Effect of Zinc Humate on Growth of Soybean and Wheat in Zinc‐Deficient Calcareous Soil

Abstract

Humic acids have many benefits for plant growth and development, and these effects may be maximized if these materials are combined with micronutrient applications. In the present study, pot experiments were conducted to evaluate the effects of zinc (Zn) humate and ZnSO 4 on growth of wheat and soybean in a severely Zn-deficient calcareous soil (DTPA-Zn: 0.10 mg kg 21 soil). Plants were grown for 24 (wheat) and 28 days (soybean) with 0 or 5 mg kg 21 of Zn as either ZnSO 4 or Zn humate. Zinc humate used in the experiments was obtained from Humintech GmbH, Germany, and contained 5% of Zn. When Zn was not supplied, plants rapidly developed visible symptoms of Zn deficiency (e.g., chlorosis and brown patches on young leaves in soybean and necrotic patches on middle-aged leaves in wheat). Adding Zn humate eliminated Zn-deficiency symptoms and enhanced dry matter production by 50% in soybean and 120% in wheat. Zinchumate and ZnSO 4 were similarly effective in increasing dry matter production in wheat; but Zn humate increased soybean dry matter more than ZnSO 4 . When Zn was not supplied, Zn concentrations were 6 mg kg 21 for wheat and 8 mg kg 21 for 2769 Downloaded by [Akdeniz Universitesi] at 12:45 21 December 2014 soybean. Application of Zn humate and ZnSO 4 increased shoot Zn concentration of plants to 36 and 34 mg kg 21 in wheat and to 13 and 18 mg kg 21 in soybean, respectively.The results indicate that soybean and wheat plants can efficiently utilize Zn chelated to humic acid in calcareous soils, and this utilization is comparable to the utilization of Zn from ZnSO 4 . Under Zn-deficient soil conditions, plant growth and yield can be maximized by the combined positive effects of Zn and humic acids.

Effect of Humic Acid on Growth and Productivity of Tomato Plants Under Heat Stress

“…The reasons behind this increment are connected with each other. Also, several studies have shown that HA has the ability to decrease the harmful effect of stressors on plants (Ozkutlu et al 2006;Rajaei 2010;Unlu et al 2011;Moraditochaee 2012) and in soils (Baldotto et al 2010). In our experiments, HA similarly positively influenced the growth and yield parameters of two tomato hybrid cultivars.…”

Effects of Zn and P addition on the microbial biomass in a Zn deficient calcareous soil amended with glucose

“…The soil is a Haplic Calcisol according to the WRB-FAO classification system (FAO 2006). Soils similarly low in soil organic matter as the present soil have been used for pot experiments for investigating the effects of Zn deficiency on plants (Cakmak et al 2001;Özkutlu et al 2006). The field moist soil was sieved (<2 mm), adjusted to 50% water holding capacity, and pre-incubated for 1 week.…”

“…Consequently, soil organic matter plays a critical role in solubility and transport of Zn to plant roots (Obrador et al 2003;Cakmak 2008). Soils low in organic matter such as subsoils demonstrate most clearly the negative effects of Zn deficiency on plant growth in pot experiments Özkutlu et al 2006).…”

Zinc application and green manuring enhances growth and yield in basmati rice (Oryza sativa L.)

“…The relatively higher maintenance of available Zn in soil due to applied EDTA-chelated Zn (12 % Zn) may be attributed to the very little or no interaction between soil components preventing various harmful reactions occurring in soil as compared to soil treated with other Zn sources, which enhances greater fixation, adsorption etc., resulting from the greater interaction between soil components. Increase in yield attributes and grain yield of basmati rice with Zn application might be due to higher Zn uptake with Zn fertilization, resulting in higher biomass production (Shivay et al 2008;) and photosynthates translocation to reproductive parts (Ozkutlu et al 2006;Alloway 2008). The increase in yield attributes and grain yield of basmati rice with application of EDTA-chelated Zn (12 % Zn) might be due to the relatively greater amount of Zn uptake compared with other Zn sources.…”