Resistance to nematode 'Meloidogyne paranaensis' in arabica coffee genotypes introgressed with 'Coffea liberica'

• Published in: Australian Journal of Crop Science Vol. 14; no. 8; pp. 1236 - 1241
• Main Authors: Sera, Gustavo H., Carvalho, Filipe G., Fonseca, Inês C. de B., Shigueoka, Luciana H., Silva, Santino A. da, Silva, Angelita G. da, Ito, Dhalton S.
• Format: Journal Article
• Language: English
• Published: 01.08.2020
• Subjects: Breeding; Coffee; Evaluation; Nematodes
• ISSN: 1835-2693; 1835-2707
• DOI: 10.21475/ajcs.20.14.08.p2240

The aim of this study was to prove that Arabica coffee introgressed with C. liberica, have resistance to Meloidogyne paranaensis (Mp). Open pollinated fruits were harvested from mother plants of 29 Arabica coffee genotypes from the IAPAR germplasm bank. Seeds were collected from the fruits and were sown to obtain seedlings to test the resistance to Mp. The experiment was set up in a completely randomized design with 29 coffee genotypes, 8 replications, and one plant per plot. Cultivars Catuai Vermelho IAC 99 and IPR 100 were used as susceptible and resistant checks, respectively. Seedlings with three to four pairs of leaves were inoculated with 1,400 eggs and juveniles J2 of Mp (IP). At 120 days after inoculation, seedlings were evaluated by counting the nematodes per gram of roots, and the final nematodes population was obtained (FP). The reproduction factor (RF) was calculated using the formula: RF = FP/IP. The reproduction factor reduction was used to classify the resistance levels of genotypes, which were classified as highly resistant (HR), resistant (R), moderately resistant (MR), moderately susceptible (MS), susceptible (S) an highly susceptible (HS). All genotypes differed from Catuai in resistance factor (RF), five of which did not differ from IPR 100 for RF, and only the line IAPAR 15242 had RF < 1.0. Out of 28 Arabica genotypes introgressed with C. liberica, five HR, 11 R, 11 MR and one MS were identified. However, only IAPAR 15242 and IPR 100 were classified as HR and presented 100% of HR plants, but only the first showed an RF < 1.0. Results revealed that these Arabica coffee genotypes with introgression of C. liberica genes have great potential to be used in breeding programs and they are a new alternative as a source of resistance.