Characterisation and parasitic habits of a root-lesion nematode from chrysanthemum in Iran and its relationship to Pratylenchus pseudocoffeae

Abstract

AbstractA population of the amphimictic root-lesion nematode Pratylenchus pseudocoffeae is reported infecting chrysanthemum in glasshouses and open fields in Mahallat Town, Markazi province, central Iran. This population shares similar morphological features with P. pseudocoffeae from Japan and also has the same D3 sequences as a population from Florida (no molecular data are available for the type Japanese population). The Iranian population of P. pseudocoffeae is characterised by a labial region with two (60%) or three annuli (40%), stylet ca 16 μm long, presence of males, vulva at 80% of body, oval spermatheca and subhemispherical tail with smooth terminus. Morphologically, P. pseudocoffeae from Iran resembles P. coffeae, from which it differs in a divided face vs smooth and flat in P. coffeae. However, the morphological and biological characters of P. pseudocoffeae are more closely related to those of P. gutierrezi and the related undescribed species K1 and K2 from coffee in Costa Rica and Guatemala, respectively, from which it differs by the shorter stylet and shape of tail tip. In contrast, the comparison of molecular characteristics, including ITS-RFLP patterns and sequences of the D3 region between P. pseudocoffeae from Iran and other related species, indicates a close relationship between P. pseudocoffeae and P. hexincisus and P. agilis, in spite of the fact that the latter two species are not amphimictic and lack males and functional spermatheca. In Iran, P. pseudocoffeae causes root lesions, distinct necrosis and large cavities within the cortical parenchyma, resulting in stunting of chrysanthemum stands. The detection of P. pseudocoffeae in Iran is a new country record and also represents the second detection of this species outside Japan.