Effect of Zinc application on vegetative growth and toxic accumulation of Sodium chloride on tomato (Lycopersicon esculentum Mill.) under salinity conditions

Abstract

An experiment was conducted in one of the plastic houses belong to the Kufa Technical Institute during the growing season of 20092010 , to study the effect of different concentrations of Zinc on the toxicity of Sodium chloride for tomato plants grown in soil that suffer from Zinc deficiency. The experiment included three conc. of Zn i.e.(Zero, 3, 12) mgZnKg. Soil and three conc. of NaCl, i.e.(Zero%,0.5% and 1.5%) ,which added to irrigation water . After 60 days from growth, plants had harvested. Dry matter, Zn, Na, K, P and K/Na ratio were determined. Results showed that there was highly decrease in the amount of Zn in the soil which reflected its effect in the decrease of growth, particularly in highly salty condition (1.5%). Increasing in NaCl resulted in a decrease in the amount of vegetative parts dry matter, this reduction was higher with soil that treated with 3 mg ZnKg soil compared with soil that treated with 12 mg Zn Kg soil. Addition of Zn from 3-12 mg ZnKg soil caused an increase in K conc. from 37.8 to 40.9 ; 25.6 to 30.6 ; 21.0 to 22.9 mgg dry matter, respectively, and a decrease in the Na conc. from 3.6 to 0.7; 8.7 to 5.4 and 28.7 to 21.9 according to the conc. of NaCl that used (i.e. Zero, 0.5 and 1.5%), respectively . Consequently , K/Na ratio of plants were highest in the highest Zn application conditions .Result of experiment also revealed that importance of Zn to improve plant tolerance to soil salty conditions and the use of suitable amount of Zn causes an absorption increase of Na by roots in salty conditions.It could be concluded that the use of suitable amount of Zn of importance for plants survival at convenient degree of growth at salty conditions.