Abstract

ESCOBAR-AVILA, Ilia Mariana  and  TOVAR-SOTO, Alejandro. Population dynamics of the carrot cyst nematode Heterodera carotae under greenhouse conditions. Rev. mex. fitopatol [online]. 2021, vol.39, n.1, pp.185-197.  Epub May 07, 2021. ISSN 2007-8080.  https://doi.org/10.18781/r.mex.fit.2007-1.

The carrot cyst nematode Heterodera carotae is an important pest of Daucus carota crops. For control measures to be effective, knowledge about nematode population dynamics over time is essential. This study evaluated the population dynamics of H. carotae in carrot over a ten-month cultivation period under greenhouse conditions. In June 2017, 90 pots (3 L volume) were placed in the greenhouse: 60 were filled with nematode naturally infested soil (1200 J2/pot) and the remaining 30 were controls (without the nematode). Ten seeds of carrot were sown into each pot. After germination, pots were destructively sampled every 15 and 30 days (n=3). Roots from each pot were weighed and stained. J2s and cysts were extracted from soil. J2 populations in soil and roots behaved similarly. In soil, three J2 peaks were observed after 105, 150 and 195 days with 735, 882 and 967 J2/200 cm3 of soil, respectively. A multiplication factor of 1.6 was calculated and five generations of the nematode were observed. H. carotae caused an average 70.8% yield loss during the experiment. The results can be used in the development of decision-making tools to optimize the implementation of management measures.

Keywords : cyst-forming nematode; Daucus carota; multiplication factor; life cycle; generations; endo-radicular stages.