Plant parasitic nematodes associated with chickpea in southern Spain and effect of soil temperature on reproduction of Pratylenchus thornei.

Abstract

Surveys of 63 fields in the chickpea growing area of the Guadalquivir Valley of Andalucía, southern Spain, in 1990 and 1991, indicated that Pratylenchus thornei was the predominant plantparasitic nematode, being recovered from 92% of soil and 84% of root samples, with population densities ranging from 2-48/100 cm3 and 6-70 per g of fresh root. Substantial populations of the ectoparasitic nematodes Amplimerlinius magnistylus, Aorolaimus perscitus, Helicotylenchus tunisiensis, Merlinius brevidens, Mesocriconema curvatum and Paratrophurus loofi were also found. Three populations of P. thornei were tested in a glasshouse at 15, 20 and 25°C at an inoculum density of 2500 nematodes per plant to determine the effect of temperature on nematode reproduction on chickpea cv. UG 27. Reproduction increased with increase of soil temperature. A population from Jerez had a reproduction rate significantly higher than the other two populations at each of the temperatures. Shoot wight of chickpea was not affected by nematode population or soil temperature. At 25°C root weight was significantly lower with a P. thornei population from Cañete.