Molecules 2011, 16, 8874-8893; doi:10.3390/molecules16108874 OPEN ACCESS molecules ISSN 1420-3049 www.mdpi.com/journal/molecules Article Autotoxicity and Allelopathy of 3,4-Dihydroxyacetophenone Isolated from Picea schrenkiana Needles Xiao Ruan 1,2, Zhao-Hui Li 2, Qiang Wang 2,4,*, Cun-De Pan 3, De-An Jiang 1,* and G. Geoff Wang 4 1 College of Life Science, Zhejiang University, Hangzhou, 310058, China 2 Ningbo Institute of Technology, Zhejiang University, Ningbo, 315100, China 3 College of Forestry, Xinjiang Agricultural University, Urumqi, 830052, China 4 Department of Forestry and Natural Resources, Clemson University, 261 Lehotsky Hall, Clemson, SC 29634, USA * Authors to whom correspondence should be addressed; E-Mails:
[email protected] (Q.W.);
[email protected] (D.-A.J.); Tel.: +86-574-88134338 (Q.W.); +86-571-88206461 (D.-A.J.); Fax: +86-574-88229545(Q.W.). Received: 19 September 2011; in revised form: 9 October 2011 / Accepted: 17 October 2011 / Published: 24 October 2011 Abstract: Bioassay-guided fractionation of the diethyl ether fraction of a water extract of Picea schrenkiana needles led to the isolation of the phenolic compound 3,4-dihydroxy- acetophenone (DHAP). The allelopathic effects of DHAP were evaluated under laboratory conditions on P. schrenkiana, rice (Oryza sativa L.), wheat (Triticum aestivum L.), radish (Raphanus sativus L.), lettuce (Latuca sativa L.), cucumber (Cucumis sativus L.) and mung bean (Phaseolus radiatus L.). DHAP significantly inhibited seed germination and seedling growth of P. schrenkiana at concentrations of 2.5 mM and 0.5 mM (p < 0.05). Soil analysis revealed that P. schrenkiana forest soils contained exceptionally high DHAP concentrations (mean = 0.51 ± 0.03 mg/g dry soil), sufficient to inhibit natural P.