Journal of International Scientific Publications: Agriculture and Food Volume 2, ISSN 1314-8591 (Online), Published at: http://www.scientific-publications.net IN VITRO EFFICACY OF SOME PLANT EXTRACTS AGAINST DAMPING OFF DISEASE OF TOMATOES Steliana Rodino 1,2 , Alina Butu 2 , Marian Butu 2* , Calina Petruta Cornea 1 1 University of Agronomic Sciences and Veterinary Medicine, Bucharest, Romania 2 National Institute of Research and Development for Biological Sciences, Bucharest, Romania Abstract Plant diseases control represent a major challenge that farmers are facing in the management of cropping systems. Rhizoctonia solani is a soilborne fungal pathogen causing tomato (Solanum lycopersicum) root-rot and damping off, and generating compromised quality of crops and reducing yields. Ethanol extracts of five medicinal plants, marigold (Tagetes patula), horsetail (Equisetum arvense), elderberry (Sambucus nigra), burdock (Arctium lappa), liquorice (Glycyrrhiza glabra) were investigated to determine their antifungal potential against Rhizoctonia. Solani. In vitro testing demonstrated a high growth inhibition of the extracts. Four of the extracts totally inhibited the mycelial growth of R. solani compared to the untreated control, at 10% concentration in growth media. For all plant extracts considered, the growth inhibition increased with the concentration of each extract. The obtained results support an interesting direction of research, meaning the use of plant extracts in controlling diseases attacking economically important crops for integrated pest management programmes. Key words: antifungal effect, ethanol plant extracts, Rhizoctonia solani, damping off tomatoes 1. INTRODUCTION Taking into consideration the demands of a growing population, food production must rise by 70% by 2050 to feed nine billion people (FAO statistics). Food and beverages industry and commerce are dependent on agricultural sector as their main supplier of raw materials. The challenge is to provide more output with limited resources available. Plant diseases control represent a major issue that farmers are facing in the management of cropping systems. The fungal diseases represent one of the major cause of decreased yields of agricultural crops all over the world (Makovitzki et al. 2007). At this moment, the prevention and control management of plant pathogenic fungi is achieved mainly by the use of synthetic fungicides. However, the massive and sometimes inappropriate use of the synthetic fungicides in agricultural practices resulted in severe negative effects on multiple levels. On the one hand, the plant pathogens have developed resistance to the fungicidal treatments in use (Secor and Rivera, 2012; Rossall, 2012), and on the other hand, the contamination of the environment - soil (Komárek et al. 2010; Wightwick, et al. 2010), water (Wightwick et al. 2011) and air (Brent and Hollomon, 2007) and of the final products due to fungicide treatment was reported. Therefore, new control formulations for plant diseases represent a real need in the nowadays context of sustainable development in agriculture and ecology area. Plants produce multiple secondary metabolites such as tannins, terpenoids, alkaloids, and flavonoids (Butu et al. 2014a; Kennedy and Wightman, 2011) being in the same time important sources of biologically active molecules possessing antibacterial, antifungal (Negi, 2012) and antioxidant properties (Butu et al. 2014b) In recent years, plants extracts obtained by various methods have raised scientific research interest for their antimicrobial potential (van Vuuren, 2008; Rakholiya and Chanda 2012; Ncube et al. 2012; Mamoci et al. 2011). Moreover, an increasing number of studies are developed for investigation of the antimicrobial effects of medicinal plants for plant disease control. (Satish et al. 2007; Sharmin and Shamsi 2013; Rodino et. al 2013; Manasi et al. 2014) R. solani, a soilborne fungus, is one of the most common phytopathogens that attack tomato (Solanum lycopersicum), potato (Solanum tuberosum), cucumber (Cucumis sativus), peas (Pisum sativum) and many other crops, causing disease such as root rot and damping off ( Ohkura et al.,2009; Agrios, 2005) 240