Meloidogyne incognita parasitizing coffee plants in southern Minas Gerais, Brazil

Abstract

Root-knot nematodes (RKNs), Meloidogyne spp., represent a serious threat to coffee production in Brazil. Although Meloidogyne exigua is widely spread in southern Minas Gerais, a major region of coffee production, no major yield losses have been reported for this nematode. Due to the risk of introducing other more aggressive nematode species into coffee fields, such as M. incognita and M. paranaensis, a survey for Meloidogyne spp. in coffee fields was carried out in this region. Based on esterase phenotypes and SCAR markers, RKNs were detected in 37.7% of samples, of which M. exigua and M. incognita were present in 31.1% and 2.2% of samples, respectively. Mixed populations were observed in 4.4% of samples, i.e. M. exigua + M. incognita + M. paranaensis, or M. exigua + M. incognita. Meloidogyne exigua was the most prevalent species and occurred in majority of counties. Using SCAR markers, M. incognita is reported for the first time in coffee fields located in three counties (Tres Pontas, Coqueiral and Aguanil) in southern Minas Gerais. Nematode containment strategies are recommended for this region.