BIO-ECOLOGICAL CRARACTERISTICS OF TRE CEREAL CYST NEMATODE HETERODERA A VENAE IN SPAIN

Abstract

The life cycles of Heterodera avenae populations from three cereal growing areas in Spain with mediterranean continental climate, showed similar biological characteristics to those from other mediterranean countries. Juvenile emergence starts in the autumn. Second stage juveniles undergo a diapause of four months, followed by a period, probably of quiescence in which hatching is possible if moisture is suitable. An increase of emergence was observed at the beginning of spring, and was more evident for populations from areas with the most extreme climatic characteristics. This can be considered as an adaptation of the nematode to climatic conditions that allow it to develop in an area in which spring sowing is a frequent cultured practice.