6 ref. Sum. (En)

This investigation evaluated the effect of two foliar amendments, cellulose (1 and 2 g/L) and glucane (40 and 80 g/L of colloidal glucane 0.28 percent p/v), and five antagonists obtained from the CATIE's collection namely, Serratia sp. (054), Penicillium spp. (067 y 071), Trichoderma sp. (069) and Fusarium sp. (108), on the development of Phytophthora infestans in tomato plants cvs. Hayslip and Pieraline. All the antagonists evaluated showed a clear effect of interfering with disease development under controlled. Penicillium sp. (067) was the best antagonist having presented the least severity when applied with foliar amendments and, in addition, did not allow disease development when applied without foliar amendments irrespective of the concentration used. The best foliar amendment evaluated was cellulose (2 g/L) because lower levels of disease severity and longer incubation periods were observed when combined with the evaluated antagonist, except with Trichoderma sp. (069). Tomato cv. Pieraline was tolerant to P. infestans infection because no disease symptoms were observable. These results provide important information on the biological control of P. infestans and suggest the need to continue working with other antagonist and combinations of foliar amendments.