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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.

Meloidogyne enterolobii (syn. M. mayaguensis) has been reported to cause severe damage in commercial guava orchards and other plants in Central and South American countries. Considering the risk of introduction and dissemination of this pest in the European region, M. enterolobii was placed on the EPPO A2 list in 2010. The use of non-host fruit species is a recommended strategy to manage root-knot nematodes in infested guava orchards. This study screened 89 plant genotypes from 25 fruit plants of economic importance, plus two susceptible controls (guava and tomato) for its host status to M. enterolobii. Three to eight months after inoculation, nematode reproduction factor (RF) was used to characterize host suitability of fruit crops to this nematode. Ten banana genotypes, six Barbados cherries, one fig, two grape rootstocks and six melons were rated as good hosts for this nematode. Sixteen fruit plants behaved either as non-hosts or poor hosts to M. enterolobii, including assai, atemoya, avocado, cashew nut, citrus, coconut, grape, jabuticaba, mango, mulberry, papaya, passion fruit, sapodilla, soursop, starfruit and strawberry. For the future, field experiments in areas infested by this nematode are essential to confirm the greenhouse results. These non-host fruit species can replace in the future eradicated guava trees in fields severely infested by this nematode and become an economic option for growers where M. enterolobii is considered a serious problem.