Response of 35 Cacao Collections of ICCRI against P. palmivora Butl. Infection Based on Detached Pod Assay

Abstract

These research activities were conducted to evaluate the respone of cacao collection against infection of black pod disease due to Phytophthora palmivora. The objectives of this experiment were (i) to evaluate the respone of 35 cacao clones against infection of P. palmivora using detached pod assay, (ii) to determine the most resistance cacao clones, and (iii) the most susceptible cacao clones among evaluated cacao germplasm collection against infection of P. palmivora. In the experiment, pods of 35 cacao clones (at 4-5 months after anthesis) were harvested and inoculated with mycelia of P. palmivora in the laboratory. Observations were conducted on length and width of necroses symptoms because of P. palmivora infection on the surface of the tested pods. Results of the experiment showed cacao clone ICRI 1, PA 300, ICRI 3, UIT 1, NIC 4, DR 38, ICS 13, TSH 858, SCA 6, and ICS 60 were the ten most resistance cacao clones against infection of P. palmivora. On the other hand, cacao clone RCC 73(3), KKM 22, NIC 7, DRC 16, RCC71, BL 300, BL 301, KEE 2, TSH 908, and DRC 15 were the ten most susceptible cacao clones against infection of P. palmivora