On-line version ISSN 1678-992X
BORGATTO, Fábio; DIAS, Carlos Tadeu dos Santos; AMARAL, Antônio Francisco Campos and MELO, Murilo. Calcium, potassium and magnesium treatment of Chrysanthemum morifolium cv. "Bi Time" and callogenesis in vitro. Sci. agric. (Piracicaba, Braz.) [online]. 2002, vol.59, n.4, pp. 689-693. ISSN 1678-992X. http://dx.doi.org/10.1590/S0103-90162002000400011.
The chemical composition and vegetative vigor of the donor plant are essential for the satisfactory performance of explants in vitro. In order to test the effect of potassium, calcium and magnesium nutritional status of Chrysanthemum morifolium plants on callogenesis in vitro, pot plants growing in sand were irrigated with nutrient solution containing different levels of potassium (0; 58.5; 117 and 234 mg L-1), calcium (0; 50; 100 e 200 mg L-1) and magnesium (0;12; 48 e 96 mg L-1). After 30 and 45 days, explants (shoot segments and leaf discs) were collected, desinfected and inoculated on MS solid medium supplemented with 0.1 mg L-1 of kinetin and 5.0 mg L-1 of nafthalene acetic acid for callogenesis induction. Callogenesis evaluated as callus fresh weight was affected by nutrients treatment. Callus growth on leaf explants was inversely proporcional to potassium concentration and directly proportional to magnesium concentration in shoot explants. The calcium effect on callogensis of leaf explants was dependent on treatment duration. For 30 days treatment callogenseis was inversely related to calcium concentration and after 45 days was directly related to calcium concentration.
Keywords : matrix plant; mineral nutrition; tissue culture.