Evaluation of Lolium rigidum biotypes resistance to chlorsulfuron: useful parameters
N de la Carrera, M Villarroya, M C Chueca and J M Garcia-Baudin, INIA, Madrid, Spain

Dose response curves of resistant and susceptible Bidens pilosa to ALS inhibitor herbicides
P J Christoffoleti, Universidade de São Paulo, Brazil
L L Foloni, Universidade de Campinas, São Paulo, Brazil

The level of polyamines as an indicator of resistance or susceptibility of Chenopodium album to atrazine
J Giebel, S Stachecki and T Praczyk, Institute of Plant Protection, Poznañ, Poland

Mechanism of isoproturon resistance: the metabolism of isoproturon in susceptible and resistant biotypes of Phalaris minor
G Kulshrestha, S B Singh and N T Yaduraju, IARI, New Delhi, India

An investigation of glutathione S-transferase activity in Alopecurus myosuroides (blackgrass) in the field
L J Milner, J P H Reade and A H Cobb, Harper Adams University College, Newport, UK

The occurrence of herbicide-resistant grass-weeds in the United Kingdom and a new system for designating resistance in screening assays
S R Moss, IACR-Rothamsted, Harpenden, UK
J H Clarke and A M Blair, ADAS Boxworth, Cambridge,UK
T N Culley, Zeneca Crop Protection, Haslemere, Surrey, UK
M A Read, AgrEvo UK, King’s Lynn, UK
P J Ryan, Novartis Crop Protection UK Ltd, Cambridge, UK
M Turner, Oxford Plant Sciences Ltd, Bicester, UK

Rapid tests for herbicide resistance in blackgrass based on elevated glutathione S-transferase activity and abundance
J P H Reade, J L Belfield and A H Cobb, Harper Adams University College, Newport, UK

Activity of tepraloxydim (BAS 620H), a new cyclohexanedione herbicide, on herbicide-resistant blackgrass (Alopecurus myosuroides)
R E Ruske, University of Bath, UK
S R Moss, IACR-Rothamsted, Harpenden, UK

Genetic variation and relationships of herbicide-resistant and -susceptible biotypes of Lindernia micrantha
H Shibaike and K Itoh, National Institute of Agro-Environmental Sciences, Tsukuba, Japan
A Uchino, Tohoku National Agricultural Experimental Station, Akita, Japan