After inoculation of 14 days old chickpea ( Cicer arietinum L.) plants with pycnidiospores of the fungal pathogen Ascochyta rabiei (Pass.) Labr. a strong accumulation of intracellular and extracellular β-1,3-glucanase activity was observed during a 6 days infection period. Extracellular β-1,3-glucanase activity starts to increase 2 days post inoculation, 1 day earlier than the intracellular activity. In the apoplast at least 10 proteins accumulate after inoculation. One of these proteins was identified as a β-1,3-glucanase, not detectable in leaf homogenates. This hitherto unknown enzyme (PR-2b) was purified and characterised. PR-2b has an apparent molecular mass of 34 kDa and an isoelectric point of 5.9. The pH optimum was 5.2. No inhibitory effect towards the inducing pathogen A. rabiei was detected in in vitro studies. In time course studies no quantitative or qualitative difference of extracellular β-1,3-glucanase accumulation was observed between a resistant (ILC3279) and a susceptible chickpea cultivar (ILC1929).