Effective mechanical weed control in processing tomato: Seven years of results

A. Cirujeda1*, J. Aibar2, M.M. Moreno3 and C. Zaragoza1

1Unidad de Sanidad Vegetal, Centro de Investigación y Tecnología Agroalimentaria (CITA), Avda. Montañana

930, 50059 Zaragoza, Spain

2Universidad de Zaragoza, Escuela Politécnica Superior, Ctra. de Cuarte s/n, 22071 Huesca, Spain

3Escuela de Ingenieros Agrónomos, Universidad de Castilla-La Mancha, Ronda de Calatrava 7, 13071 Ciudad

Real, Spain

*Corresponding author: acirujeda@aragon.es

Abstract

Open-air crops are important in Spanish horticulture. The limited number of herbicide active ingredients in minor crops,

the waste problem of polyethylene (PE) plastic mulch and the high prices of biodegradable plastics leave hand-weeding

and mechanical weed control as the most viable weed control methods. Different tools have been tested in northern

European countries but their performance remains unknown in the edaphoclimatic situation of southern Europe. The

objective of this work was to test novel physical weed control methods on processing tomato in northeastern Spain

compared with other effective control methods, i.e., plastic and paper mulches. A first sequence of field trials was

established from 2005 to 2008 at Zaragoza (Spain) to select the best physical control methods out of flamer, torsion

weeder, finger weeder, flex-tine harrow and brush hoe used alone or in combination. The best method was the brush hoe

which was then compared from 2009 to 2011 with PE mulch, biodegradable plastic mulch and paper mulch. Flamer, flextine

harrow, torsion weeder and finger weeder performed quite irregularly due to crusty soil conditions and needed

additional tools or repeated treatments to increase weed control efficacy. The brush hoe performed best in this soil

situation working at about 5 cmdepth. Weed biomass reduction was higher than 80% in 6 out of 7 years and similar yield

was obtained in the brushed plots compared to the yield obtained with PE, biodegradable plastic and paper mulch. The

brush hoe is thus a suitable option for weed control in processing tomato while the other tools were too weak to control

aggressive summer weeds in the tested conditions.

Key words: brush hoe, finger weeder, torsion weeder, flex-tine harrow, flamer, polyethylene mulch, Cyperus rotundus