Cultivar variations in cadmium and lead accumulation and distribution among 30 wheat (Triticum aestivum L.) cultivars

Abstract

In recent years, heavy metal pollution in agricultural soil in China has received public concern. The concept of low-accumulation cultivars (LACs) was proposed to minimize the influx of pollutants to the human food chain. Variations in Cd and Pb accumulation, distribution, and tolerance among 30 wheat (Triticum aestivum L.) cultivars were studied in a hydroponic experiment to preliminary identify LACs of Cd or Pb for further field experiments. Of the 30 wheat cultivars tested, 27 and 26 wheat cultivars showed no effect of the Cd/Pb treatments on the shoot and root biomass, respectively. The results showed that the tested wheat cultivars had considerable tolerance to Cd and Pb toxicity. Significant (p < 0.05) differences in shoot Cd concentration were observed among the tested wheat cultivars under treatments Cd1.0 and Cd1.0Pb15, ranging from 0.91 to 6.74 and from 0.87 to 5.96, with the mean of 3.83 and 2.94 mg kg(-1) DW, respectively. Significant (p < 0.05) differences in shoot Pb concentration were also observed among the tested wheat cultivars under treatments Pb15 and Cd1.0Pb15, ranging from 22.18 to 94.03 and from 18.30 to 76.88, with the mean of 50.38 and 41.20 mg kg(-1) DW, respectively. Low accumulation and internal distribution may both affect the cultivar differences in Cd and Pb accumulation in wheat shoots. Overall, wheat cultivars LF-13, LF-16, and LF-21 had lower Cd-accumulating abilities in their shoots. Wheat cultivars LF-13, LF-23, LF-26, and LF-27 showed low Pb accumulation characteristics in their shoots. An antagonistic interaction occurred between Cd and Pb in accumulation in wheat roots and shoots, which will be further studied in field experiments.

Variations in Cd and Pb Accumulations of Hot Pepper (<i>Capsicum annuum</i> L.) Cultivars for Screening Pollution- and Nitrate-Safe Cultivars

“…Liu et al [13] found that the edible parts of Lvxing 70 and Dongchu have the lowest and highest Cd accumulation properties in the 12 cabbage genotypes, respectively. Liu et al [15] have also confirmed that wheat cultivar LF-13 showed the lowest Cd and Pb accumulation characteristics in their shoots among 30 wheat cultivars. Meanwhile, vegetables are a crop that is accumulated to nitrates easily, which may be related to their nutritional properties [22].…”

“…These results indicated that hot pepper cultivars, especially the six cultivars (Nos. 1, 3, 4, 5, 7 and 9), have a higher tolerance to Cd and Pb contamination in agricultural soils compared with other crop cultivars, such as pakchoi (Brassica chinensis L.) [28], wheat (Triticum aestivum L.) [15] and tomato (Solanum lycopersicum L.) [10]. The stimulatory effect of heavy metals on plant growth may be a case of hormesis due to the physiological toxicity of heavy metals ion [29,30].…”

“…Meanwhile, the variation of shoot and root Pb concentration between high-Pb cultivar and low-Pb cultivar was similar to the phenomenon of Cd (Table 4), and there were no significant correlations (p<0.05) between the fruit Cd and Pb concentrations and the root Cd and Pb concentrations (Table 5). Therefore, the possible reason for the higher fruit Cd and Pb concentrations in high Cd and Pb cultivars is that the high (Cd and Pb) cultivars increased the ability to absorb Cd and Pb through its roots and shoots, especially the shoots being more important, which were influenced the plant genotype, the bioavailability of heavy metals, and plant metabolic pattern [15,41]. Although Xue et al [42] also found that low-Cd pakchoi (Brassica chinensis L.) cultivar 'AJKSHY' and 'BMG' had a higher Cd concentration in the roots than the high Cd cultivar 'SYM' and 'AJSZQ', no significant difference in root Cd concentrations was found among the four cultivars.…”

“…In past years, researchers found that the accumulation and distribution of HMs (including Cd and Pb) varied largely not only among crop species but also among cultivars [11,12]. Many low Cd and Pb accumulation cultivars were selected from different crops such as Chinese cabbage [12], maize [13], wheat [15], pakchoi [16], and so on. Based on these studies, the investigations of pollutionsafe crop cultivars in HM-contaminated soils have been a concern of researchers [17,18].…”

Variations of Cadmium Accumulation and Translocation in Different Pakchoi Cultivars and Screening for Cd-Pollution-Safe Cultivars Using Cluster Analysis

“…Therefore, it is imperative to find an instantaneous and effective method to reduce the potential health risks of Cd entering the human food chain through the consumption of pokchoi. Genetic differences in Cd uptake and translocation in food crops have been observed by many published papers, and the variation existed not only among cultivar species and even within the genetypes but also in cultivar parts [17][18][19]. Selecting appropriate cultivars with a high tolerance to Cd-contaminated soil and low Cd accumulation in the edible parts are reasonable to minimize soil-to-crops of Cd and reduce the risks of Cd to human and animal health.…”