Prediction of cadmium concentrations in potato tubers (Solanum tuberosum L.) by pre-plant soil and irrigation water analyses

Abstract

Potato tubers can accumulate high concentrations of cadmium (Cd) in edible portions, so that techniques to determine high risk Cd environments are required by growers. The use of combined soil and irrigation water analyses prior to crop planting was investigated as a means to predict risks of Cd accumulation in tubers. Soils and irrigation waters were analysed at 134 sites in the major potato production areas in Western Australia, South Australia, Tasmania, Victoria, and New South Wales. Irrigation waters were analysed for electrical conductivity (EC), major cations, and anions. Cadmium was extracted from soil using aqua regia (1 : 3 HNO3: HCl), EDTA (ethylenediamine-N,N,N′,N′-tetraacetate), DTPA (diethylene-triamine-pentaacetate), 0·01 M CaCl2, 0·01 M Ca(NO3)2, 0·1 M CaCl2, and 1·0 M NH4NO3. The preferred test procedure was validated in a subsequent sampling and analysis program at 39 sites. Irrigation water quality (EC or Cl concentration), measured prior to planting, explained the greatest variation in tuber Cd concentrations. Of the soil test procedures, only Cd extracted by 0·01 M CaCl2 significantly improved the predictive capacity of water EC. These 2 measures explained >55% of the variance in tuber Cd concentrations. The data set were transformed to generate a probability curve for exceeding Cd concentrations of either 0·05 or 0·1 mg/kg fresh weight, the latter being the current maximum permitted concentration (MPC) in Australia for potato tubers. The probability of producing potato tubers exceeding 0·05 and 0·1 mg/kg fresh weight was >50% once irrigation water EC increased above 1·4 and 3·0 dS/m, respectively. Using the relationships developed, growers should be able to quantify Cd risks by a simple test of irrigation water EC prior to planting and, if further precision is needed, also determine CaCl2-extractable Cd in soil.

Cadmium concentrations in some New Zealand wheat grain

“…On average the greatest concentrations of Cd were extracted using 0.04M EDTA, whereas the lowest were extracted using \M NH 4 NO 3 . This type of relationship for Cd extraction from soil has been previously reported by other researchers (e.g., Gray et al 1999a;McLaughlin et al 1999) where chelating agents extract higher amounts of metals compared to dilute neutral salts such as NH4NO3.…”

Effect of soil pH on cadmium phytoavailability in some New Zealand soils

“…It indicates that CaCl2, NH4NO3, Ca(NO 3 ) 2 , and NH 4 C1 were sensitive to soil pH and in general supernatant pHs were within 0.3-0.5 pH units of the soil water pH. This type of relationship for pH and NH4NO3 has been previously reported by He & Singh (1994), Guttormsen et al (1995), andMcLaughlin et al (1999) and for CaCl 2 by Sauerbeck & Styperek (1985), Jackson & Alloway (1991), and Whitten & Ritchie (1991). EDTA on the other hand, although adjusted to pH 6.0 is not buffered and reflected the soil pH, however not to the same extent as NH4NO3 and CaCl2 .…”

Transfer Function for Phytoavailable Heavy Metals in Contaminated Agricultural Soils: The Case of The Korean Agricultural Soils Affected by The Abandoned Mining Sites

“…42(pore size 2.5 ㎛) 여과지로 여과하고 ICP-OES(8300DV, Perkin-Elmer, USA)로 분석하였다. 점토함량은 마이크로 피펫법 (Miller and Miller, 1987) (Bingham et al, 1984;McLaughlin et al, 1999)을 변형시킨 추출법으로서 CaCl2 의 염소이온이 양이온 치환력 이상으로 카드뮴 이온을 추출 하는 단점을 보완하였다 (Seo et al, 2013 (Naidu et al, 1994;Sauvé et al, 2000aSauvé et al, , 2000bKrishnamurti and Naidu, 2003). Table 2.…”