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Experiments were conducted to examine the symptom and degree of phytotozicity caused by several dithane fungicides (zinc complex manganese ethylene-bis-dithiocarbamate) sprayed on several vegetable crops and cultivars and at different growth stages. Even though the dithane fungicides had the same chemical constituents, Tanzeo M-45 and Othane M-45 showed moderate to severe phytotoxicity in all tested vegetables whereas Dithane M-45 showed little or no phytotoxicity in most vegetables. In general, the higher the concentrations, the severe the symptom. Phytotoxicity was most severe in tomato seedlings followed by cucumber, watermelon, pepper, and muskmelon, in that order. The symptoms were mostly confined to stem base (and roots) near the ground level. The peripheral cells or tissues of this portion showed the .most severe injury and shrunk and, in severe cases, the seedlings collapsed and survived in poor conditions or began to wilt. No differences in phytotoxicity were observed in 5 pepper cultivars tested. The injury was severe in younger seedlings, especially in tomatoes.
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