Rice Plants (Oryza sativa L.) under Cd Stress in Fe Deficiency Conditions

Abstract

Due to the environment pollution by cadmium (Cd) near industrial metallurgic factories and the widespread use of phosphorus fertilizers, the problem of toxic Cd effect on plants is well discussed by many authors, but the phytotoxicity of Cd under iron (Fe) deficiency stress has not been sufficiently studied. The aim of the work was to study comprehensively the effect of Cd under Fe deficiency conditions on physiological, biochemical, and anatomical parameters of rice varieties, to identify varietal differences in plant response to the effect of double stress. Relative resistance and sensitivity to the joint effect of Cd and Fe deficiency stress rice varieties have been identified. Double stress decreased a linear growth and biomass accumulation of roots and shoots (by 36-50% and 33-46% and 32-56% and 32-48%, accordingly), content of photosynthetic pigments (Chla, Chlb, and carotenoids by 36-51%, 32-47%, and 64-78%, accordingly), and relative water content (by 18-26%). Proline content increased by 28-103% in all rice varieties, but to a lesser extent in sensitive varieties. The thickness of the lower and upper epidermis and the diameter of vascular bundles of leaves decreased by 18-50%, 46-60%, and 13-48%, accordingly. The thickness of the root endodermis and exodermis and diameter of the central cylinder mainly decreased. The thickness of the exodermis increased slightly by 7%, and the diameter of the central cylinder remained at the control level in resistant Madina variety while in sensitive Chapsari variety, these indicators decreased significantly by 50 and 45%, accordingly. Thus, the aggravation of adverse effect of Cd under Fe deficiency conditions and the varietal specificity of plants’ response to double stress were shown. It creates the need for further study of these rice varieties using Fe to identify mechanisms for reducing the toxic effect of Cd on plants as well as the study of Fe and Cd transporter genes at the molecular level.

Selection of rice breeding lines for resistance to biotic and abiotic stresses

“…Global climate change and population growth challenge plant breeders and scientists to improve the resistance of crops to ensure sustainable agricultural development and achieve zero hunger by 2030 (according to the UN) (Kim et al, 2021;Marines Marli, 2021;United Nations DESA, 2015). In this regard, research works devoted to the study of plant resistance to abiotic and biotic stresses are relevant (Akter et al, 2022;Atabayeva et al, 2022;Kissoudis et al, 2014;Zhanbyrbayev et al, 2017).…”

Effect of plant growth regulators on rice plants (Oryza sativa L.) growth under cadmium stress

“…The inhibition of chlorophyll production, chloroplast ultrastructure disruption, iron deficiency, and altered mineral nutrition all contribute to the reduced green pigment levels in leaves due to Cd. Moreover, Cd negatively impacts photosynthesis by decreasing carotenoid levels in susceptible plants [9,10].…”