extractable GRSP （EE-GRSP） for a given centrifuge time. Under 10 minutes of extraction, EEGRSP extracted with centrifugal force at 10000×g was 1.15-1.82 times more than at 5000×g, but the effect of centrifugal force on T-GRSP was not significantly different at α=0.05 level. Extending centrifugal time increased EE-GRSP concentration for a given centrifugal force. With the centrifugal force at 5000×g, EE-GRSP content increased significantly with the increase of centrifugation time from 10 minutes to 15 minutes. Centrifugation of the supernate with higher centrifugal force （≥10000×g） before colorimetric test significantly influenced the measurement of GRSP. The T-GRSP value reached 97.7%-99.8% of the theoretical maximum after 6 times of repeated extraction. Based on this study, the procedure for GRSP measurement for latosolic red soils in subtropical forests is recommended as centrifugation of soil solution at 10000×g for 10 minutes, and centrifugation of the supernate at 10000×g before colorimetric test.

关 键 词：丛枝菌根 球囊霉素相关蛋白 测定方法 亚热带森林 

分 类 号：S714[农业科学—林学]