The effect of manganese on the growth of tomato cells in suspension culture

Abstract

The effects of Mn2+ concentration in the culture medium on the biomass production, nutrient content, cell division and viability were studied using tomato cells in suspension culture. The biomass and the dry weight were highest at Mn levels of 0.002 and 0.1 mM when compared with cells grown with 0 or 0.2 mM Mn in the medium. Cells cultured on 0.2 mM Mn turned black by day 6. Cells grown without added Mn (0 mM) turned brown by day 8. The total number of cells as well as the number of viable cells were lowest with Mn levels of 0 and 0.2 mM. Manganese levels of 0.2 and 0 mM in the medium led to toxicity and deficiency respectively. By day 8 all the macro-and micro-elements of cells grown either with 0.2 and 0 mM Mn were low. This was probably due to the change in the cell membrane permeability which had led to the leaching of cell contents under the latter two Mn concentrations. There were no significant differences in the nutrient content of cells over a Mn range of 0.1 and 0.002 mM in the medium. Therefore in spite of a concentration difference of 50 fold, tomato cells showed no deleterious effects to medium Mn within the latter concentration range.