BILJANA PLAVSIC, KRSTO KRIVOKAPIC, ZlVOJIN ERIC and DEVLETA BUTUROVIC

In this study we investigated the influence of kinetin (6-furfurylaminopurine) on stolbur infected tomato plants. By using electron microscopy we analysed the starch accumula­ tion and the thylakoid membranes in the chloroplast and we quantified the photosynthetic pigments by spectrophoto­ metry. Consideration was also given to the growth and ge­ neral appearance of the plants. We proved that in stolbur infected plants kinetin provoked the degeneration of MLO (mycoplasma like organism), the syntesis of photosynthetic pigments, regenerated the thylakoid membranes, and increas­ ed the hydrolysis of starch accumulated in the chloroplast. After kinetin treatment, diseased sterile plants produced normal flowers, fruit, and viable seeds which gave healthy progeny.