The Availability of Iron in Nutrient Solutions for Wheat

Abstract

The efficiency of the usual trace of iron when employed in culture solutions may be expected to vary with the nature of the compound in which it is supplied, with the composition and reaction of the solution in which it is employed, and with the species of plant. Gile and Carrero have shown that the reaction of the nutrient solution (whether acid, neutral, or alkaline) (6), as well as soil conditions (7), have a marked influence upon the availability of iron to the rice plant. Corsan and Bakke (4) count ferrous iron less efficient than ferric iron, when used in the forms of phosphates. Jones and Shive (9) have pointed out that, in the nutrient solution which they employed, iron in the form of ferrous sulphate was very readily available to the wheat plant, but was evidently somewhat toxic in the highest concentrations used. Ferric phosphate, on the contrary, was very slowly and difficultly available to these plants, even when supplied in relatively large quantities. In later work (10) they found that ferrous sulphate was superior to ferric phosphate as a source of iron for plants grown in a nutrient solution containing calcium nitrate. When ammonium sulphate was employed as the source of nitrogen, however, the solution increased in acidity and ferric phosphate supported growth of the plants better than did ferrous sulphate. Hoagland (8) has suggested that the presence of sufficient dissolved iron in the culture solution will depend upon the form and quantity of the iron salt used, and considers iron citrate and tartrate the most effective forms. Duggar (5) has recommended a special form of "soluble" iron prepared from ferric citrate and sodium phosphate. EXPERIMENTATION SolubilityIn the present investigation an attempt was made to determine which of the following salts of iron, namely: ferric citrate, FeP0 4, Fe2(S04)a, and FeS04' would remain in solution in the greatest amounts at the two hydrogen-ion concentrations of pH 4.2 and pH 6.0, using the Livingston-Tottingham nutrient solution; and also to determine which of these forms of iron would be most available to the wheat plant when supplied in varying amounts, at the latter pH value of the nutrient solution.

The rôle of aluminium in soil infertility and toxicity

“…That certain complex co-ordinated metal anioris may readily penetrate and suffer translocation is indicated by recent researches on the assimilation of iron by plants from nutrient solutions (11,21,24,41,42,45,50,52), and on the transportation and accumulation of aluminium and iron in certain plants growing under field conditions (35,52). Among the mobile complex metallic anions may be mentioned alumino-oxalate ion A1(C 2 O 4 ) 3 , ferro-citrate ion, ferro-tartrate ion and ferro-polyhydroxyphenolic ions.…”

Plant growth with nutrient solutions: I. A brief review of existing work

“…Cereals have been used for much of the work with nutrient solutions, in particular wheat, cf. Bakke & Erdman (1923), Brenchley (1916), Brown (1928), Gericke (1921Gericke ( ,1922, Jacobson (1925), Jones & Shive (1922), Jones & Pember (1925), Livingstone & Tottingham (1918), McCall (1916a, McCall & Haag (1921), McCall & Richards (1918), Meier & Halstead (1921), Schreiner & Skinner (1910), Sewell (1924), Shive (1915 a, b), Tottingham (1914), Tottingham & Rankin (1923), Trelease (1917), Trelease & Trelease (1925, 1926, Trelease & Free (1917), etc. Other cereals used are barley (Stiles, 1915;Brenchley, 1916;Hoagland, 1919Hoagland, , 1920Pember, 1917;Hoagland & Martin, 1923;Wolkoff, 19186;Jones & Pember, 1925), oats (Jones & Pember, 1925), rye (Stiles, 1915), corn (Tarr & Noble, 1922;Duggar, 1920 a, 6), rice (Jacobson, 1925), and buckwheat (Shive, 19186;Shive & Martin, 1918 a, 6;Free, 1917).…”

Observations on the ‘Staling’ of White's Medium by Excised Tomato Roots. II Iron Availability

“…Experiments No. [27][28][29][30] were Ihen undertaken to test the effect oi the pnrified monosaccharides on the growth-promoting activity of White's medium whose pH had been raised by addition of alkali. White's medium, wben containing added monosaccharides, shows on autochiving a variable acid drift suggesting the formation of sugar acids from the monosaccharides.…”