Igor Palčić

Synthetic Zeolite A as Zinc and Manganese Fertilizer in Calcareous Soil

ABSTRACT The Leccino olive cultivar was grown in pots contained calcareous rendzina soil amended with NPK fertilizer (control treatment) or with further addition of Zeolite A (ZA) containing either zinc (Zn2+) or manganese (Mn2+) (Zn-ZA and Mn-ZA). After one year, vegetative growth and root morphological parameters were measured and elemental analysis was performed on the root, stem, and leaves. Compared to other treatments, the Zn-ZA fertilizer enhanced Zn concentration and total quantity in the root, stem, and leaves, as well as the root diameter. The root volume was greater using Zn-ZA treatment than control treatment. The total quantity of Mn in root and the root length were enhanced when using Mn-ZA compared to control or Zn-ZA treatment. According to the results of this study, it appears that zeolites containing Zn provide favorable conditions for Zn uptake in calcareous soils, while both Zn and Mn zeolites have a positive impact on olive root morphology.

Manganese soil and foliar fertilization of olive plantlets: the effect on leaf mineral and phenolic content and root mycorrhizal colonization: Manganese soil and foliar fertilization of olive plantlets

BACKGROUND The present study aimed to examine the effect of foliar (Mn_fol) and soil Zeolite-Mn (Mn_ZA) application on leaf mineral, total phenolic and oleuropein content, and mycorrhizae colonization of self-rooted cv. Leccino plantlets grown on calcareous soil. RESULTS The dissolution of zeolite was 97% when citric acid was applied at 0.05 mM dm-3 , suggesting that organic acids excreted by roots can dissolve modified zeolite (Mn_ZA), making Mn available for plant uptake. The leaf Mn concentration was the highest for Mn_fol treatment at 90 days after transplanting (DAT) (172 mg kg-1 ) and 150 DAT (70 mg kg-1 ) compared to other treatments. Mn_ZA soil application increased leaf Mn concentration at 150 DAT compared to control and NPK treatments. The oleuropein leaf content was highest for Mn_fol compared to other treatments at 90 DAT and lowest at 150 DAT. Arbuscular mycorrhizal colonization was higher for Mn_fol treatment at 150 DAT compared to all other treatments. CONCLUSION Changes in the arbuscular colonization percentage and oleuropein content may be connected to stress conditions provoked by a high leaf Mn concentration in the Mn_fol treatment at 90 DAT. Mn_ZA application increased leaf Mn concentration at 150 DAT compared to control and NPK treatments. It can be assumed that the dominant mechanism in Mn uptake from modified zeolite is Mn_ZA dissolution through root exudates.

Status of Fe, Mn and Zn in red beet due to fertilization and environment

Soil is a non-renewable resource, so it should be taken care of it. High quality food with sufficient yield for a growing human population can be produced only if plant nutrients are added to the soil by fertilizers to increase soil fertility, but the fertilizers have to be used economically, with the aim of raising the nutrient content available in the soil in order to meet plants’ needs. The goal of the present investigation was to determine the effect of application of organic and mineral fertilizers as well as the effect of research environment on micronutrient content in red beet root. A field trial (2003–2005) was set up in a hilly part of Croatia according to the Latin square method, with four types of fertilization (control, 50 t stable manure*ha-1, 500 and 1,000 kg NPK 5-20-30*ha-1). After digestion of plant material with concentrated HNO3, iron, manganese, and zinc were determined by an atomic absorption spectrophotometer (AAS). The highest average red beet root micronutrient contents (270 mg Fe*kg-1 in dry matter, 96 mg Zn*kg-1 in dry matter, and 53 mg Mn*kg-1 in dry matter) were determined in the first research environment (Brasljevica in 2003) with low potassium soil content. There was a general decreasing trend in contents of the studied micronutrients (Fe, Mn and Zn) with NPK 5-20-30 fertilization (and by application of high doses of potassium), certainly due to antagonistic activity with potassium. It is suggested to fertilize with both 500 kg NPK 5-20-30*ha-1 and microelement fertilizers.