Spectral reflectance and leaf internal structure changes of barley plants due to phytoextraction of zinc and cadmium

Spectral changes in the leaves of barley plant due to phytoremediation of metals—results from a pot study

“…1). This spectral change is similar to the results of Sridhar et al [2007b] who found variations in leaf NIR reflectance in barley treated with cadmium and zinc.…”

“…The probable reasons of non-significant results, as discussed in earlier sections, are: (i) relatively low concentration of Cd and Pb-spiking into soil, (ii) higher degree of tolerance of barley to Cd-and Pb-toxicity, and (iii) positive effect of NO 3 − metallic-salt. Sridhar et al [2007b] reported that Cd at 1 mM (112 mg kg ) concentration (respectively 10-and 100-times higher Cd concentration than the Cd applied in present study) had phytotoxic effect on barley and such Cd-induced stress was revealed by NDVI analysis. Arsenic and multi-metals (As 2 , As 3 , Mix 2 , and Mix 3 ) treated plants, in contrast, can statistically be distinguished from untreated plants.…”

Effect of Biosolid Amendments on the Metal and Nutrient Uptake and Spectral Characteristics of Five Vegetable Plants

“…Correspondingly, all the pepper and tomato treatments showed a significant increase (p<0.05) in plant biomass while the collard and lettuce treatments showed no significant difference in their plant biomass (Table 3) with increase in biosolid concentrations. Several studies have reported that the increase in plant metal accumulation affects the plant spectral reflectance (Kooistra et al 2004;Su et al 2007;Sridhar et al 2007a;Sridhar et al 2007b;Sridhar et al 2011) and either causes a decrease in the plant dry weight and NDVI in metal-sensitive plants. The R4.6-and R9.2-treated radish plants showed significant (p<0.05) decrease in NDVI (Fig.…”

“…All these changes in plant characteristics results in distinct light absorption and reflectance characteristics of the plants which can be used as an indicator of soil contamination and the physiological status of the plant. Several studies have demonstrated that metal and nutrient stress in plants cause changes in the spectral reflectance of the vegetation (Milton et al 1989;Kooistra et al 2004;Su et al 2007;Sridhar et al 2007a;Sridhar et al 2007b;Sridhar et al 2009;Sridhar et al 2011). In general, the plant spectral response varies with soil and plant type under study, level of soil contamination, and the sensitivity of the plant to different metal concentrations.…”

Phytoremediation to Remove Metals/Metalloids from Soils

“…Spectral refl ectance is a nonintrusive technique that has been used to monitor plant physiological status under heavy metal stress (Merzlyak et al 2003 ;Sridhar et al 2007a , b ;Su et al 2007 ). For example, spectral refl ectance around 680 nm and 550 nm can refl ect chlorophyll content in Cd-treated plants (Sridhar et al 2007b ). The spectral refl ectance in the 700-1,300 nm region is well corrected with the number of mesophyll cells in the leaves of Cr-treated P. vittata (Sridhar et al 2007a ).…”