Martha Bargiela

Comparison of soil tests to determine micronutrients status in Argentina soils

Abstract Soil extraction techniques to measure the status of available micronutrients for plants are important in the diagnosis of deficiency or toxicity. Mehlich 3 (M3), EDTA (pH=8.2), DTPA‐TEA, and Soltanpour and Schwab (SS) solutions were confronted for their ability to extract simultaneously copper (Cu), zinc (Zn), manganese (Mn), and iron (Fe). Argentinean soils from different taxonomic orders with widely varying properties were investigated. The values obtained showed that DTPA‐TEA and SS solutions extracted similar amounts of Zn, Fe, and Mn, while EDTA dissolved comparatively higher amounts of Fe and Mn. Mehlich 3 yielded the highest extractions for the four micronutrients. Soil pH not only affected the extraction of Mn by DTPA‐TEA, SS, and EDTA extractions, but also the extraction of Fe by EDTA. The organic carbon affected the determination of Fe and Zn in all cases. The correlations of the different tests for Cu, Zn, Mn, and Fe were significant. The results suggest that for the determination of t...

Copper and molybdenum interaction in Elytrigia elongata growing on a halomorphic soil

Abstract The experiment was carried out in a greenhouse to investigate copper (Cu) and molybdenum (Mo) interaction in Elytrigia elongata. Three rates of Mo (0,0.5, and 1 mg kg‐1) and three rates of Cu (0,5, and 10 mg kg‐1) were applied to all combinations to Elytrigia elongata grown on a halomorphic soil. The plants were cut three times, the first one 60 days after seeding, and the other two 120 and 180 days later, respectively. The results indicated that an antagonistic interaction between Cu and Mo existed in the first and in the third cut, but there was no evidence of it in the second cut. The antagonism between the two micronutrients studied was evident in the aerial part of the plant beyond a Mo concentration of 2.5±0.5 mg kg‐1, proposed as “threshold”.