The effect of sodium humane on the growth of tomatoes and the accumulation of phosphorus and iron in mediums of different pH

The effect of sodium humate on changes in the phosphorus and iron content in shoots of tomatoes cultivated in mediums with a raised or lowered pH and phosphorus dose (compared with controls) were analysed. At low pH, sodium humate increased the accumulation of phosphorus and lessened the excessive accumulation of iron in plants cultivated under conditions of phosphours deficit. At a slightly alkaline pH, sodium humate prevented excessive, accumulation of phosphorus and raised low iron contents. A favorable effect of humate on dry mass production was clearly seen at pH 6.4