Autotoxicity of Phthalate Esters in Tobacco Root Exudates：Effects on Seed Germination and Seedling Growth

• Published in: Pedosphere Vol. 27; no. 6; pp. 1073 - 1082
• Main Authors: DENG, Jiajun, ZHANG, Yanling, HU, Jiwei, JIAO, Jiaguo, HU, Feng, LI, Huixin, ZHANG, Shixiang
• Format: Journal Article
• Language: English
• Published: Beijing Elsevier Ltd 01.12.2017; Elsevier Science Ltd; Soil Ecology Laboratory, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095(China); Testing Center of Agro-Product Quality and Safety of Jiangxi Province, Nanchang 330046(China)%Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou 450001(China); Key Laboratory of Eco-Environmental and Tobacco Leaf Quality of CNTC, Zhengzhou 450001(China)%Guizhou Provincial Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, Guiyang 550001(China)%Soil Ecology Laboratory, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095(China)
• Subjects: autotoxins; Continuous cropping; Dibutyl phthalate; Dioctyl phthalate; Esters; Exudates; Exudation; Germination; germination index; germination potential; germination rate; Liquid chromatography; Mass spectrometry; Mass spectroscopy; Organic chemistry; Phthalate esters; Plant growth; Quadrupoles; Seed germination; Seedlings; Seeds; Tobacco; Vigor; vigor index; vigor index; germination index; germination rate; autotoxins; germination potential
• ISSN: 1002-0160; 2210-5107
• DOI: 10.1016/S1002-0160(17)60374-6

Autotoxicity is one of the major factors that impede continuous cropping.It is defined as the toxic influence of chemicals released from one plant species on the germination and growth of individuals of the same species.Here, in order to exam the autotoxicity of tobacco root exudates, root exudates were collected from tobacco plants grown both in cultural solution and on natural soil.Using ultraperformance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry, main autotoxic chemical substances in the root exudates were identified.The autotoxic effects of suspected autotoxins on seed germination（including germination rate,germination potential, germination index, and vigor index） and seedling growth were analyzed.Dibutyl phthalate（or diisobutyl phthalate）, dioctyl phthalate, and diisooctyl phthalate were identified in tobacco root exudates.It was observed that high concentrations（greater than 0.5 mmol L~（-1）） of each identified phthalate ester caused significant（P 〈 0.05） inhibition of tobacco seed germination and seedling growth.It can be concluded that phthalate esters such as dibutyl phthalate, diisobutyl phthalate, and diisooctyl phthalate in tobacco root exudates may play an important role in tobacco autotoxicity.