Soil pH and Manganese Effects on Manganese Nutrition of Peanut¹

Abstract

Manganese deficiency of peanut (Arachis hypogaea L.) is a common problem on some soils of the Coastal Plain region of the southern USA. Information is limited, however, on the concentration of Mn required in the peanut plant. 'Fiorunner' peanut was grown on a Pelham sand (loamy, siliceous, thermic, Arenic Paleaquult) to determine soil pH and Mn effect11 on Mn nutrition of peanut. Soilapplied Mn treatments of 0, 10, 20, and 40 kg ha-• were compared at pH levels near 5.2, 6.0, and 6.8. Manganese deficiency occurred only on plots with pH levels near 6.8 where yields were increased by applying up to 40 kg Mn ha-•. Critical Mn levels were 13,15,15,15,13, and 12 mg kg-• in leaves collected at 7, 9, 11, 13, 15, and 17 weeks after planting, respectively. Pod yields averaged 3.41, 5.40, and 5.73, and 6.37 Mg ha-• at pH level near 6.8 for 0, 10, 20, and 40 kg Mn ha-• tt.eatments, respectively. Maintaining a soil pH near 6.0 provided a desirable medium for peanut production without the need for Mn fertilizer.------------------

Soil zinc and pH effects on leaf zinc and the interaction of leaf calcium and zinc on zinc toxicity of peanuts

“…Leaf Ca was higher for the samples taken in September than those in August. These data are in agreement with a previous report (18) Soil Zn increased with increased Zn rates and the range in concentration increased over time (Tables 2 and 3) apparently because the amount of Zn for the two applied rates were doubled in 1983 and 1984 over that applied in 1982. The amounts for the two plus treatments were increased in 1983 and 1984 in an attempt to induce Zn toxicity, but this was not accomplished since none of the peanut plants had Zn toxicity symptoms.…”

“…Soil pH had no effect on Mehlich No. 1 extractable Zn but increased soil pH levels resulted in drastic reduction of Zn in peanut leaves and shoots (18). Concentrations of Zn in peanut leaves on 3 September, 15 weeks after planting, were 250, 69, and 14 mg/kg for soil pH levels of 5.2, 6.0, and 6.8, respectively, when Mehlich No.…”

Zinc Uptake from Soils

“…Diffusion coefficients for zinc in calcareous soils may therefore be about 50 times lower than in acid soils, and liming of acid soils leads to a decrease in diffusion coefficient of zinc similar to values found in calcareous soils (Moraghan and Mascagni, 1991). Liming acid soils sharply decreases zinc contents in plants ( Grove and Sumner, 1985;Parker and Walker, 1986) with the risk of inducing zinc deficiency in plants grown in highly weathered tropical soils low in zinc (Duguma et aI., 1988). Despite the sharp decrease in zinc content in plants, the DTPA extractable zinc in soils is often not, or only slightly decreased (Lins and Cox, 1988), suggesting that the "rate" and "intensity" of zinc ( Fig.…”

Control of nutrient solutions for studies at high pH

“…Iron deficiency (lime-induced chlorosis) is the most common nutritional disorder of plants growing on alkaline soils and is caused both by low Fe availability and by elevated concentrations of HCO − 3 (Marschner, 1995;Russell and Wild, 1988). The availability of other nutrients such as Ca, Zn, P and Mn, is also low in alkaline conditions due mainly to adsorption and precipitation processes (Parker and Walker, 1986;Srivastava and * FAX No: +61-7-3365-3452. E-mail: p.kopittke@uq.edu.au Sethi, 1981).…”