Resistance to Meloidogyne mayaguensis in Psidium spp. accessions and their grafting compatibility with P. guajava cv. paluma.
Meloidogyne mayaguensis has been reported in some states of Brazil causing severe damage on commercial guava (Psidium guajava). Accessions of Psidium spp. were selected from a collection maintained in Embrapa Clima Temperado (Pelotas, Rio Grande do Sul State). Plants of different accessions were grown from seeds in plastic bags and, when they reached 15-20 cm in height, were inoculated with 10 000 eggs per plant of M. mayaguensis. Eight months after inoculation, the different accessions were evaluated for resistance to M. mayaguensis. Three accessions of P. guajava were highly susceptible (RF=59.2) to this nematode. Psidium friedrichsthalianum was considered to be moderate (RF=1.9). Three accessions of P. cattleianum were immune to M. mayaguensis (RF=0). When used as rootstocks, P. cattleianum and P. friedrichsthalianum were compatible with P. guajava cv. Paluma. The use of resistant rootstocks provides a promising control method for M. mayaguensis commercial guava crop.