T. KLEIBER and M. GRAJEK
Poznań University of Life Sciences, Department of Plant Nutrition, 60-198 Poznań, Poland
KLEIBER, T. and M. GRAJEK, 2015. Tomato reaction on excessive manganese nutrition. Bulg. J. Agric. Sci.,21: 118–125
Manganese (Mn) is a heavy metal essential for plant growth. Most of the groundwater to a depth of 100 m used to nutrient solution prepare contain up to 0.5 mg Mn dm-3. However, sometimes water may contain up to 10 mg Mn∙dm-3. About 5% of waters contain from 1 to 4.5 mg Mn∙dm-3. The optimal manganese concentration for tomato cultivation ranges between 0.3 to 0.6 mg∙dm-3 of nutrient solution The aim of the conducted study was to assess the effect of Mn stress (concentration in nutrient solution at 2.4 to 24.0 mg∙dm-3) on plant growth, nutrient uptake and yielding. The model plant was tomato (Lycopersiconesculentum Mill.cv. ‘Alboney F1’). Mn stress did not significantly affect the number leaves, flowers per inflorescence and visible clusters on the plants. Increasing Mn stress had a significant effect on the fresh weight of leaves, stalks, shoots and fruits. The biomass production was reduced by about 17.6%. Mn application resulted in the deterioration of qualitative and quantitative yield of tomato (total yield reduction by about 25.7%). In spite of the significant decrease of biomass production in all the studied combinations there were no other visual symptoms of Mn toxicity to plants. Mn stress significantly affected nutrient uptake, both macro- like micronutrients, especially on increasing content of microelement ion in plants parts. The highest content of Mn in plants was found in leaves, later in stalks and the lowest in case of fruits. It was found almost complete correlation between increasing Mn nutrition and between Mn content in leaves, stalks, fruits and whole plants (R. Pearson ranged from 0.94 to 0.99). Almost complete correlations were also found between Mn content in leaves in relation to fruits, stalks: leaves as well as a very high correlation for Mn concentration in stalks: fruits.