Some effects of tentoxin on mature and developing chloroplasts.

Tentoxin affected chloroplasts of all stages of development; it caused chlorosis of expanded and developing bean and lettuce leaves when introduced through the stem or roots and inhibited greening of etiolated lettuce seedlings. Cotyledons from 6-day-old lettuce seedlings grown in 10 mug/ml tentoxin had 50-68% of the monogalactosyldiglyceride and digalactosyldiglyceride content of healthy tissue whereas the sulfolipid, phosphatidyl-glycerol, -ethanolamine, -choline and -inositol levels were unchanged. Toxin-treated tissue also showed selective increases in C-16 and C-18 saturated fatty acids.