Host suitability of twelve common weeds to Pratylenchus penetrans and Meloidogyne hapla in potato fields of Bulgaria

H. Samaliev, Sht. Kalinova

Abstract: Twelve weeds commonly found in commercial potato fields in Bulgaria were evaluated in a pot trial for their host suitability to Pratylenchus penetrans and Meloidogyne hapla. Apepa spica-venti (L) P.B., Elytrigia repens (L.) Nevski, Cirsium arvense (L.) Scop., Chenopodium album L. and Solanum nigrum L. were hosts of P. penetrans with multiplication rates of 1.5, 1.6, 1.7, 1.9 and 2.0, respectively. The multiplication factor of P. penetrans on Echinochloa crus-galli L. was similar to the one recorded on Nicotiana tabacum L., the susceptible control. Sorghum halepense (L.) Pers. was non-hosts as no specimen of the target nematode was found in the roots. Amaranthus retroflexus L. is considered a poor host with low population densities in the root. In fallow pots after 14 weeks, only 7.47% of the population of P. penetrans was still alive. Chenopodium album L. and Cynodon dactilon (L.) Pers. were not hosts for M. hapla as the end of the experiment there were no significant differences between the population in the fallow pots and in these weeds and no egg masses and eggs were observed on these weeds. Cirsium arvense (L.) Scop., Echinochloa crus-galli L., Lamium amplexicaule L. and Portulaca oleracea L. with few egg mass producing per root plant, but maintaining significantly higher population densities in the soil than were recorded in the fallow pots and is considered a poor host. Convolvulus arvensis L. and Solanum nigrum L. were hosts of the M. hapla with reproduction factors of 1.81 and 5.50, respectively. Fourteen weeks after inoculation of fallow pots, only 2.93% of the population of M. hapla was still alive.

Keywords: Host range; Meloidogyne hapla; natural decline; potato fields; Pratylenchus penetrans; reproduction factor; weeds

Date published: 2019-03-25