Effect of cytokinins on <Emphasis Type="BoldItalic">in vitro</Emphasis> development of autotrophism and acclimatization of <Emphasis Type="Italic">Annona glabra</Emphasis> L.

The role of cytokinins in the differentiation of the photosynthetic apparatus in micropropagated plants and their effect on the plant’s ability to transition from a heterotrophic to an autotrophic condition during acclimatization was investigated. Annona glabra L. shoots were cultured on woody plant medium supplemented with sucrose and different cytokinins to evaluate leaf tissue for chloroplast development, chloroplast numbers, photosynthetic pigmentation, total photosynthetic potential, and soluble sugar content. Plants were transferred to the rooting medium in the presence or absence of sucrose and then acclimatized. Kinetin and benzyladenine (BAP) stimulated chloroplast differentiation. Inclusion of zeatin in the medium induced the formation of greater numbers of chloroplasts in the leaves, while plants cultivated in the presence of only kinetin and BAP demonstrated greater chlorophyll a and carotenoid content. The use of kinetin and BAP during in vitro culture promoted accumulation of dry matter during the acclimatization phase, especially in plants rooted under autotrophic conditions (without sucrose). Kinetin and BAP promoted development of more leaf area and greater plant survival rates in plant acclimatization on both autotrophic and heterotrophic media. The inhibitory effects of thidiazuron on the differentiation of chloroplasts, accumulation of chlorophyll a, and photosynthetic potential were examined.