Abstract
Phytoalexins, compounds produced by plants in response to pathogens, and biologically active metabolites produced by endophyte are beneficial to plant growth. There are many trials to utilize these biologically active substances for plant disease control. On the other hand, some of these substances are toxic to mammals. We experienced ryegrass staggers of cattle caused by endophyte infected ryegrass straw. In this review, toxicities of phytoalexins and endophyte related substances to animals are overviewed. Furthermore, toxic substances found in false smut balls in rice plant are cited.
