Investigating the pathogenicity and loss of root knot nematode (Meloidogyne javanica) on several stocks and scion composition of almond

Root knot nematodes (Meloidogyne spp.) are one of the important limiting factors in almond production. Use of resistant rootstocks to plant pathogens is the most effective methods for control of soil-borne pathogens, especially nematodes. In this study, the reaction of several stock and scion composition (Sefeid and Mamaei as scion and GF677, GN15, shorabi 1 peach × almond hybrid and shorabi 2 peach × almond hybrids as rootstock) to root knot nematode (M. javanica) was studied as a randomized complete block design with four replications in greenhouse. The nematodes were added to pots one week after grafting cultivars. Scion growth indices and nematode pathogenicity parameters were evaluated three months after inoculation. Analysis of variance and mean comparison of results showed the susceptibility of all rootstocks, except GN15. Among the susceptible rootstocks to nematode, the highest scion growth was observed on Shorabi 2 peach × almond hybrid. Compatibility of Mamaei (as scion) and Shorabi 1 and Shorabi 2 peach × almond hybrids (as rootstock) increased tolerance to nematode. Collectively, the GN15 and peach × almond hybrids rootstocks were more resistant to root knot nematode than other examined rootstocks. The sensitivity or tolerance of rootstocks to nematodes was affected by the type of grafted variety on different rootstocks.